TONS of questions regarding Turbo Timer, Idling, Boost, and my weird FD!
 

Hey Folks,
I feel stupid posting yet another Thread, but since I'm clueless..

Here it comes:
My FD has dual oil coolers running parallel as far as I can tell, and - used from the '89 supra turbo I had - I always cool down the car when i was crusing, meaning I take a route with quite a long slight downhill stretch over ~2 Miles, rolling in fifth gear with ~ 70 km/h / 40 mph , barely touching the gas, and from there on 100 meters to my house.

The car is equipped with an oil temp gauge, after the mentioned downhill stretch, oil temps go down to around 70-80°C -> 158 - 176°F.
When idling, for example at a drive thru, i recognized the oil temps go up to like 105°C / 220°F, and drop rapidly to ~ 90°C / 195°F when driving again.

Now. Should I let the turbo timer do its thing at all? It's pointless, no?
Having a "Border Burnout" catback without any silencer (yikes!!), i'm sure my neighbours would really appreciate if I just STFU with my "weird right hand drive loud bat mobile" right after arrival.

Also, regarding this, i noticed a weird idling behavior of this car.
When its cold it idles at around 1500 rpm. Previous owner says thats coming from a mild streetport the car probably has. (Can't confirm this at this point)
Here's the weird thing: Occasionally it idles smoothly at something like 750-800 rpm.

Generally i have to say it idles weird. Sometimes very low and a bit on the rough side for 1-2 seconds, sometimes at 1500 rpm, sometimes at 800, sometimes at 1100, but not at a stable rpm whatsoever, and i can't really determine what makes it idle in a certain way. Today it was idling kinda high at 1100-1200 after driving for like 20 minutes, then i had to shutdown the car for another 20 minutes, and it was idling super nice at 800 rpm when i restarted it. Does it make a Difference if I put it in 1st gear when starting? Or if i push the gas pedal down before starting it? I read something about this somewhere some years ago. So i tried a few things, but i think this might only points towards AT cars? I'm confused. :ponder:

When the idle is rather high, it also makes some random popping sounds, sounding and feeling like misfire, you can really feel it! like "brabrabrabraPOPbrabrabrabrabrabrabraPOPbrabrabrabr a.." is that normal / usual for a probably in Japan ported engine? Can't tell if the physically noticable slight shocks are coming from the insane exhaust or if its the engine shaking the car. I think its both. Should I be worried? I don't think its something super drastic, since the car doesn't smoke air or oil at all and it starts RIGHT up, i crank the starter 1 second at max and it starts hot or cold ALWAYS. Which I think is impressive for a modded ~50500 mile FD. Thinking about changing the spark plugs but the previous owner said that it makes no difference in that regard..

I think the car may have some sort of vaccum or electrical problem somewhere as there are a few more little strange things. I'm sure the Boost is turned up quite a bit (I think I saw it peaking at .85 BAR which is roughly 12PSI) and.. its FAST like.. really really fast, not to compare with a 235HP supra at all, feels more like 300HP! 3rd gear Wheelspin at 65 mph WOT on 255/40/R17 tires on a slightly moist road! IS THAT NORMAL?? Also I noticed two holes in the interior, indicating there might have been a PowerFC Commander installed. But the previous owner states that it's running on the stock ECU, which makes this even more confusing for me. Didn't take a look at the ECU yet. But i will! Maybe it has a PowerFC running!

But here's the thing that troubles me the most: I think it runs into Boost and or Fuelcut! Again, occasionally! Sometimes I can push it really hard repeatedly, 2nd-4th gear, no problem, but sometimes the boost comes on hard and ZANG no power with the Blowoff working for a fraction of a second, followed by full power again - but only once! Then it keeps pulling. I might should try to record this.

Well, while driving, the weird thing is: The 2nd Turbo kicks in really hard, and at the point where the boost transitions from Turbo 1 to Turbo 2 the BOV opens for just a tiny moment, and the car has a noticable power loss. But then BAAANNNG it kicks you in the back of your head like nothing i ever felt, thats for sure, and it keeps pulling way up to where my senses tell me to shift - haven't heard the beep yet and I'm not looking forward to ever hear it! 6500 is enough for the start, of a RHD starter I think!

Anyway, I'm looking forward to get it to a dyno soon to get an idea what's up, but theres nobody in my area with rotary knowledge.

You see guys, I'm struggling to categorize this whole car and its behavior. Please help!

Any inputs as always highly appreciated since I still have no clue.
Thank you and have a nice day!

//Edit:
I think this idle popping might come from the mods that were done to the car. gonna capture it anyway!

Is the turbo timer useless? Probably. You can achieve the same results by driving your car conservatively for a few minutes before you park it. The 1500rpm idle while cold is normal until it reaches operating temp. Not 100% sure on FDs, but in an FC you can stop this by putting the car in gear while starting, then put into neutral. Should idle in spec after that. If the car is hunting for an idle, it could be anything from a vac leak, to fuel issue, to TPS out of spec. You say you might think the boost is turned up...Have you checked for a boost controller Wastegates improperly sized for an aftermarket turbo? The random popping sounds are fairly typical, especially if its been modified with an exhaust, port, tune, etc. Until you open the engine up to examine port size or determine if you're running an aftermarket ECU, it's really hard to tell the source of some of these symptoms. Some could be related while others could be separate issues. You might try to focus on solving one problem at a time. Check which parts are OEM and which are aftermarket and examine those systems first. Hope this helps some!

The boost gauge sometimes hits up to like .84 - .86 bar as far as i can tell, which is roughly 12-12.5 PSI, so i really guess its boostcutting - the warning LED on the boost gauge also turns on when going WOT.
I really think i should get a PowerFC with a Commander, a Wideband (is there any plug&play wideband which will work with the factory ECU and the PFC when i get one?) and some idea of how the boost was upped.
Because that car is really fast. And it chugs gas gallonwise holy damn, even my old supra turbo was economic in comparsion!

I also read a bit the vacuum, its pulling 55mmHg in idle (1450~ rpm) and around 60-65 mmHg at around 2500 rpm. Is that in spec or do i need to find leaks?

Also, generally, what is considered boost when warming up the engine? I try to stay way into vacuum (~20 - ~30 mmHg) on the boost gauge, but would it be ok to go to like almost 0mmHg? Like, is it ok if the turbos spool up a bit but not actually boost? Because driving like that is even slower than driving my NA when its cold..

As far as i can tell on the turbos, its the twin turbo sequential setup:
I got a pretty loud but cute sounding turbo which comes online as soon as I give it a little gas, no matter what rpm really.
then at around 4500 there comes another, slightly quieter but more agressive and sharp sounding turbo, online and pushing pretty hard.
IDK if these are the same you guys are running since it's a '96 model, but as far as I know the turbos were upgraded in the '99 spec models.

So this is what the engine bay looks like, i can't see a boost controller.
it has an aftermarket FMIC and water cooler, hardpiping, some sort of greddy blowoff valve which just sounds perfect, not like some squeezed bird or something, some HKS intake i think.
where are spots where a boost controller is usually placed?
You might see that open thing there right besides the coolant filler neck - what is that? the previous owner is hellishly clueless or doesn't want to tell me. Should I put some sort of Air Filter on it? What is it anyway?

https://cimg0.ibsrv.net/gimg/www.rx7...497da7ad3c.jpg

Cats are stock and it has a hellishly loud Border Burnout catback which I am willing to exchange for something silent asap - even a stock muffler i'd take happily!
BTW is it true that I'll roast my engine when going with the stock exhaust because it's too restrictive? Considering the car *might* have a mild streetport?

The boost gauge sometimes hits up to like .84 - .86 bar as far as i can tell, which is roughly 12-12.5 PSI, so i really guess its boostcutting - the warning LED on the boost gauge also turns on when going WOT.

that boost level is fine. its a little bit high but not something to worry about. the warning on the gauge is set to go off at whatever boost level it was set at. you can change it so that it doesnt do that.


I really think i should get a PowerFC with a Commander, a Wideband (is there any plug&play wideband which will work with the factory ECU and the PFC when i get one?) and some idea of how the boost was upped.
Because that car is really fast. And it chugs gas gallonwise holy damn, even my old supra turbo was economic in comparsion!

you definitely should get a power fc and wideband and get a proper tune. no wideband is plug and play with a stock ecu unless the car is set up to have it from the factory. wiring in the wideband to read on the power fc doesnt give it any power to do anything with the reading other than display it. the user still has to make the adjustments. even when enabled, i think it will only read the narrowband range anyway. the fuel consumption may be a tiny bit excessive since its untuned with all the mods it has on a stock ecu. with a power fc, all of that can be tuned to be better.

I also read a bit the vacuum, its pulling 55mmHg in idle (1450~ rpm) and around 60-65 mmHg at around 2500 rpm. Is that in spec or do i need to find leaks?

your idle shouldnt be that high. something is wrong. your vacuum reading at that rpm is kind of pointless as a good measure should be taken at idle speeds. 800-1000rpm. definitely go looking for leaks.

Also, generally, what is considered boost when warming up the engine? I try to stay way into vacuum (~20 - ~30 mmHg) on the boost gauge, but would it be ok to go to like almost 0mmHg? Like, is it ok if the turbos spool up a bit but not actually boost? Because driving like that is even slower than driving my NA when its cold..

boost is anything above 0. stay below it when the car is cold. drive however you like, just stay below 0.

As far as i can tell on the turbos, its the twin turbo sequential setup:
I got a pretty loud but cute sounding turbo which comes online as soon as I give it a little gas, no matter what rpm really.
then at around 4500 there comes another, slightly quieter but more agressive and sharp sounding turbo, online and pushing pretty hard.
IDK if these are the same you guys are running since it's a '96 model, but as far as I know the turbos were upgraded in the '99 spec models.

if thats how it runs then you are still sequential. you can verify what twins you have by either looking for a stamp on the compressor housing that says n3a1, n3c1 or n3g1. you want to see n3g1. those are the 99s. you can also take off your front intake and look into the compressor housing. if the housing has a black ring around the wheel then they are 99.

So this is what the engine bay looks like, i can't see a boost controller.
it has an aftermarket FMIC and water cooler, hardpiping, some sort of greddy blowoff valve which just sounds perfect, not like some squeezed bird or something, some HKS intake i think.
where are spots where a boost controller is usually placed?
You might see that open thing there right besides the coolant filler neck - what is that? the previous owner is hellishly clueless or doesn't want to tell me. Should I put some sort of Air Filter on it? What is it anyway?

the engine bay looks good. really nice and neat. any installed boost controller will be evident by the solenoids placement somewhere in the front of the turbos bridging the vacuum lines on the actuators. if its a manual controller then it will be thing with a knob on it and if its electric then it will be a solenoid with a plug coming out of it. also with the electric, there will be some sort of controller in the cabin. the open thing beside the filler neck is the air pump. you can put a filter over the end if you want but it doesnt matter. its purpose is to dilute your exhaust. its for emissions. it sucks in fresh air and pumps it into your cat.

Cats are stock and it has a hellishly loud Border Burnout catback which I am willing to exchange for something silent asap - even a stock muffler i'd take happily!
BTW is it true that I'll roast my engine when going with the stock exhaust because it's too restrictive? Considering the car *might* have a mild streetport?

no. with no power fc and the mods you have, that stock cat is probably the only thing SAVING your engine right now. once you open up that exhaust on the stock ecu, boost tends to do what it wants. theres only so much the stock ecu can do.

i love how many questions you have and that youre trying to educate yourself instead of being ignorant. keep browsing the 3rd gen section. theres A LOT of information here that im sure you can use.

My FD has dual oil coolers running parallel as far as I can tell, and - used from the '89 supra turbo I had - I always cool down the car when i was crusing, meaning I take a route with quite a long slight downhill stretch over ~2 Miles, rolling in fifth gear with ~ 70 km/h / 40 mph , barely touching the gas, and from there on 100 meters to my house. The car is equipped with an oil temp gauge, after the mentioned downhill stretch, oil temps go down to around 70-80°C -> 158 - 176°F.
When idling, for example at a drive thru, i recognized the oil temps go up to like 105°C / 220°F, and drop rapidly to ~ 90°C / 195°F when driving again.
Now. Should I let the turbo timer do its thing at all? It's pointless, no?

turbo timers are useless in general. your cool down lap sounds like plenty of time to get everything to normal temps. you really only should do stuff like that if you were getting on it and making fun time with compressed air. not like 1 or 2 pulls but some prolonged high rpm time. the way your temps act is normal but 220 at a stand still sounds kind of high. i dont know what the stock thermostat is set to open at but 220 sounds high. does it ever go higher than that? do your temps suddenly drop when sitting at a standstill?


Also, regarding this, i noticed a weird idling behavior of this car.
When its cold it idles at around 1500 rpm. Previous owner says thats coming from a mild streetport the car probably has. (Can't confirm this at this point)
Here's the weird thing: Occasionally it idles smoothly at something like 750-800 rpm.

definitely a vacuum leak of some kind or one of the many idle controls are sticking. no "mild street port" needs to idle at 1500. thats crazy high. that shouldnt be hard to troubleshoot.

Does it make a Difference if I put it in 1st gear when starting? Or if i push the gas pedal down before starting it? I read something about this somewhere some years ago. So i tried a few things, but i think this might only points towards AT cars?

no, doesnt make a difference.

When the idle is rather high, it also makes some random popping sounds, sounding and feeling like misfire, you can really feel it! like "brabrabrabraPOPbrabrabrabrabrabrabraPOPbrabrabrab ra.." is that normal / usual for a probably in Japan ported engine? Can't tell if the physically noticable slight shocks are coming from the insane exhaust or if its the engine shaking the car. I think its both. Should I be worried? I don't think its something super drastic, since the car doesn't smoke air or oil at all and it starts RIGHT up, i crank the starter 1 second at max and it starts hot or cold ALWAYS. Which I think is impressive for a modded ~50500 mile FD. Thinking about changing the spark plugs but the previous owner said that it makes no difference in that regard.

is it something like this? if so, changing the plugs will help with it but its a tuning issue. a power fc will fix that.

I think the car may have some sort of vaccum or electrical problem somewhere as there are a few more little strange things. I'm sure the Boost is turned up quite a bit (I think I saw it peaking at .85 BAR which is roughly 12PSI) and.. its FAST like.. really really fast, not to compare with a 235HP supra at all, feels more like 300HP! 3rd gear Wheelspin at 65 mph WOT on 255/40/R17 tires on a slightly moist road! IS THAT NORMAL?? Also I noticed two holes in the interior, indicating there might have been a PowerFC Commander installed. But the previous owner states that it's running on the stock ECU, which makes this even more confusing for me. Didn't take a look at the ECU yet. But i will! Maybe it has a PowerFC running!

spinning in 3rd on a 255 that has grip isnt exactly normal for stockish power levels lol. good for you if you can though. holes in the interior dont really indicate the installation of a power fc. pull the passenger kick panel off and see what ecu you have. youll know right away which one. if/when you go power fc, youll need a datalogit as well so you can make adjustments.

But here's the thing that troubles me the most: I think it runs into Boost and or Fuelcut! Again, occasionally! Sometimes I can push it really hard repeatedly, 2nd-4th gear, no problem, but sometimes the boost comes on hard and ZANG no power with the Blowoff working for a fraction of a second, followed by full power again - but only once! Then it keeps pulling. I might should try to record this.

yeaaaaaaa........ stop doing that lol. it may happen one time and that will be the last time it happens if you know what i mean. although occasionally, dont walk into a situation where its possible for that to occur.

Well, while driving, the weird thing is: The 2nd Turbo kicks in really hard, and at the point where the boost transitions from Turbo 1 to Turbo 2 the BOV opens for just a tiny moment, and the car has a noticable power loss. But then BAAANNNG it kicks you in the back of your head like nothing i ever felt, thats for sure, and it keeps pulling way up to where my senses tell me to shift - haven't heard the beep yet and I'm not looking forward to ever hear it! 6500 is enough for the start, of a RHD starter I think!

yea, thats about normal for the transition. well, not normal as its supposed to be smooth but normal in the sense thats how it typically feels. you have an issue with something though, the transition shouldnt be THAT abrupt

So much unformation, lovely, I'm super happy right now. THANK YOU !
I think I'm gonna take a closer look at things now and trying to find out how to find my vacuum leak, since I'm sure the car has one or more somewhere. Hell, I might even get 20 meters silicone hose and just replace everything for good.
For the next startup I'm gonna take a Video and post it here, and I'm gonna do another Clip with my Idle sound stuff.

Again, thank you so much, I'll keep this one updated!

So I've made some short clips regarding these topics, gonna upload them tomorrow i think.

I also taken my time to process your input:

no. with no power fc and the mods you have, that stock cat is probably the only thing SAVING your engine right now. once you open up that exhaust on the stock ecu, boost tends to do what it wants. theres only so much the stock ecu can do.

Would it be smart then to insert a silencer into my Cannon? -> https://www.japspeed.com/media/image...609B-INS01.jpg

the way your temps act is normal but 220 at a stand still sounds kind of high. i dont know what the stock thermostat is set to open at but 220 sounds high. does it ever go higher than that? do your temps suddenly drop when sitting at a standstill?

Oil temp, not water temp here! my car is equipped with a water temp gauge but i think its broken, doesnt do anything but blink red when its connected. so i disconnected it. you'll see in my video clips.
The thermostat is set to open at 82°C-ish regions, maybe 80°C, maybe 85°C, don't really recall what the previous owner said.

spinning in 3rd on a 255 that has grip isnt exactly normal for stockish power levels lol

might be the clutch aswell, looks like it's gonna be a pain in the butt to do this.. but then again, maybe i'll just do the friction plate. this got me thinking though how bad the car might have been treated in its previous life.... it's an FD dammit, not some throw away clutch kick junker! :crying:

yeaaaaaaa........ stop doing that lol. it may happen one time and that will be the last time it happens if you know what i mean. although occasionally, dont walk into a situation where its possible for that to occur.

alright, that means no more WOT for me, because there is nothing special to do to make it happen, except flooring it. I think for some reason the car cant hold a steady boost level, can this result from the catback that's installed? and also, could a silencer help here with a tad more back pressure in the exhaust system? well i'm gona pamper it for now.

yea, thats about normal for the transition. well, not normal as its supposed to be smooth but normal in the sense thats how it typically feels. you have an issue with something though, the transition shouldnt be THAT abrupt

alright okay, well, i think the thing is, it's only feeling to be hitting really hard when the damn boost gets to high just as soon as the secondary turbine kicks in. 1st turbine going max boost -> 2nd coming online -> too much boost / boostcut -> sudden full power from 2nd turbine. does that make sense?

anyhow i'm now editing my footage and let it upload overnight (yay 200kb/s HSPA right now!!)
Oh and i feel like my car drinks 10L 98Octane for 25km. That would make 40L / 100km. 6mpg?? I think i should fill it up, drive 100km, fill it up again and see what it takes. That fuel gauge is weird anyway. Just as my Oil pressure gauge which randomly drops to 0 and back up to 4 bar. Guess its come faulty cable and a misalignment.:drool1: what a funny car, seriously.

Edit: Lets see if I can get a yt video in here too

Would it be smart then to insert a silencer into my Cannon? -> https://www.japspeed.com/media/image...609B-INS01.jpg

you can. it will only further restrict your exhaust flow.

Oil temp, not water temp here! my car is equipped with a water temp gauge but i think its broken, doesnt do anything but blink red when its connected. so i disconnected it. you'll see in my video clips.
The thermostat is set to open at 82°C-ish regions, maybe 80°C, maybe 85°C, don't really recall what the previous owner said.

yes, i am talking about oil temps. the stock oil coolers have a thermostat as well. its built into the cooler.

Oh and i feel like my car drinks 10L 98Octane for 25km. That would make 40L / 100km. 6mpg?? I think i should fill it up, drive 100km, fill it up again and see what it takes. That fuel gauge is weird anyway. Just as my Oil pressure gauge which randomly drops to 0 and back up to 4 bar.

dont mind the oil pressure gauge. its inaccurate and unreliable. what youre seeing is normal. your gas mileage is miserable but about right for your set up with no tune on a stock ecu.

Thanks again for your Answers.

I have actually no idea when the oil thermostats open. It's really cold over here (2-6°C when i get to work and back..) and when really cooling off the car, the oil temps drop in a manner of a few minutes down to 60°C, never really getting hotter than 85-90°C (that damn gauge isnt lit in any way..). Cooling wise this car seems to be monstrous and actually done in a considerable manner. But on the other hand it doesnt seem to be balanced very good - its getting cold very fast.

I Probably should get a PowerFC - luckily the yen is super weak right now, thinking of getting one from japan but i guess there's noone in germany able to tune it properly for a reasonable price so besides becoming a bit of a rotaryhead, i'd also have to educate myself in ECU programming. that doesnt sound too easy at all. also not sure if i should get one when i dont know where this car is going and what problems might have higher priority soon. For example my vaccum issue. Which i got updates for!

When i coast (i hope that's really what i mean) and roll towards a traffic light, lets say in 2nd gear, and push down the clutch at ~2000 rpm, the car will stay there for a while and then drop to its ******** 1400-1500 idle rpm. But it really feels like there's something stuck.
I was already looking for those kind of one way vaccum hose valves (sorry for my english, please dont hate me) but i couldnt find them. I think maybe the throttle cable and/or one or more of these things might be stuck or just acting kind of sluggish.

Are there any diagrams or pictures of where i can find these things? Its not that i'm lazy, but i have no idea what to search for on the forums when it comes to my '96 FD stuff.

My head is about to explode because I'm learning so much about that car..

But I'd really like you to take a look at my video.

At 3:45 that open thing there is the air pump i guess?
At 4:11 you can see some device with a vaccum line under the secondary intake pipe with an open end, what is that? Is that supposed to be open like that? Is it the BOV from the 2nd turbine?
At 5:16 you can see some open hose on the right side from the secondary intake pipe, do you have a clue what it does, what it is? After fearing of getting my finger sucked in and chopped off from going near the supposed air pump, i wasn't particularly interested in sticking my finger into holes i dont know what lurks in it.

NOW, should I do something about that open stuff, will it improve anything if i seal these off?

Is there anything particularly weird going on in the engine bay you might point out to take a closer look at?

YOU are my HERO by the way mister rex!

At 3:45 that open thing there is the air pump i guess?

Yep, that's the air pump. You can get cheap mini filters for it, something along these lines: TKT Breather Filter RX7 but i believe there are many other options out there.


At 4:11 you can see some device with a vaccum line under the secondary intake pipe with an open end, what is that? Is that supposed to be open like that? Is it the BOV from the 2nd turbine?

It's the charge relief valve - it is fine to vent to atmosphere but would be quieter if a filter is added also.


At 5:16 you can see some open hose on the right side from the secondary intake pipe, do you have a clue what it does, what it is? After fearing of getting my finger sucked in and chopped off from going near the supposed air pump, i wasn't particularly interested in sticking my finger into holes i dont know what lurks in it.

You stuck you finger in the air pump intake. As for the other open hose....no idea where that goes - anyone?!?


NOW, should I do something about that open stuff, will it improve anything if i seal these off?

Personally for the sake of a nice clean engine bay I would. In the short term you can add mini filters as suggested, or my preference would be to grab some Apexi or HKS or FEED intakes that support all the hoses actually being plumbed where that are supposed to be as per factory. In the long run I would then focus on getting that Power FC and then removing the air pump and cats with a supporting engine tune.


YOU are my HERO by the way mister rex!

Agreed, nice to see the community continuing to support one another! :icon_tup:

Hey Guys!

So here is my little, quite depressing update:

The car chugs about 21L/100km which is roughly 11MPG - no boost! Thats terrible!
I need to improve this fast, even before getting another ECU.

Here's my plan so far:
1. get engine error codes
2. probably replace O2 sensor << a 4 pole Bosch will do for this car, right?
3. check for vacuum Leaks. << for this i really need tips on how to do it properly, and a vac line diagram for a '96 JDM FD. I've seen a coloured one here but i can't find it!
4. check vac valves - again, i need to know where they are
So Far, i found THIS:
https://cimg8.ibsrv.net/gimg/www.rx7...4fa5c57d90.jpg
What is it, what does it do? :blush:
It's on the Backside of the Intake Manifold near the Throttle Body.
I think its clogged aswell. Clean or replace?
And where does this Hose go? i presume to replace it the entire runners have to come off along quite a lot of more stuff. right? :molepoke:

Are there any more things I can do at this point to improve the cars fuel consumption? Anything to check? ANY INPUT IS HIGHLY APPRECIATED since I'm getting the creeps!

Going decat and no air pump is no option in germany if you want to keep driving the car. California emission laws are a joke compared to german emission laws. Anything except stock values -> not allowed. Simple as that. :D

Gotta go, I'll keep the Updates coming and thank you all again greatly for your input.
Guys swing by to germany, I'll be cooking and serve a nice beer for you!

EDIT:
GREAT SUCCESS! :crackup:
I found out what it is and i'm gonna cap off the hose tomorrow and see what my idle does.
If it works I'm super happy, but i'm gonna replace it anyway since its a protective feature of the car.
Do i see this right that this damn vac line goes one time around the entire engine? or just around the intake? It looks like i have to pull the damn engine to replace it!

So another little Update.

I just sealed off that hose for now and it definately improved the cars behaviour-

I think I have improved vacuum now, the car is going WAY better on the fuel, driven 70km today with quite some boost here and there, and the fuel needle barely even moved, though i was pushing it. At some point i thought it was broken! So, success here. Update at the next 100km for a consumption check.

BUT
The crappy idle stays where it was and also when i revved it a bit and want the rpms to drop, they'll settle around 2000 rpm and then slowly drop to 1450~. Which is still too high.
With this "idle" the car now pulls a strong 65mmHG vacuum all the way to 3000 rpm in neutral. Since I do one ways the last couple of days, i didnt get it to idle at its 700-800 rpm (restarted warm)

I checked the throttle cable and it has a bit of sag in it, gonne re check tomorrow with someone pushing it down and releasing it so see if it might be a bit sticky and returning slowly.

Next steps? I guess still checking error codes by soldering a little diagnose LED device and getting a multimeter to maybe check the TPS.
Any other Ideas of what i could try?

Thanks guys!

Is it possible that the above shown, broken actuator (is it one?) might be stuck, holding up the dual throttles just a tad?