FrankV702

iTrader: (14)

Hey what's up guys.. I'm a new FD owner, I was previously always an fc guy. I'm not sure if this should be here or the power fc section.

Anyways, my car is a 92 RHD FD. The car has a 3" down pipe, stock cat, apexi n1 exhaust, upgraded hks intercooler piping for the stock intercooler, and knightspors ebs III boost controller. I have inhave the boost controller in mode one which I believe is just a boost gauge mode. It had a a knightsports tuned factory ecu when I bought it and it ran good but had a super rich idle. I recently bought some upgrades for it and want to start modifying it a little bit. Compression is 106-108 on all sides both rotors and it's pulling about 18"-19" of vacuum at idle 950rpm idle.

I bought an AEM boost gauge, AEM x series wideband and a power FC that I installed. Last week on Tuesday. The install of the power fc was super easy compared to what I was used to with an fc and buildings a harness for a haltech.

So when I installed the power fc last week, the weather was a lot cooler than it is now. Not sure how it got so warm so quick but it is Vegas so it's inevitable. I installed the power fc in the evening when the sun was down, I followed the instructions in the manual and the dale Clark guide. It started up fine, idled fine, drove fine, and boosted fine. Today was the first day I drove it from last week and it was drivingdifferently. It starts up fine and idles fine but when I drive, only in either first or second gear, after I drive and push the clutch in, it stalls out. ONLY when it's in first or second gear and I push and hold the clutch in. When I let the clutch out, it kick starts back on but stays at about a 2k idle for a few seconds then hunts around for a few moments and drops back down to normal. Also, the boost is only going up to a max of .55 bar. Last week it was boosting at .67 bar and felt significantly faster. Afrs at WOT with the power FC are at 11.0-11.3. With the knightsports ecu, afrs at WOT we're 10.0-10.5.

I re-initialized the power fc so I'm running the stock power fc base map and it is the newer version of the power fc with the OLED commander. Does it sound like my car may just need a tune? Did the weather affect it? You think it's just trying to still "learn" how to drive? Boost leak maybe?

One of my spark plug wires is a little loose on the rear trailing plug and will come off with a slight nudge. I got some new plugs and wires coming this week so I'll swap them out this weekend.

I'm going to put the stock ecu back on tonight and see if it does it with the stock ecu. It ran like a champ with the stock ecu though just super rich.

Thanks for any input!

arghx

iTrader: (3)

see this thread on the common problems after power FC install https://www.rx7club.com/3rd-generati...needed-841706/

IRPerformance

iTrader: (41)

Raise the deceleration fuel cut settings by 50-100 rpm each. That should help. Really you should get a professional tune. The base map is fine to get the car running and moving around but it leaves a lot to be desired in safety and full potential.

FrankV702

iTrader: (14)

I really do need to get it tuned. I'm going to have to just suck it up and tow it down to Ca in the next few weeks to have someone to tune it for me. There's no way to remote tune it, is there??

So a couple of updates, I disconnected the air pump last night, re-initialized the pfc, and for the time being it's not Giving me that stalling issue in first and second gear.

The boost issue was there still so this morning I took off the boost controller. Who ever installed it put it on some type of patch harness between the factory harness and ecu so I just unplugged that whole thing and plugged the factory connectors into the ecu. I brought it to work today and it boosted fine. It hit a peak boost of 10.7psi. AFRs still stood in the low 11s, so that's good. On the ecu harness, there's 4 total pins that are jumpered together. I'm going to need to find an ecu pin layout to find out what they are and why they're jumpered.

This weekend I'm going to do general maintenance, change plugs, wires, & oil. Last night when I was looking at my spark plug wires, the rear trailing plug wire is super corroded inside the boot. I ordered a block off plate kit, an idler pulley and new belt so I'm going to attempt to do the simplified sequential modification. I know my way around an fc engine bay pretty well but the rats nest on an FD looks like a whole new beast! Almost makes me want to go Single turbo just to get rid of all of that.

Arghx, thanks for the link! That thread has a whole lot of super useful info for people like me! Thanks for sharing so much info on there!

arghx

iTrader: (3)

There are resources for DIY tuning if you want to go that route. PM sent.

Could be boost creep if the boost controller isn't running at all and it's at spring pressure. FD creeps just like the FC does if you open up the exhaust enough. Either port the wastegate or put restriction back in (restriction plate or cat). You will never get it to control boost right if you let it creep.

You can control the boost for primary and secondary turbo independently with the Power FC and a couple 3 port solenoids, should be less than $100.

https://www.rx7club.com/3rd-generati...tegies-874031/

https://www.rx7club.com/3rd-generati...lenoid-531676/

You can replace the check valves and 4 main stock solenoids related to sequential turbos (the ones that control the switching between the two) for about $200 with brand new OEM parts, if you want to go that route (that's what I did). Just call Ray Crowe for OEM solenoids and Dale Clark for aftermarket viton check valves.

94 Wiring diagrams page Z-36 has the pinout, as well as the F section of the service manual, available here Foxed.ca - Mazda RX-7 Manuals

Are you sure they're jumpered by somebody tampering with it or are these just grounds tied together? You need to rewire the fuel pump. The stock fuel pump actually flows pretty well, and by most reports is enough for stock turbos, it just needs to be rewired for more voltage (same idea as a rewire on an FC T2). When you rewire the pump it throws off the tune, so you need to rewire and then tune it.

It's just like an FC, you need to decide whether you want to keep the thermowax and idle air control valve (BAC valve/ISC valve/whatever). If you don't like giving the car gas pedal every time it starts, or idling high, or whatever, you don't want to delete the throttlebody coolant hose or block off the idle speed valve. I'm also assuming you plan to delete the air conditioning, because you're making your life difficult if you delete the ISC valve.


You're welcome to a fellow FD owner who has a background in FC's

FrankV702

iTrader: (14)

So I drove my car on lunch and it was stalling again only in 1st and 2nd at low speed with the clutch in. I noticed my injector duty cycle was dropping to 0 and then would raise but the RPMs were super low and the car would stall before it could catch back upI did what IRPerfomance said and raised the deceleration fuel cut settings by 50 RPMs and it's fine now.

It's having a boost issue in 1st gear. Still only getting about 7 psi in first gear. Second gear it's getting to a max of 10.7psi and feels noticeaby different. It feels like the second turbo isn't kicking on in first. I was reading somewhere that if the first turbo doesn't get to 8psi, the second turbo won't kick on. Is there any truth to that?

It's not the ECU as I swapped in the knightsports ecu and it's still doing the same thing. I'm thinking possibly the solenoids? I did get some break cleaner and sprayed it in a few spots and got no raise of idle. It's not idling or anything like it has a vacuum leak or anything.

Thanks for the pages to look for the ecu pinout Arghx! Now that I'm thinking about it, one of them may be grounds tied together but the other one is definitely jumpered by someone tampering with it as it's got those autozone wire splicers on the wire about 4" above the ecu plugs.

I do want to keep the AC as it's ice cold and temps in Vegas stay around 100 or above in the summer, even at night. I'm going to leave the ISC valve.. I plan on using the ACV block off plates, OMP block off plate, and the AWS block off plates. The guys that did a emissions inspection on my car at the DMV swore it had an EGR valve. I haven't really looked if it does but my understanding is it doesn't since it's a JDM car. If it does, I'll use that block off plate too.

I have to look more into the split air tube, and rear oil return block off plates to see if I need/can use those.


I do want to put new solenoids for the sequential system on there so I'll have to message Ray Crowe and Dale Clark for the parts needed. Thanks for the info!

arghx

iTrader: (3)

you need to overhaul the sequential system when you do the vac job. Maybe you have a bad check valve. Maybe you are missing the restricter pill for the precontrol valve (which controls boost on the primary turbo).

Either go non sequential or IMO replace all the solenoids and check valve with new parts, along with the vacuum hose. Personally I don't recommend non sequential. Honestly even with working sequential twins the car doesn't make that great of low end torque when you are used to modern turbo piston engines that hit full boost at 2000rpm in top gear. With non sequential it's even worse.

Your emission inspection guys probably thought the ACV was an EGR valve.

Question: If you need to pass emissions, why are you ditching the air pump?

FrankV702

iTrader: (14)

I'm going to contact the resources above to get the solenoids and viton check valves to redo the sequential system. Ideally, I'd like to upgrade to BNr stage 3 twins in the future so keeping them sequential is a priority for me. I bought 20ft of 3.5mm silicone hose and 8ft of 6mm silicone hose from boostcontroller.com yesterday. I'll get there.

The emissions inspection was just a one time thing because the car was imported. I don't need to do an annual inspection or pass smog as the car is 25 years old so it's not needed here.

arghx

iTrader: (3)

the solenoids you need are:

Mazda part # 1480-13-240A - 2 of these total. One is for Charge control and one is charge relief solenoid.

Charge control switches the butterfly valve in the Y pipe that connects the two turbos. Charge relief vents the secondary turbo back to the airbox during prespool.

Mazda part # N390-18-7410 is the first turbo control solenoid, in the rats nest
Mazda part # N3A1-18-7410 is the second turbo control solenoid, located near the ACV

The turbo control valve is sort of like the twin scroll valve on the series 4 Rx-7. On the series 4 there was a vacuum actuator to switch the turbine A/R and close one of the scrolls. On the FD the turbo control valve opens the secondary turbo. It has a vacuum side and a pressure side, so it needs two solenoids.

The other two solenoids, precontrol and wastegate, control boost during primary turbo and primary + secondary turbo operation respectively. They rarely fail. I do recommend you switch to 3 port solenoids, similar to what is used in the aftermarket external controllers. You can either buy a separate aftermarket controller (TurboSmart, AEM, etc) or use MAC part # 35A-AAA-DDBA , which you can get on amazon:


The precontrol/wastegate connectors are from AMP/Tyco. You can wire them in to the MAC solenoids with this pigtail (2 needed):

https://www.bmotorsports.com/shop/pr...oducts_id/1674

IRPerformance

iTrader: (41)

The power fc doesn't have the proper datalogging capabilities to safely remote tune in my opinion.

DaleClark

iTrader: (55)

For stalling I would also make sure you have a working dashpot. This "catches" the throttle when you let off the gas and eases it closed. A bad/stuck/misadjusted dashpot will cause stalling.

Dale

FrankV702

iTrader: (14)

So today I went to change my plugs wires.. couldn't figure out a way to do it with the UIM on (crazy how the stock cools are just sitting on top of the engine in all that heat) and a BUNCH of vacuum hoses, the check valves and a few solenoids broke right off. I removed the air pump,and started on putting some block off plates. It's been so long since I've messed with a completely stock rotary that all those vacuum lines and solenoids were intimidating me! Haha. I think the turbos might be on their way out. I had my heart set on BNR stage 3 twins for a while but I've been watching a lot of videos of those new BW EFR turbos. I think I might go with one of the EFR 7670 turbos for quick spool and enough power for me.

FrankV702

iTrader: (14)

So I bought new solenoids, some silicone hoses, and the viton check valves from Dale Clark. Removed the air pump, acv, all the emissions solenoids and replaced all vacuum hoses with the silicone ones. It drives and idles like a dream now. Boost is a little over 11psi so it's creeping slightly but it feels really good. The vacuum hose for the charge relief valve was pinched, brittle, and turned to dust when I touched it.

arghx

iTrader: (3)

Is it catless? Glad to hear new solenoids, hose, and check valves are working well for you.

FrankV702

iTrader: (14)

It has the stock midpipe with cat but an HKS 3" downpipe and 3" catback. I'm going to switch to a 3" midpipe pretty soon, just trying to decide if I should go with a resonated midpipe or not. I don't want it to be obnoxiously loud. I'd like to hear a car in person with either to decide.

arghx

iTrader: (3)

I mean dude a straight pipe with an N1 is basically chainsaw status

FrankV702

iTrader: (14)

haha, yea, that's what I'm thinking.. I'm pretty set on going with a resonated midpipe. From what I'm reading, there's really no decrease in performance but it keeps it somewhat quiet. The car is not loud at all compared to what I was expecting.