Getting it running is the hardest part, nice

 

Yeah now if i could only get it to run right. I just want to drive it already!

 

yeah, check the exhaust joints (engine, turbo and downpipe) and make sure everything is tight and all gaskets are intact.

it's definitely worth following that train of thought. vacuum leaks can be very insidious things. they suck! (get it )

i think you may be in the final stretch, and you're going about it the right way - being thorough and methodical.

 

I think you'll be driving it soon man. Assuming that you have no leaks I think it's a good time to revisit the TPS and idle screw. You did touch the throttle body so I wouldn't be surprised if your tps needs adjustment.

 

Well its not a vacuum leak. Sprayed everything with soapy water and didn't see a single bubble.

I tightened down all the exhaust stuff and it still ticks. My girlfriend says the ticking is coming from the front of the engine though. So i guess that ruled out the exhaust. There must be something vibrating around. You can only hear it while its running rough at low rpm. When i bring up the idle a bit and it smooths out, the ticking becomes much more quiet.

So whats left? We are getting air with no leaks. Getting fuel as it should. The engine has plenty of compression for a fresh build. That leaves spark.

It still pops like its misfiring. I wonder if its getting good spark. Is there a way to check the coils?

Also here is another video. Might be hard to hear, but i was trying to get a video with how much it pops.


EDIT: Bought a spark tester to see if the plugs are getting a good spark. Should be here today. If this comes back good I might just start driving it and see if putting some miles on it changes anything.

 

Didn't get to check the spark last night. I guess Amazon 1 day shipping means they deliver it at 9pm. I still took it for a drive though! It was a very short drive but a drive non the less.

It was very sluggish. I may have been over babying it though. It started to smell bad like something burning so that's what caused the short drive. That's probably normal though and I'm just being paranoid.

After that short drive and adjusting the tps it now idles at around 600rpm. Not perfect but at least it keeps itself alive right now. Though once I touched the throttle it immediately died. My hope is to actually drive it a bunch this weekend and see if things improve.

 

It sounds like you have to set your throttle valve. Open it up a bit more and readjust tps. You'll be goin back and forth for a bit because tps settings change when you adjust the throttle. It is a pain but youll get it.

 

Throttle valve? Do you mean the idle adjust screw that sits under the intercooler? I maxed that one out for now.

 

You're S4 right? You should review chapter 4B page 81-82 in FSM.

 

Alright I checked it. I don't have a bac so that part obviously didn't apply. I did mess with the variable resistor though and found out it's broken. One of the cars previous owners must have broken the stops and now it has no continuity between pin a and c. I read that when they break they default to lean mode. When it was N/A it probably didn't care that it was lean. Now that it's turbo though it may be causing problems. That being said I think im running very lean. My afr is 14.5 at "idle" (which I can't get it to idle on its own again) and when I rev it the afr doesn't move at all and it back fires.

Guess I'm in the market for a variable resistor now.

 

Does it buck when you try to drive it? Are you sure both rotors are firing? Pull the plugs, have a look.

Also have you double checked your plug wires?

 

I've only been able to drive it once. It didn't buck but it was sluggish. Both rotors are firing and the plug wires are right. Spark plugs are really oily when I pull them out. I think im premixing too much. Blue smoke never stops coming out of the exhaust.

 

how much are you premixing? What ratio? What oil? Have you tried new plugs?

Edit: I jsut saw your compression numbers. Super low. You probably need to break it in

 

100:1 with idemitsu pre mix. This is with an omp as well but I heard they take some time to prime which is why im using a ratio more common to engines with no omp. The plugs only have about an hour of run time on them so I'd think they would be all right.

Yeah I figured the compression has something to do with it but it's hard to break it in when I can't even get it to idle. To make matters worse it won't start when it's hot because of the low compression so if it stalls while im out driving it, I'm pretty screwed.

 

Bring a friend with you and drive around the block a bunch of times so you can push it home if you have to.

I've read some people put ATF in the housings to help with the low compression when youre starting it..

 

Thinking about this -I would say, given your compression values that trying to set your idle could be a wasted effort. Your compression is changing every time you run it.

Set your idle high and let your car idle for a few hours making sure that your temps are in check. Like literally 3-4 hours. Hold the throttle at different rpm. It'll help break up the boredom and it'll help with the break in. Nothing beats road time though but idle is obviously better than nothing and might be your only option. It takes a long time to break in the irons especially if you left the glaze on.

Have you read what Aaron Cake has to say about this? If not it would be worth your time to do so.

 

I adjusted my throttle cable so that the throttle plate is always slightly open. I didn't get a chance to test it last night but I have hopes that this will keep it alive for the time being. I can't get it to idle on its own again any other way.

Im interested to read what Aaron has to say but I couldn't find a thread or anything on his site. Got a link for me by chance?

 

https://www.aaroncake.net/

 

I don't see anything that pertains to engine break in on his site. Am I overlooking it?

 

Apologies, I meant this:

https://www.rotaryresurrection.com/2...p_breakin.html

 

I guess I'm just rushing it too much? Though according to that site I should have been able to get some kind of idle with just the idle set screw. Oh well. Hopefully the adjusted throttle cable will do the trick for the time being while I put some run time on the engine.

 

Sorry, I haven't had a chance to read the whole thing yet, but did you check the timing? I've had some that sounded similar to the popping from my timing being off. It can also cause idle problems and sluggishness.

Also, I wanted to chime in that you need to see it through and not rush it. I've been through way too many engines in my nearly 2 decades of rotaries, and all but one of them were because I rushed things. Hang in there, you'll figure it out!

 

I did check timing a week or two ago but I decided to look again. I couldn't get it to go below 1k though, probably because the tps never got adjusted after messing with the throttle cable so it was way off, but what I did find was that I don't think my rear trailing plug is getting spark. My timing light would not flash on the rear trailing plug wire. Coil is firing though. Tomorrow im going to switch the plug wires and see if the problem follows the wire.

I also found an oil leak on my turbo so I can't just let it idle unsupervised until I get that taken care of unfortunately.

EDIT: After reading more it looks like trailing spark doesn't really account for much. So I doubt that's part of my issue. Still going to fix it, but I doubt it'll make a difference.

 

Car is idling perfectly now!!!

I ended up pulling my turbo off this weekend because it was smoking so much I thought it may have been blown. Well it isn't, just leaking from every inlet and outlet. However while I had it off I decided to tighten down the lim bolts and low and behold I forgot to put in the middle upper bolt.

So it ended up being another hidden vacuum leak the whole time.

Was about to take it for a drive but the rubber coolant return hose just ruptured. Waiting for it to cool and then replace it.

Thank you everyone that has stuck with me through this and shared your knowledge and suggestions. I can't thank you guys enough.

I'll post again in a couple days to let you guys know how the maiden voyage goes.

 

Lol you got LIM-owned.