Definitely let us know if the TPs fixes the problem. I would love to have my car running and running correctly.

 

So you have a S5(91) car and a S5 (JDM) engine.
Okay your problem might be just TPS.

Batman and me have a S4(87-88) car and a S5 (JDM) engine. We might have a different issue than what you have.

 

I don't see ours being that TPS as you said you have changed and checked yours several times and I have also done the same. I have checked vacuum leaks, TPS, timing, everything I can think of or have been told to try and nothing has worked so far. Hopefully one of us can find out. I'm going to try working on mine some more tomorrow since I am at work today. If anything just so happens to fix it I will definitely let everyone know.

 

I am thinking about taking off the whole intake, UIM and LIM. I need to really look at how it mates from a S4 LIM to a S5 block. I believe the engine is getting more air than it should that's why the CAS has to be retarded.

Took these pictures a month ago of the turbo exhaust. What does the color mean.

 

Not sure about the color. You have switched the whole upper and lower intake manifold? The only thing I have changed over is the TPS on the intake. I didn't actually switch the manifolds.

 

I have S4 manifolds on the block.
The next thing I am gonna look at is the big black gasket or whatever you call that thing between the TB and UIM. I have noticed that at the bottom of the gasket there is a square hole. So air is actually bypassing the throttle plates.
Then I noticed on another UIM that I have the square is blocked.
In the picture this is the other UIM i have, circled in RED is what I am talking about. This one is blocked, the one that's on my car now that whole is open.

Batman is yours blocked like this or is it open.

I am gonna put the one in the picture on and see what happens.

 

Mine doesn't have the square hole like that. I did tweak with the adjustment on the TPs a little bit today, it helped quite a bit. No more bucking while driving, the engine doesn't shake about and seems to run very smoothly now, also the timing is about where it should be not all the way to retard. Problem now is that my idle is somewhere around 1300 rpm. I didn't get a chance to see what was causing it because it started raining. Any idea what it could be?

With the TPS I couldn't get the voltmeter to read correctly so I basically left the car idleing and just turning the adjustment screw slowly until the car started running much much smoother.

 

I say turn the screw that adjusts the plate in the throttle body until the rpm gets down to what you like. You have to use that since you don't have a BAC to adjust the idle. Then recalibrate the TPS with the volt meter and you should be good.

For me I am gonna put on the big gasket like the one in the picture and see if that fixes my problem. I always wondered why there was a hole in the first place.

 

I'm telling you guys its your TPS! If we all have the same issues then I believe it is TPS related. I only strongly believe it since batman said he adjusted his TPS and his issues pretty much disappeared other then a higher idle which is likely because the TPS is dying and has been compensated by a higher then normal idle to stop from bogging out or dying while clutching in.

My problems got better after my TPS adjustment when I first got the car but because the deadspot is still there, it won't truely disappear till I get a new one that is problem-free. Unfortunately the stock TPS is plunger-style, so unreliability is common (according to what I've read). I'm assuming a Standalone EMS with it's own TPS unit will solve this.

P.S.

Is it safe to assume that the passage in the UIM is a coolant passage? I'm unsure and would love to know!

 

That passage is definately air not coolant. If you look at the TB from the front you will see a round hole at the bottom, that runs the length of the TB to the back. Air is bypassing the throttle plates and going into the UIM. Batman says the thick black gasket between the TB and UIM on his doesn't have a hole in it. Once I put on the gasket that doesn't have the hole we will see.

I hear you about the TPS, Batman might have that problem. I have 2 good ones that don't have any dead spots.

Let us know when you change your TPS

 

Ah, I see! It just seemed odd that they would have that passage there and then have a gasket that covers that hole? Does it not continue into the LIM? Haha, very odd. You can probably tell I'm still learning a lot about the 13B and Rotary motors in general, =p .

Absolutely! I'm quite excited for next week seeing as I'm so tired of this deadspot and the decelerating throttle jerks.

Cheers.

 

Yeah it's weird to me also. UIM in the picture with the hole closed on the gasket is what came with the S5 engine. I used the UIM that I had from the S4 engine with hole in the gasket and put it on the S5 engine. So I am hoping that this might be the reason for my issues.

It's taking me awhile to figure all the tricks with these rotaries too.

 

Mine definitely seems to be the TPS. After I adjusted it the car runs fine other than the high idle. I can push the TPS plunger in with my finger while the car is idleing and it starts to stumble and idle badly, causing the motor to shake like my original problem. I'm going to try to reinstall my BAC and see if that fixes the high idle, if not I will try a new TPS. I can't say for coolmike, but I don't have the whole in the TB spacer like you shown in the pics above. That may definitely be why you car is acting up.

 

Yeah i guess that should be my problem. Gotta wait until my brother sends it to me from VA next week.

 

does it die when you come to a stop

 

Batman,
Do you have the S5 UIM and LIM onyour engine?
I have S4 UIM and LIM on mine.

 

I don't know much about T2 motors but could the low idle at start have anything to do with the thermowax? Just a total guess.

 

I have the s5 UIM and LIM on my car. The only thing I switched over from the s4 was the TPS and the injectors.

 

Maybe that's where I messed up. I got the UIM that came with the enigine, just gotta find LIM and put them on and see what happens.

 

The only thing I had to switch on mine to make it all work was the TPS as far as the manifolds go.