Yesterday the seven just started idleing real funny, I'll do my best to describe it, unfortunately I have no means of letting you guys hear it, but it's really tickin me off! (apologize for the 12yr old description beforehand) Before the engine would idle fine, sitting around 750rpms, just going chug.......chug.......chug.......chug...... but now it's idleing a little lower, around 680, and it's going like this chug..chug..chug..chug.. like double time! Sorry for the bad description, but that's the best way to explain it, like a harley pulled up next to you! It's shaking pretty bad too. Any ideas?

 

Check for vacuum leaks- they are notorious for bad idle. My 'vert did something similar, only when cold- I found that the pcv valve just under the primary fuel rail had come apart, and the two halves were JUST BARELY separated- took me almost an hour to find. So yeah- vac leaks are the primary suspect here.

 

This isn't just a cold issue, it always does it. I just got brand new lines put all over it not too long ago..... but that was my initial thought as well, I'll search again though.

 

prob vacuum, tps?

 

How does it run otherwise? If it runs great throughout the rev range, it is most likely a vacuum leak, I would say TPS, but sensors don't just adjust themselves.

If it has loss of power, it could be bad compression.

 

no loss of power, except right off the go at a stop it seems like it bogs down just a bit. Sputters under boost at high rpms, I'm still searching for vac leaks (what a pain in the ***.) Anyone got a trick to finding one besides the carb cleaner trick? I'm getting a TPS in the mail shortly to fix other problems..... gotta love these cars! Oh yea, dumb question, but what would happen if you hooked up the coil packs wrong to the plugs, like trailing pack to leading plugs, etc?

 

stock top mount still??
i seen a pots form NZconvertable in which titled PVC plastic and compressed air to find leaks...looked like a great and easy way to find them.

 

thanks I'll search for that, no I've got a greddy FMIC.... coil packs are stock though.

 

It sounds like it is a vaccume leak. I had one a little while back because when I was putting the fuel rail back on the car one of the big rubber o-rings fell off the bottom of the injectors. Mine was sputtering under boost as well, however that being said, I would avoid boosting it untill you fix the problem since some vaccume leaks (the one I described for example) can cause a lean a/f mix and possibly detonation.

If you hooked up your coil packs wrong you would probably be detonating pretty bad too since the leadings fire a waste spark.

 

Vaccuum leak... check all lines, intake gaskets, and fuel injectors/rails for air leaks... should fix it... had the same problem..

 

ok... so i crafted together some PVC and a pressure regulator and checked for vac leaks per NZconvertible's method on here and found this:

1) there is a hose running from what I think is the ACV coming up from near the turbo that is gushing air, I don't know if this needs to be blocked off or not, blocking it off had no effect towards the running problem. However, I had to block it off to find:

2) a leak coming from an intake piping sleeve, from the intercooler to the throttle body, there is a nasty like almost 180* bend into the TB, and when the system was pressurized at 10 - 15 psi, that is when the leak became evident. I replaced the sleeve with another and still... no change with my issue. Since the leak only came about w/ 10 - 15psi, I'm thinking that would have made little difference, but it would explain some sputtering at high boost/high rpm's....

besides the above "leaks", I couldn't find anything! If it makes any difference, every once in a while, while cruising in 5th at say 70, the AFR's will spike up to mid 17's to low 18's. I can downshift to 4th and it goes away, then shift back and it's fine....

So, I'm stumped! I've got a video and some pics that I am waiting to upload, I will update with those ASAP. The engine shakes like mad! I'm not getting any CEL's except for OMP, which I am replacing tomorrow.

Could the bad OMP CEL have fried my ECU, and that is what is causing this? How can I check to see if it is indeed my ECU?

 

I've replace the TPS..... the only thing I can think of is some one way check valve..... i'm going to take apart the UIM, look for the PCV that Introvert said..... man this is pissing me off! I WILL PREVAIL! BTW, introvert, whats up with that FD pulley?

 

i would ay low compression on one rotor. slightly chipped seal.. mine did that just before it went pop

 

Mine did that when I forgot to plug the MAF sensor back in. It also smoked a bit during this. Plugged it back in and everything went back to normal.

 

compression's good, MAF plugged in, c'mon....... It's gotta be a vac leak..... still searching.

 

ok.... I've narrowed it down to a major culprit: the brake booster.
the boost guage bounces around a little during idle (gotta be a vac leak, right?) and even more so when i pump the brakes, idle increases too, so *lightbulb* that's where I'm checking tomorrow. It's been freezing and raining for the past week so I haven't been able to check it out. Gratuitous, uneccessary post I guess. Yea yea I know, don't ask us about something unless you've looked for a problem or tested something.... blah blah blah. I've just been watching videos of blown 13b's and it's freakin me out. I'll post tomorrow with results.

 

Sounds like the plugs. Clean them or buy new ones. de-flood the engine while your at it.

 

Well I finally figured out what went wrong! Chipped an apex seal
I tested the compression and sure enough the rear rotor showed low compression on two faces.... I pieced together what happened after finally fixing my MOP:

- MOP went out which eventually fried my ECU
- replaced the MOP and then my ECU "woke up" and sent out another CEL...... the knock sensor!
- checked the knock sensor and the wire that was neatly tucked back and almost invisible had sheared off of the connector

So I wasn't aware my knock sensor was out because the MOP was messing up the ECU, my guess is that I detonated, blew the seal, and now need a rebuild! Just in time for my megasquirt to arrive! Kevin Landers, where you at?

 

yea when i just blew my motor two weeks ago it ran like what your describing, took her apart and two apex seals had just a small lil peice of the corners broken off.

so little that every other part in the motor is still fine