JZ is sick :(

[annoyingrob]

I haven't had any time to troubleshoot this, as I was on my way to work when it happend.

The problem started last night I suppose, I was leaving my friend's house, and the car wouldn't idle properly. It kept stalling. On the drive home (about 2 miles) I noticed my wideband was reading off-scale rich, but it evened itself out by the time I got home (My ECU will auto-tune from wideband feedback)

This morning, again, idle issues, but it was idling at a slightly more normal 11:1. Driving, it was about 14:1, where it should be, but the car didn't feel right. It was like something was pulling it back, kind of like the e-brake was on or something.

I drove it to the end of the block, and turned around, and parked it.

What I noticed:

First, the exhaust manifold was RED hot, after a few minutes of diring
Second, it was spooling REALLY rast, like 15psi by 3k. It was impossible to keep it out of boost.
Third, at high boost, it started to backfire.
Fourth, It may be my imagination, but my exhaust seems louder. I think it might be leaking from the back of the turbo.

I took off the intake piping, and the turbo spun freely.


My guess right now is the car's either running stupid rich, or stupid lean. I'm guessing rich, I've drivn the car lean, this doesn't feel the same. I cranked up the fuel pressure a few days ago, but it was driving for days with no problems, so I'm not sure if this is related. It's possible maybe my wideband sensor has gone bad, and is sending bad numbers to the ecu, but I don't know for sure.

Any guesses?

 

[SupraStardom]

do u have a catalytic converter on your exhaust system? i remember having a car that had a fouled cat and i couldnt drive up hill it was bogged down. and the exhaust manifold was running hot like that. as for the spooling thing...im not sure

 

[viperkillertt]

Wideband probably isnt bad. If it feels weird and it reads weird, it probably is weird.

PS. Sorry to hear she is sick

 

[suprahero]

Is their any way that your timing got messed up?

 

[annoyingrob]

do u have a catalytic converter on your exhaust system? i remember having a car that had a fouled cat and i couldnt drive up hill it was bogged down. and the exhaust manifold was running hot like that. as for the spooling thing...im not sure

No cat.

and the only way the timing could have been messed up would be if the timing belt slipped, which I doubt it did.

 

[tlo86]

No cat.

and the only way the timing could have been messed up would be if the timing belt slipped, which I doubt it did.

you would really notice if it did slip though you prolly wouldnt be able to rev heh, at least not rev very high

 

[Supra-K]

sorry to hear that dude, so like a crappy situation, not much help here sounds pretty advacne for what I know but best of luck from here man!

 

[T701jz]

Check your exhaust timing. Like supra-k said.

 

[hottscennessey]

sounds like timing issues

 

[pbasil1]

Sounds like timing has been retarded big time... T Its combusting in the header which is keeping the turbos spooled and making them very hot.

 

[WeDgE]

Did anti-lag get turned on by chance?

 

[annoyingrob]

I did a little more troubleshooting this afternoon, and it does indeed seem like an overfueling issue.

I sat there for like half an hour, and finally got it to re-learn its idle. It's driving a lot better now.

I think what happened, is the night I left my friend's, there was a freak snow storm. My cold start enrichments aren't properly programmed that cold, on top of the increased fuel pressure as of late, just created a problem with too much fuel in the motor.

On the downside, my manifold is cracked now.

 

[bloodasp90]

well thats never good to have a cracked manifold, time to get the welder out?

 

[annoyingrob]

well thats never good to have a cracked manifold, time to get the welder out?

Funny you mention that. My tax return is going towards a new MIG/TIG.

 

[viperkillertt]

Funny you mention that. My tax return is going towards a new MIG/TIG.

Sweet! Toy Time!

 

[annoyingrob]

I came to a realization today on the way home. I was cruising normally, then decided to boost it to see how rich it was running. hit 15psi, running about 10:1, started sputtering a little from too much fuel. I let off, then stopped at the next light where the car just died on me. Was running too lean at that point.

Hmm, too rich, then too lean? I crank it, hearing this unfamiliar whine from the hatch area........

I'm almost positive one of my fuel pumps is on its last legs. Sometimes it will work fine, providing lots of fuel for the motor, sometimes it dies, starving my 2nd pump from fuel. Tomorrow I go buy a brand new Denso pump, and drop the tank. Ugh. I have almost a full tank of 94 too.

It MIGHT be a clogged fuel filter, or pickup sock, but I have a feeling it's probably the pump. Yes, I will check the other two while I'm at it though.

 

[annoyingrob]

Car is running well again!

I bought a JZA80 pump, and installed it. Wow, is it ever easy to drop the fuel tank in this car. Now it's running pretty good. It's flowing a lot more fuel than the dying pump was, so all of my tuning is now running on the rich side. That'll auto-tune itself in short order though.

lol, I only make 10psi because it's running like 9:1 when it gets into boost.

The old pump, which was replaced by the old owner just before I got the car, looks like some sort of no-name Denso. It's physically very similar to a Denso pump, but there's no markings on it. No wonder it failed.

 

[viperkillertt]

Car is running well again!

I bought a JZA80 pump, and installed it. Wow, is it ever easy to drop the fuel tank in this car. Now it's running pretty good. It's flowing a lot more fuel than the dying pump was, so all of my tuning is now running on the rich side. That'll auto-tune itself in short order though.

lol, I only make 10psi because it's running like 9:1 when it gets into boost.

The old pump, which was replaced by the old owner just before I got the car, looks like some sort of no-name Denso. It's physically very similar to a Denso pump, but there's no markings on it. No wonder it failed.

Wow, 9:1, damn, can you actually watch your fuel gauge go down?

Glad to hear she is all well now!

 

[suprahero]

I'm glad you've got the bugs worked out. Hopefully no more gremlins will find their way into your car.