Cascade Crew

Raiden · Member Joined: 10 Mar 2004 Posts: 193 Location: tacoma

I was having some wiring issues with my Z which turned out to be due to the wrong tail light bulb! I thought my idle issues was due to a short. Guess not!

A few weeks ago, I noticed my car started running poor. During curise speeds and part throttle, it seemed to run ok. As soon as I put my foot down @ WOT, my Z ran as if it was not getting timing or way too much fuel. I limped it home, got it into the garage and then it would not start! Turns out my ignition switch was bad. I fixed that. Now, my car will hardly hold an idle. I have many extra parts and replaced my map sensor, ignition module, plugs, cap/rotor, wires, coil. No change. fuel psi is 43.5. timing is 12deg advanced as it will run for about 45seconds with this timing. I usualy run 8deg advanced.

A few symptoms I have noticed was that if I leave my key on, engine off, my fuel psi goes to 43.5, the in 2 minutes, it drops to 30psi. another 10 minutes later, it drops to 20 and eventually to zero. After I noticed this, I inspected my fuel pressure regulator....It looks fine!

Also, when my Z does run, it's pig rich. There's a black spot on the garage floor where the exahust dumps out. I spray engine starter fluid on the mating surfaces of the intake with no change in idle quality. She sounds like she's running on 6-7 cylinders. Wires are in correct order.

No codes.

HELP Crying or Very sad

Dewey316 · Posted: Mon May 28, 2007 7:15 pm Post subject:

Craig,

TPI right? What year is it? Also, do you still have teh supercharer on it? does that have any sort of fuel enrichment system that could be coming into play when it shouldn't?

Raiden · Member Joined: 10 Mar 2004 Posts: 193 Location: tacoma

Sup D!

Yea, I still have the s/c on it but as for now, I have my FMU blocked off so it's not working till I resolve this problem.

91 Z, tpi engine, ford 30lb injectors, lpe 214 blower cam, afr 190 heads, crane hi 6s ignition.

I've tried to run it with and without the crane box...no change:(

Dewey316 · Posted: Mon May 28, 2007 8:20 pm Post subject:

do you have scanner, to check things like what the coolant temp sensor is reading?

I would also go around, and pull plugs and injectors 1 at a time, to see if you can isolate if a cyl is mis-firing.

Raiden · Member Joined: 10 Mar 2004 Posts: 193 Location: tacoma

Dewey,

I can t even keep it running long enough to disconnect the injectors one at a time! My plan is to pull the runners off, activate the fuel system and watch the injectors for leakage. I may purchase one of those fuel injector cleaner kits before I tear it down.

I have CM software and every sensor seems to be working fine.

Sellmanb · Member Joined: 30 Nov 2004 Posts: 727 Location: Tigard, OR

I'll 2nd making sure your coolant temp sensor (one the ECM uses, not for gauges) is reading correctly.

I've also run into problems where a total misfire on one cylinder will make the O2's (which shouldnt be effecting ECM output until warm up) think it's running way too lean (since O2 sensors only read oxygen amounts, not fuel amount, it reads that cylinder pushing out nothing but air and assumes it needs a whole lot more fuel).

Do you have EGR on this vehicle?

RSFreak · Posted: Mon May 28, 2007 10:55 pm Post subject:

Hey Craig, I know this is pretty basic, but have you looked at the plugs? Also, you still got the cat on her?

Raiden · Member Joined: 10 Mar 2004 Posts: 193 Location: tacoma

I have CM software and all sensors are reading fine. plugs are black.

I plan on removing the upper intake today, pulling the injectors and then turn the key on and watch for leaks from my injectors.

Also, when I turn my car to the on position, my fan runs, WHat's uP with that???

BigDaddyVu · Posted: Tue May 29, 2007 8:33 am Post subject:

You guys need to get the book " Chevy TPI Fuel Injection Swapper's Guide" It includes GM mechanic trouble shooting, parameters, and how to tpi for dummies.

Dewey316 · Posted: Tue May 29, 2007 8:38 am Post subject:

Your Z car is also a 91-92 isn't it? Have you checked the line to the MAP sensor, to make sure it hasn't got a small crack in it?

Raiden · Member Joined: 10 Mar 2004 Posts: 193 Location: tacoma

I have a total of 2 extra map sensors. All work fine.

Now, the saga continues. I jump my ab on the ALDL port and Im getting NO FREAKING check engine code light at all! Evil or Very Mad

Dewey316 · Posted: Tue May 29, 2007 10:21 am Post subject:

have a spare ECM laying around?

Xophertony · Posted: Tue May 29, 2007 10:56 am Post subject:

Raiden · Member Joined: 10 Mar 2004 Posts: 193 Location: tacoma

BigDaddyVu · Posted: Tue May 29, 2007 2:55 pm Post subject:

Raiden · Member Joined: 10 Mar 2004 Posts: 193 Location: tacoma

Well, that is interesting about the ford svo injectors. I've ran them for 10 years, 24's 30's and 36's. I have never had a problem with them. If I would have konw that, I would have used some accels'.

that aint the problem. My aldl port has no power to it at all. I'm getting no codes and gonna pay out the nose to get my car running again Rolling Eyes

Raiden · Member Joined: 10 Mar 2004 Posts: 193 Location: tacoma

Well, after working a but load of overtime the past 2 months, I finally put my Z back together. My ohms on my injectors were fine, but the internal workings on 3 of them were messed up bad! They would leak when the fuel rail was pressurized. I replaced my injectors, had my heads looked at and I had a 20% leakage on no 5 and 7 valves. I had the valves repaired and finally got it running. runs great so far. I"ve yet to take it for a spin. Still working OT like a mad man. So it turns out bad injectors and two leaky valves caused my problems. I just wanted people to know incase this ever happend to anyone here;)