Ok so ive had my car for like 4 years now and ive had my fair share of issues but this one has got me stumped.

First off, its randmom.....the best kind of problem, the camaro is missing if i hit WOT towards the upper half of the rpm range, easing into it i can go thru the whole range, sometimes its just a slight miss sometimes it feels like the motors gonna blow up on me. Ran a FP test got 11 psi on the inlet line, while the problem was occuring, under load, idle, no change so im confident that everything from the inlet line back is good, i replaced my entire fuel system like 2 years ago.

My friend hooked up his tunerpro setup to the car when this first happened, he read forced open condition, lean condition, MAP code (MAP was reading at 1.3%) and my CTS was reading at 26*F..... right off the bat i replaced the IAC because this happened last time my IAC crapped out, after seeing his readings i swapped the CTS and the MAP, car ran great for a day, went home, next day same crap. i havent checked the timing yet but thats getting done today, i feel that if it were base timing though it would be a turd all through the rpm range.

I need some help here, finally convinced my wife to let me finish my 5.7/t56 swap and now i have to throw money at the current motor.....

In any case heres a link to the post i put up on cascade crew, flip thru it, ignore it whatever i just need some help, if i left anything out youll find it in this thread


http://cascadecrew.org/phpBB2/viewtopic.php?t=8363

TIA

 

It sounds like your fuel pumps going out. How many miles you got on it? My brothers truck just suffered the same issues (TBI 92 K1500). It ran like it wasn't getting enough fuel for about a month then one day he went to start it and nothing, pump finally went. He had 200k on it.

 

Pump only has about 30k on it, I thought the same but the fp test showed different, if the pump was going out it wouldn't have stayed steady under load while the problem was occuring, if it is fuel and not a sensor it would have to be injectors or regulator, regulator was replaced along with pump the injectors are the only original, but they're still putting out an even cone pattern

 

Last fall I had similar issue, runnin lean. Barely runnin as very lean. Replaced the FP and filter. That was not it. It turned out to be MAP sensor and car ran OK after its replacement. I had no CE light nor codes. Can you clear codes and see if you can find a code once more?

My IAT failed 10 years or so ago. It just caused a low idle on warm up. Died seated. If retracted a high idle would result. Maybe on key off it seats. And that was its last breath.

 

I cleared them after replacing the map iac and cts, reset minimum air and then got code 32 the next day, cleared it and then it hasn't popped a light since

 

Tested plug wires for continuity? Maybe a plug wire is trying to slip off the plug - I had one do that - stay on the plug, but no real metal to metal contact inside the boot - had to crimp it a tad with needle nose pliers to make it 'click' and stay on. That made my car have a "random" miss at WOT only.

 

hmm... never checked that....im gonna smack myself if thats the case lol ill be like 100 in the hole over a stupid plug lol ill have it running and wiggle the wires, see what happens, can i just use my dmm for testing continuity? just go from the cap side to the nut side of the plug?

 

just as an update to everyone i figured it out, maybe this thread can help someone who searches their issues later lol

clogged injectors, swapped my injectors for another set of tbi injectors, bought the tbi rebuild kit from oriely and tore it down, cleaned, and rebuilt it, viola problem solved, clogged injector filters apparently cause bogging and backfiring when pushing the gas

 

Glad you solved the problem and even happier you shared the diagnosis! Some guys get it fixed and don't care enough to follow up with the answer, that just pisses me off!

 

Oh yeah trust me, I spent plenty of time using the search feature, its really aggitating when you spend time reading a thread to come up with nothing, it used to be a lot better around here but I've noticed it slip downhill lately so I don't usually use tgo much anymore for my problems for that specific reason, I wish mods would go thru and delete useless threads with no answers or put in a solved/unsolved box for the search engine

 

YES!!

But I also noticed you said you checked the injectors once and they were fine.. Not bashing just found it a bit..funny..

Nice to hear though since I have TBI myself..the car has been sitting for 4 1/2 years and I expect some type of fuel problems with that nearly 5 year old gas in my tank.. Just going to Seafoam everything.. Oh did you try Seafoaming before replacing them?? I know this cleared out my 300zx injectors and even brought back injector tick (VG30's are known for injector tick..lets you know they're working lol).. Well take care..

 

That was an error on my part, I figured if and iknjector was clogged it wouldn't spray in a cone pattern, I visually checked them and assumed they were good, which they weren't lol I can clearly see the difference with the new ones though

I seafoam my caR almost religiously, the gas up here sucks compafred to az gas, when I changed my filter a few weeks ago it was coming out the inlet nside almost black, tank was extremely clean though, it just broke down the crap and shoved it further up the lines to the filter around the injector itself, I could see chunks on the smaller filters which should have been expected when seafoaming so much,I knew it had be to in the tbi though because with the pressure check I got 11 psi on the inlet line consitentl and the tbi unit was the only thing not in line with the test

 

Ahh..nice.. I plan to Seafoam mine and it seems I may want to get some new injectors as well just in case..or at least the rebuild kit.. Thanks for this..