We have an 86 iroc z with a 305 tpi system. the car sat for a while but was still driveable albeit slight power loss. had the front end redone and alignment fixed also replaced the spark plugs and it ran great for about 2 months. one day the car just died out as it was driving and had a serious loss of power. every time the throttle was pushed the car would bog down and die. we have changed the MAF sensor, IACV, TPS, fuel pressure regulator new gaskets on the intake plenum and throttle body fixed a vacuum leak that went into the throttle body redropped the distributor new cap and rotor new fuel pump new plug wires set the timing new ecm, checked the cat for clogs and a new fuel filter. now after setting the timing the car will not hold an idle nor will it rev higher than 3500 rpm even when flooring the throttle it takes about 2 minutes for rpm to get that high and back fires really bad. once the throttle is released the car will instantly sputter out and die. it sounds like it is missing and starting to think its piston rings or some compression problem. anyone have ideas because i cant think of a thing anymore. also note the diagnostic system is fried and wont send a code because it shuts off when trying to get a read.

 

If you think it may be compression get a tester and test each spark plug hole. While each plug is off test the spark at the tip of the plug as well to make sure youre getting good spark. If it doesnt run while cold or hot check fuel pressure and or test your injectors.

 

injectors were checked last night and all seemed fine. going to have to get a compression tester in the next few weeks and check that. also should the fuel pump be audible and constantly running because the car burns very rich and has a strong smell of gas. pulled a plug out last night and it was pitch black.

 

Someone else had gas leaking off front of motor. Worth checking few posts below yours. https://www.thirdgen.org/forums/tpi/...l-exhaust.html

Recheck all plugs. If its black then may not be burning. Especialy new plugs already dirty you have a serious air fuel prob.
Fuel pump turns on for about 5 secs at key on to prime.
If you smell gas, from where? Engine bay? Cab? Rear of car?

 

well the guy who owned it before rewired the fuel pump to a switch and when that is on its constantly running the fan was also wired to a switch too. before the pump was replaced it did not require the switch to function. i am smelling the fuel from the engine bay its a very strong smell. could it be its not getting a spark somehow.

 

Wow what switch is it tied to?. If you lose oil pressure your engine may not shut down the fuel pump when below 6psi oil. And even worse if you get in an accident, your car stalls; but fuel isnt hooked up to oil anymore so when your motor stalls nothing tells the fuel to stop pumping unless you key off. Now if your fuel system is leaking from the wreck you better run upwind.

If youre backfiring either not burning fuel or timing is too advanced.

 

lol wish i knew what it was wired to the wiring in this car is an abomination. kind of thinking thats a major issue too but idk. getting in a wreck is the least of my worries seeing as how the car wont move. i get good oil pressure and the timing is set 6 degrees before tdc like it says in the haynes manual but its still not burning. im thinking its getting too much somewhere at the injectors. thats why im thinking the pump might have something to do with it.

 

Replaced pump meeting factory specs?

 

well we replaced it the way we read in the book and we have adequate fuel pressure which i believe was 45 psi so the pressure seems fine. it just doesnt make sense.

 

I read the CTS(coolant temp sensor) willgive rough idle. Test it or buy one. Its next to tps and iac. Since you changed the timing try retarding some. If youre sure you got pressure to injectors AND youre sure you got spark coming off the spark plugs, then atleast you got fuel and spark.

Maybe it might be a good idea to resolve hacked jobs starting with SES diagnosis. Especialy with car stalling you need info from your car. Who knows maybe the fuel pump wiring needs correcting.

Do the compression test its fast and easy. Get a new CTS since your parts gun is out. Maybe change oil and check for fuel odors. Then look into getting your SES operating.

 

hmm didnt think of that. maybe i can at least get it to idle again and go from there. ill try that tomorrow.

 

Where are you from? How many miles on your Z? Btw welcome to TGO. Use the search button for searching past posts too

 

im from nevada, there could be 130k miles or 230k miles on it maybe even 330k but i doubt it. the big problem is its a california car and its got all the cali smog equipment making more parts expensive

 

If the odometer hasnt hit 100k the #'s line up perfectly. Once around slight misalignment, havent seen a speedo that went twice but id imagine itd be worse.

A good way to guess how many times it went around is looking for factory parts or lines. Rust isnt a goodway to determine, bc i picked up mine at 79k. But 2nd owner drove it in upstate NY and alot underneath has been rusted. The only way i know i have a BW rear is bc of the 9 bolts lol.

Post some pictures of the car, maybe the rig job for the fuel pump so someone can possibly help.

 

it does have a slight misalignment so it must be over 100k the coolant temp sensor is only 15 bucks i suppose i can try that but im just done dumping money into it

 

Have you done the common TPI Tune-up?

 

http://www.highperformancepontiac.co...a/viewall.html

for the IAC Valve, Pull back the spring and twist the coned needle all the way in. When you turn on the Camaro, the ECM will push out the cone to make the seal. If you have any questions, let me know. I have a GM Camaro Service manual and I will more than happy to post up a troubleshooting diagram for you. But the troubleshooting manual will only work if the Camaro is stock or nearly stock.

 

Very wrong. The CTS which is mounted on the intake manifold does absolutely nothing other then tell the ECM to fire its ninth injector if the coolant temp is below 90*. As for the fuel pump, whether the wiring is hacked or not, as long as it primes the fuel rail to 50lbs, and maintains its pressure to around 43lbs while at idle, then theres nothing to worry about. Now if there is a smell of gasoline in the engine bay, check the areas where there is a connection of the fuel lines. Some areas to check are where the High pressure hoses connect to the hardlines that are next to the AC Compressor, or where the high pressure hoses connect to the fuel rail. Keep in mind that there are also more than a few o-rings inside the fuel rail. So some of those could be dry rotted. Another place to check is the FPR. There also could be a leak on the injectors orings too.

 

All the rings that are colored blue or purple (im color blind) are o-rings.
They may be dry rotted, hence fuel odor in engine bay.

http://chevythunder.com/fuel_rail_as..._and_parts.gif