To start with i bought the car 87' V6 MPFI bought a wrecked 92' RS 305 TBI. Put 1.94 heads on it with carb edelbrock intake. New roller fuel injection cam. Got my tax money back bought a tpi setup off of ebay it came form an 86' and came with a Painless wiring harness(PainFULL). It will not start unless ive got wide open throttle then it will start firing everyonce in a while.

First it wouldn't start because the regulator was bad. Fuel was leaking past the diaphram and in the vacuum hose to the plenum. Rebuilt the regulator. Got it started once for probably 15 seconds. The it got worse and worse until it just would even sound like it was gettin fire. Took the ignition module out and it tested good.

So I pull the fuel rails and turn the car over. One side spits on doesnt. Long story short 5 good injectors 3 bad. Buy 3 remanufactured injectors. Still doesnt start

I got it started again with the throttle being wide open. Wouldn't run for any length of time unless I hold the throttle down. I pulled the codes after I had it running the last time(probably 20 sec. the longest time). It came up with 12(normal) 15(low coolant temp(never had it running long enough)) 22 (WOT I had to start it somehow) 34(mass air sensor being too low out of range or something like that) and 42(electronic spark timing circuit).

Painless book said the electronic spark control module is only for certain applications. Autozone said mine is that application. Get it hoping it will start right up now... NOPE still no.

I don't have an oil pressure switch does anyone know whether the circuit is supposed to be open or closed to run???

Also note my fuel pump is just wired to try to get it started it is not wired through a relay or even through the computer. Does the fuel pump have to be wired through the computer?? My park neutral switch is bypassed. I do not have VATS components of any kind.

It confuses me because I've had it running just not for very long and it didn't run good at all... Rich black smoke that smelt like straight gas. After the last time I had it running I felt the headers and the three rear cylinders on the passenger side were warm enough it'd probably burn you. the other one on that side was slightly warm and the other four were cold. I've pulled the dist. 50 thousand times and thought it was 180 out and moved it a tooth here and there. and then I'd line the timing mark up and start from scratch... I'm thourghly pissed off with it and I can't go another week without my car... I'm about to put my carb back on...

Please anyone out there that might beable to help please don't hesitate to respone... Thanks in advance..

 

I know exactly what you are going through. My 91 Forumla would not start after I rebuilt the engine and swapped to tpi. It would pop and try to start only if I kept the throttle wide open. I too checked the ign timing about 50 times to make sure I wasn't off. I replaced dist, coil, injectors, map sensor, to no avail. I finally found out that my cam timing was way off but I found out to late, with all the cranking I washed the cylinders down with fuel and washed all the oil off of the pistons thus allowing them to stick and seize. I had to pull it out again to get them freed up and rehoned the cylinders and as of tonight I just got the engine sitting back in the car.

 

I had the car going with a carb so why would the cam timing not work with TPI since the cam is a fuel injection cam anyways. I don't know the exact specs and I dont know how exactly cam timing works so I guess it looks like I'm back to carbureted, for now. Anyone else have any insight or might be willing to explain to me how to fix the problem please write back I still want to go TPI sometime soon...

 

I didn't relize that you had it running with a carb. What was your fuel pressure, did you check to see if you have both fuses in for the injectors, are all injectors opening. Sounds like an injector problem to me.

 

What computer chip are you running?

I could not get my TPI running either at first. I did a little research and concluded that I had the wrong chip. I have the 87 TPI with 9th injector and my chip was setup for the 89 TPI with out the 9th injector. As soon as I swapped the chip out I was able to get her running.

I am also using the painless wiring harness. I thought it was rather easy to set up, especially since I was swapping my L69 computer carb for the TPI.

The fuel pump will not operate if the oil pressure switch is not closed. This prevents the fuel pump from running when the engine does not have oil pressure.

Any way, check your chip out and see if you have the right one for your application.

 

I was told that all my stuff came off the same car so the computer should be an 86' like the intake and everthing else. Where are the fuses for the injectors at??? in the computer itself? I need to rewire my whole car, it is a mess. I know I have had gas coming out of the injectors because I have had it running just wouldn't run for crap.

The painless harness wasn't that bad it's just the fact I wish they would make them app. specific or do something else. I had probably 6-7 ugly plugs left over that I didnt use just hangin there gettin in the way and bein ugly. Also, if they're going to divide the harness in sections then MARK them. As far as I'm concerned they should have done like my factory V6 harness was and have a main plug that mounts on the firewall that seperates the harness in two pieces.