89 350 TPI Starting Problem

[badata1]

Hello Everyone. I just joined this forum and was hoping for a little help...

I have a 89 Trans Am GTA 350 Automatic 700r4

It has been rebuilt:
Bored .30 Over
Edelbrock Aluminum Heads
Thermomaster Computer Chip
Mild Cam
1.52 Roller Tip Rockers
Headers
Hi Flow Runners
Holley Throttle Body
and some other minor upgrades

Heres my problem... It starts everytime cold with no problem.
But after it runs for just a little bit and i cut it off it doesn't want to start back.
- It doen't overheat
- I have replaced i believe EVERY sensor on the car lol (including ignition module and coil)
- It is getting spark... (i'm pretty sure the injectors are spraying at the wrong time)
- The engine light is not on
- There is 55 psi at the fuel rail
- The only way to get it to start is to put a little starting fluid in it... and then it will start and run fine (idles a little rough, could be the cam? or connected to the starting problem)

Any help is greatly appreciated i've been trying to figure this out for about 6months now and am desprate.
Thanks in advance.. and if any more information is needed i will gladly tell all i know.

[mtperformance]

Why are your injectors out of time

[badata1]

ok... found out the injectors arn't spraying at all... so i checked the resistance on all the injectors and there fine... so i guess i'll try replacing the computer? I believe thats what tells the injectors to fire.. but not positive

[five7kid]

Sounds like something electrical getting hot.

First thing I'd do is put the stock chip back in and try it that way.

[Zero4488]

I have an 86 TA TPI, and when my computer started to go, the car didn't wanna start, it didn't wanna run, it would turn off while driving it....just be careful, I don't want you to get stuck with a fried computer like I did....

[DeMasi1990]

My 90 TPI Trans am Is running extremely Rough, I replaced the computer and it did abolutley nothing..I have a feeling my chip is bad, Im not sure..I checked the resistance of My fuel Injectors too and they checked out, I just cant figure out what it is at all, Ive also replaced most of the sensors aswell..I guess my mechanic was right, TPI's are fussy

[Zero4488]

Don't get that way yet...it could be a number of things, check all your hoses for vacuum leaks, TPI's dislike vacuum leaks, also check you coil, cap, rotor, plugs (if you can), and check your spark plug wires, TPI's have an awful habit of dropping the plug wires on the headers, also another problem I found, is check that your O2 sensor wire is not melted to the header....those are a few of the many everyday problem I have to deal with....just give everything a quick once over and see if it's any of the following....

[joejoe]

mine did the same with the no/start when warm, it ended up being the Coolant Temp. Sensor (in the pass. side head in front) all it is for is to tell the ECM what temp. the coolant is at.

[Red Devil]

The CTS typically will make the car run really rich all the time.

Badata, hate to ask, but are you sure the injectors aren't firing? If so, I'd check the wiring.

It's batch fire and the computer does have the drivers in it, but all they do is actually ground the injectors.

What I would do is check the wires at the harness for continuity against the block. If you do, you have a pinched wire somewhere (valvecovers seem to love grabbing that harness). To check to see if you are getting the firing signal go get a noid light and check.

[joejoe]

[quote=Red Devil;94900]The CTS typically will make the car run really rich all the time.

And that 55lbs of fuel pressure wont help ether.

Have you checked the pick up coil in the dis. it could be getting hot and not working, until cooled down.

good luck