Hello!

I'm restoring a 1990 RS 5.0 and unfortunately since i have it, the car stall and dies when warming up...
I've looked all the forums and video but nothing works!
I've already changed :
Fuel pump, gasoline filters, spark plugs, ignition distributor arm, ignition head, spark plug wire, ignition coil, rebuilt kit throttle body, IAT sensor, TPS sensor, thermostat, ignition control module, oil temp sensor, oil pressure sensor, motor temp sensor, O2 sensor.
Yes that's a long list and i probably miss some components! But still stall and dies...

PLEASE I NEED HELP.

 

It's rough trying to fool with 80's and 90's American cars in Europe with getting parts and finding mechanics to work on them.

 

Oh sure it is...
I mainly bought all my parts from rockauto

 

Stick or auto? Tbi or tpi?

 

my bad, auto tbi

 

Okay so I’ll assume the car runs well when warmed up, so let’s start with the obvious, you need air fuel and spark and as long as the valves and pistons aren’t leaking sealing it will run.
Being auto there is one other thing to look out for and that’s the lockup converter, they can sometimes lock when at idle dragging the engine and stalling it.
I also remember an issue with some of the older gm ecu’s the solder would crack and cause all kinds of crazy issues.
I would start with
1. Check to see if your losing ignition, easy all you need is a timing light.
2. Check see if your losing fuel, pull the air cleaner and have a can of ether/starter fluid ready and spray while it’s trying to stall.
3. If your not losing fuel or spark unbolt the torque converter and retest.

 

I thought i already said it but the car runs well when cold (a bit too high in rpm) and when warming up (like 4 min) , it slowly decrease in rpm and stall then dies, all of it when in park.

 

Okay so when it’s at operating temperature it won’t stay running?
All three that I mentioned still apply.

 

That's right.
I'm going to buy a timing light to test but i don't think there will be issues on that part.
For the fuel, everything is ok.
And i suppose that the torque converter should not be engaged while in park?

 

Correct, a bad converter usually only stalls the car when in gear but I did once have a car at the shop with a stalling issue because of it even in park.