When this has occured, the check light was on, because I had a bad O2 sensor. Suddenly, as I tried to put the pedal to the metal, the engine died after what seems to be a backfire.

Since then : It runs at idle roughly, but can't rev more than 1500 rpm.

Since I have another 89 in my bacyard (working), this is what I've done :

-replaced ECM Unit
-replaced coil
-new spark plugs
-disconnect exhaust befor catalytic converter to check if it was not damaged, the problem is the same
-change every sensor under the hood
-replaced both fuel nozzles
-the fuel is okay
-ignition okay

So what should I do now ???

 

Three things I would check would be TPS if it's the DFI and vacuum advance if carb.and then pick-up coil in distributor.

 

Thanks CadsForFun, I have tried these things, but it doens't fix my problem...
It s DFI (2 nozzles).
I have replaced the rotor, distributor cap too..
How should I know from the on board computer ? First af all I would like to reset the defaults codes...

 

Have you pulled the codes already and what were they?? Clear them by entering the diagnostics, pushing and holding off and hi until oo appears then 70 will appear. Now you can see which codes come back when you run the car. Post them so we can go from there.

 

The only code I got were e052 ans b552.
But at last I have found that the catalytic converter was totally clogged!!!
Thank you for your help, I hope my reply will help some people...