Hey guys long time fan of the site, I have a 86 TPI that has been my baby for 4 years but now is having trouble on cold starts. Either she will crank for about 5 secs before firing or just sounds like crap. Once she gets started and runs for a little while she will restart like the champ she is.

Fuel pump is not the problem and I really feel like Ive narrowed it down but I cant find a cold start valve anywhere!! The question is has anyone reprogrammed there ECM so it uses all 8 injectors to start??? Is this difficult to do by yourself??

Thanks

 

The problem might be the fuel pump relay. It juices the pump until oil pressure presuure builds and then the fuel pump will run even if the relay is bad. It will restart when warm because the fuel rail is still pressureized.

 

86 -89 use the same '165 computer
Get a prom ( chip ) from a similar spec '89 car or get a custom chip programmed with the '89 tune.
'89 was first year the injectors programmed for cold starts and the CSI deleted

May not be the CS injector itself faulty but the cold start switch that controls it ( still very expensive.)

When cold check to see if you have 12V out of the CS switch at front of intake to the CSI when cranking (only )
Check to see if you have 12V going to the CS switch when cranking ( only )

 

replaced relay, still same deal, in fact if anything Im noticing a rougher idle

will check the volts on the CS tomorrow morn