OK, so i picked up a 1993 240 with 65,000 km and have had this lingering issue with stalling on start up with rough idle, and after it gets up in temp it will smooth out, but still has surging while driving when the pedal is pushed moderately. Every time I start it it will run rough and stall unless i apply the gas to keep it alive. I had a 1-1-3 code and has since gone after replacing the O2 sensor.


I have replaced plugs,wires,cap,rotor,TB serviced,new air and fuel filters,new injectors, also checked for vacuum leaks with my smoke machine and all seems fine. Any suggestions from here??

I have checked fuel pressure and its reading about 36-38 PSI after it smooths out, residual pressure was fine after 20 min above 20PSI. I also tested pressure from connector at the rear of the fuel pump (in tank pump) and was reading about 3-4 PSI

I dont want to go changing the pumps if its not necessary, any suggestions on where to go from here??

 

THere's a temperature sensor under the intake manifold that might be causing the problem or abit of it. CHeck this thread "Curious Cold Start Rough Idle Problem" I have a pm to both these guys but I am waiting on a response. As I have something similiar. Please let me know what happens.