Greetings all,
I am having a bizarre issue on the 3.5 of my 280se pertaining to start up
So for cold starts the car will crank over and fire up pretty quickly, however once it's running it needs throttle applied to keep the revs up near 1000 to stay running. If not helping with the accelerator the rpms will stall out until it dies. Then to get it to fire back up you need to hold the accelerator to the floor. This is the same case on warm starts, the car will just crank for days unless you hold the accelerator wide open. After driving for a while or just after trying to restart after the first cold start. When it's actually running/ driving the car runs great, has good power and has no issues. Though sometimes it will randomly stall out when coming to a light.
I have tested fuel pressure and it is within spec, Originally it was a bit high, lowering it helped the car start a bit better.
TPS is tested working. MPS has been tested and the ohms are within spec. Temp sensor 1, coolant temp sensor is a bit out of range, but not sure it could be the culprit here. I have pulled injector rail and see them spraying. New spark plugs, cap/rotor were last done in 2016 I believe, with next to no miles since. Replaced coil resistors. New battery, rebuilt alternator. Ive jumped the CSV through the ECU and it does open up and spray into the system.
I am kind of at a loss with this issue, it is very bizarre, Ive never had a car that needed an accelerator matted to start. To me this implies the car needs that additional air from an open throttle body to start? Implying perhaps the Aux air valve is not funneling in the air properly? Or its flooding itself of fuel and air is clearing it out?
CSV perhaps being stuck open? Causing the right fuel for a cold start but too much once running?
Any help here is appreciated. Thanks!
