Hey Guys!
My 2005 GP has 202k miles and has been having an issue stalling when first starting, the rpm's start out low and sometimes it will barely recover and stabilize on its own but 90% of the time I need to gas it for a brief moment while cranking to keep it from stalling. Once it tach’s up and falls back to the Idle speed it is stable with only minor fluctuation of RPMS. It only stalls at startup so I am guessing it is getting out of range readings from a sensor or has there is something causing the idle to When the issue first appeared it was in the winter and a scan suggested a faulty Thermostat or Engine Temperature sensor. At that time the MIL was intermittent.. then the MIL started to become constant and those codes disappeared the CODEs were for EVAP purge valve ( P0443 ) and MAF ( P0102 ) and EGR valve. I replaced the EGR, MAF and EVAP Purge Valve. The EGR code disappeared, but the P0102 & P0443 are still there.
I have also noticed some of following symptoms:
1) When coming to a stop the “Charging System Failure” DIC is displayed for about 2 seconds right after stopping even after replacing the battery and the Alternator.
2) The engine appears to run hotter than expected and there seems to be excessive air in the Heater core after a heater core replacement even after a mechanic attempted to bleed the air
3) There is a slight reduction in fuel economy since the MIL started lighting (at least 2-3 mpg lost with mixed driving)
4) The Air Conditioner stopped working sometime between last time it was used last fall and first time it was used this past spring ( but when a mechanic checked the refrigerant level it appeared normal pressure range )
5) Slight ticking noise in the engine compartment but hard to tell if it is a lifter or valve or coil pack or fuel injector since I can’t seem to pin down where it is originating
6) I noticed the headlights do dim slightly if I try to put the windows up when they are already up.
7) I also noticed that prior to replacing the battery, the vehicle was not starting easily even when jumping with a vehicle with a good battery and after cleaning and tightening the battery terminals .. this makes me think there is possibly a bad ground at the chassis or at the Starter?
The maintenance I have performed recently:
1) oil change
2) New Plugs
3) New wires,
4) New PCV valve
5) New Alternator
6) New battery
7) New EVAP Purge Valve
8) New MAF
9) Cleaned and added dialectric grease on MAF and EVAP valve connector terminals
For the Charging System Failure, the low idle / stalling at startup and the MAF code I am guessing it could all be caused be a bad ground causing a low supply voltage to the sensors???. I am going to check the main ground and check voltage at the sensors. I am also going to look for vacuum leaks tonight. Is there anything else I should look for? I am guessing I should also check for a restricted exhaust / Catalytic convertor and also check for exhaust leaks before the O2 sensors. The exhaust leaks were hard to check till today because the Resonator had a 10 inch long hole in it at the seam.
