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Calling all "Car People!" Help!
10 years ago
I have a weird issue with my vehicle, and it's not worth the trouble of taking it to a shop to let those witch doctors pressure me into basically rebuilding the entire car to probably not even fix it.
2000 Malibu with a p0442 EVAP code
Here's the history with the problem:
Runs poorly intermittently for a few years now. Some days it's fine, some days it just has a big power loss and hesitates on acceleration. Hasn't gotten 'worse' but no repairs make a difference for better or worse.
- ODB code for the EGR is on. Replaced that, the old EGR had a bad solenoid. Code resolved but now p0442 comes on.
-Replaced gas cap, reset code. p0442 came back and no change.
The symptoms:
-Car runs great on a full tank of gas. It gets to 1/2 full or less and runs noticeably worse. Rougher starting and idling, and seems to lose power and refuse to accelerate more noticeably.
-Car loses power, almost feeling like it'll stall, when driving into strong winds.
Where do I even start in pinpointing the likely sources of these issues?
Extra info: has new plugs & wires and a new fuel filter. Routine maintenance.
2000 Malibu with a p0442 EVAP code
Here's the history with the problem:
Runs poorly intermittently for a few years now. Some days it's fine, some days it just has a big power loss and hesitates on acceleration. Hasn't gotten 'worse' but no repairs make a difference for better or worse.
- ODB code for the EGR is on. Replaced that, the old EGR had a bad solenoid. Code resolved but now p0442 comes on.
-Replaced gas cap, reset code. p0442 came back and no change.
The symptoms:
-Car runs great on a full tank of gas. It gets to 1/2 full or less and runs noticeably worse. Rougher starting and idling, and seems to lose power and refuse to accelerate more noticeably.
-Car loses power, almost feeling like it'll stall, when driving into strong winds.
Where do I even start in pinpointing the likely sources of these issues?
Extra info: has new plugs & wires and a new fuel filter. Routine maintenance.
A non-conforming gas cap (i.e. not factory/original brand)
A small leak/hole in a fuel vapor hose/tube
Other small leak in EVAP system
Faulty vent o-ring seal
Defective vent valve
Defective purge valve
Defective leak detection pump
On the plus side, it's been ongoing quite a while so I'm not worried it'll suddenly die. : \
Also, I'm pretty sure there are multiple things going on. Vapor leak being one.. I had been talking to a friend and the acceleration/stalling issue sounded similar to a problem he had. Turned out the hose was brittle and damaged making a shoddy connection at the MAP sensor. I'm considering replacing the O2 sensors and having the MAP looked at.
For pressure lines, you need a ultrasonic probe, which, is out of your range of backyard troubleshooting.