- This topic has 4 replies, 2 voices, and was last updated 7 years ago by
.
-
Topic
-
I have a 2001 Dodge Stratus as referenced. It is a 2.4 DOHC. For over a year now I have had a stalling issue when the weather gets warm. Initially I looked at the usual culprits: Vacuum leak, IAC, TPS, CPS. All have been replaced by myself and then a dealer for extra measure. Additionally I covered the basics of ignition coil replacement, spark plugs, air filter, ASD/fuel filter fuses. I was at my wits end until this summer when I decided to fully document a stall to hopefully gain more insight. I hooked up an OBD cable with accompanying software. Additionally I had at the ready equipment to test spark and fuel pressure. I went to a parking lot to force the condition and was successful, but as i attached the cable between the spark plug and spark plug cable something unusual happened. The car started right up. In the past the car would refuse to start for at least 30 minutes. As a further test I decided to leave the hood cracked. From that point on my stalling issue virtually disappeared. The only time it recurred was when I had my A/C going for about an hour. This was with the hood cracked and initially the car refused to start back up. The minute I opened the hood all the way the car started right up. I’ve come across a link via google that suggested an ECU might be susceptible to heat and starts to malfunction leading to a similar condition. Additionally I have considered the O2 sensor as a possibility. So far what I have learned is that when it does stall, the car will start for maybe a second, but refuse to keep going and then after a few tries it behaves as though it is either flooded or starved for fuel. To me this suggests that spark is present, but maybe fuel is an issue. Because of this I also thought about vapor lock. With the OBD attached I noticed that as it stalled the O2 sensor(bank 1 sensor 2) reported “open loop fault”. That’s the only thing I’ve seen. It seems clear that engine compartment temperature exacerbates the issue. I’m well over $1200 into this issue and would appreciate any ideas.
-
Replies
-
I’d take a close look at the Mass Air Flow sensor.
It would be very strange for an oxygen sensor to fail due to heat.
I’ve had MAF sensors fail and do exactly what your car is doing.
Sometimes just tapping on a bad MAF sensor causes it to go haywire.Here’s a link to diagnostics on it–note that the Stratus uses a Mitsubishi engine
http://easyautodiagnostics.com/mitsubishi/2.4L/maf-sensor-tests-1
Since you have a Snap On scan tool, you can watch the readings rather than test with a DMM.Link to testing the O2 sensor
http://easyautodiagnostics.com/mitsubishi/2.4L/how-to-test-the-oxygen-sensor-1After doing some research and frantic searching it appears that my car does not have a MAF, but it does have a MAP and an air temperature sensor. I have tested both and there appears to be no issues with them. One thing I have observed is that when the car stalls if I try to start the car by turn the key into the start position it will not start and exhibits symptoms of a lean condition, but if I turn the car completely off and then back on it starts right back up with no issue. Additionally once it starts like this it seems like the car is “reset” because it does not exhibit the problem unless I drive for an extended period of time(roughly 30 minutes) equivalent to the first time the issue arose. Any suggestions where to look? I have replaced the coil, spark plugs, and spark plug wires.
Thank you!
So there are no codes and you’ve covered the things that typically are suspect.
The ECU would certainly be next on my list.
Don’t see what else it could be.As an aside, the 2 door coupe definitely has both a MAF and a MAP.
Not sure if this also applies to the 4 door sedan.
Dodge and maybe even A1 Cardone, which remanufactures the MAFs could probably tell you.
- You must be logged in to reply to this topic.