misfire, ignition, MAF sensor?
barossu19
09-24-2016, 02:13 PM
2005 Impala LS 3.8
115,000 miles
Yesterday after stopping at a store the car would not start for my wife. I told her to wait for a few minutes and try again,...no luck. Called AAA, an hour later he arrived and the car started and ran fine. No codes at this time.
This morning I started it and it idled normally for about 5 minutes then started misfiring and died. I started it again and it would run as long as I kept it at 2000rpm with intermittent misses. It finally shot the codes, p0350 and p1350. I bought the three new coils and installed but this did not solve the problem. I then suspected the ignition control module but was reluctant to buy another $150 part without knowing for sure, so I played around a bit. I discovered that when I unplug the MAF sensor the car runs perfectly fine and when I plug it back in it goes back to the same problem.
Can anyone enlighten me to what might be the true source of the problem?
Thank You!
115,000 miles
Yesterday after stopping at a store the car would not start for my wife. I told her to wait for a few minutes and try again,...no luck. Called AAA, an hour later he arrived and the car started and ran fine. No codes at this time.
This morning I started it and it idled normally for about 5 minutes then started misfiring and died. I started it again and it would run as long as I kept it at 2000rpm with intermittent misses. It finally shot the codes, p0350 and p1350. I bought the three new coils and installed but this did not solve the problem. I then suspected the ignition control module but was reluctant to buy another $150 part without knowing for sure, so I played around a bit. I discovered that when I unplug the MAF sensor the car runs perfectly fine and when I plug it back in it goes back to the same problem.
Can anyone enlighten me to what might be the true source of the problem?
Thank You!
maxwedge
09-24-2016, 03:16 PM
If you Google p0350 code there are several diagnostic trees available.
j cAT
10-01-2016, 07:33 PM
when an engine does not start and you have spark and fuel disconnecting the MAF is a test to determine if the MAF is the problem.
maf has temp and air flow sensors these can cause no start.
some stores if the MAF does not fix it take it back.
another item is the ECT usually the connector to it gets damaged or the wiring then the PCM provides improper injector operation.
with the codes you have the ICM and coils are replaced as a set. bad coil can kill the ICM. ICM and coils work together.
why it runs good with MAF disconnected I don't understand . codes say ICM and coils. could be wiring to them. follow instructions on the ICM replacing .
maf has temp and air flow sensors these can cause no start.
some stores if the MAF does not fix it take it back.
another item is the ECT usually the connector to it gets damaged or the wiring then the PCM provides improper injector operation.
with the codes you have the ICM and coils are replaced as a set. bad coil can kill the ICM. ICM and coils work together.
why it runs good with MAF disconnected I don't understand . codes say ICM and coils. could be wiring to them. follow instructions on the ICM replacing .
barossu19
10-02-2016, 04:02 PM
Problem Solved...I checked the voltage of the MAF. Before ignition it was 2.5v. I started it and the voltage stayed steady for a few seconds then started jumping all over the place...simultaneously the engine started spitting and sputtering. I installed a new MAF and it has been running perfectly for a week now.
In the end I think that I had a bad coil AND MAF at the same time but I was trying to diagnose the problem as one issue.
In the end I think that I had a bad coil AND MAF at the same time but I was trying to diagnose the problem as one issue.
j cAT
10-02-2016, 06:32 PM
Problem Solved...I checked the voltage of the MAF. Before ignition it was 2.5v. I started it and the voltage stayed steady for a few seconds then started jumping all over the place...simultaneously the engine started spitting and sputtering. I installed a new MAF and it has been running perfectly for a week now.
In the end I think that I had a bad coil AND MAF at the same time but I was trying to diagnose the problem as one issue.
good you fixed it . with the 2 problems its a PITA ... you did the fix pretty good.
a bad coil as I said can mess up the ICM. the ICM can be tested call the auto parts stores like autozone or o'rielly...ICM can be intermittent on failures .. .
In the end I think that I had a bad coil AND MAF at the same time but I was trying to diagnose the problem as one issue.
good you fixed it . with the 2 problems its a PITA ... you did the fix pretty good.
a bad coil as I said can mess up the ICM. the ICM can be tested call the auto parts stores like autozone or o'rielly...ICM can be intermittent on failures .. .
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