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check engine light, irregular pattern

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Car is a 98 GT so it has the 2.5 DOHC motor. Have had a bunch of work done recently and am getting check engine light but it comes and goes off with no set pattern. Had head gaskets done a month ago after which car developed poor idel, stalled at a light.

Dealer says it's the idle sensor so we change that, runs fine for 2 days then problem comes back and light goes on again. Car won't start one morning so trace that to bad battery connection and to be safe replace the battery.

In the worst case car stalls once warms up, about 20 miles, then when I restart it I have aterrible misfire, low power etc. Stop the car wait a minute fires back up and all is fine but still have the check engine lights. Leave it sitting for two days and when I start it no check engine light, runs fine for 50 miles then it's on again. Have even had it go out after car has sat for 10 minutes. Can't find a common condition to trace it to.

Was there a recall from Subaru on the Mass Airflow Sensor on these cars? thought I heard that but of course the dealer never mentioned it when I had the head gaskets done. I did get a free alternator though on recall.

If anybody out there has seen this please tell me where to start loking please. Winter is coming and I hate being stranded in the cold.

 

Thanks,

 

Glenn

Vermont

  • 3 weeks later...
  • Author

for anyone checking this posting here is the solution. Bad ground on main fuse box was causing the problem. Pulled the fuse box cleaned up the contacts and ran an extra ground wire off the battery terminal. That solved all the issues created by the bad ground causing the ECU to get erratic readings.

 

 

Glenn

 

Car is a 98 GT so it has the 2.5 DOHC motor. Have had a bunch of work done recently and am getting check engine light but it comes and goes off with no set pattern. Had head gaskets done a month ago after which car developed poor idel, stalled at a light.

Dealer says it's the idle sensor so we change that, runs fine for 2 days then problem comes back and light goes on again. Car won't start one morning so trace that to bad battery connection and to be safe replace the battery.

In the worst case car stalls once warms up, about 20 miles, then when I restart it I have aterrible misfire, low power etc. Stop the car wait a minute fires back up and all is fine but still have the check engine lights. Leave it sitting for two days and when I start it no check engine light, runs fine for 50 miles then it's on again. Have even had it go out after car has sat for 10 minutes. Can't find a common condition to trace it to.

Was there a recall from Subaru on the Mass Airflow Sensor on these cars? thought I heard that but of course the dealer never mentioned it when I had the head gaskets done. I did get a free alternator though on recall.

If anybody out there has seen this please tell me where to start loking please. Winter is coming and I hate being stranded in the cold.

 

Thanks,

 

Glenn

Vermont

  • 1 month later...

Great tip. Had same problem with IAC code as well as VSS 2 code. Replaced both and still got intermittent light. Cleaned ground wires from the battery. No CEL in 6 days, runs great. Thanks

for anyone checking this posting here is the solution. Bad ground on main fuse box was causing the problem. Pulled the fuse box cleaned up the contacts and ran an extra ground wire off the battery terminal. That solved all the issues created by the bad ground causing the ECU to get erratic readings.

Glenn

Could you be more specific? Are you talking about the fuse box in the engine compartment? Where is that ground connection placed? Under the box? Part of the box? And you ran your extra ground wire from the battery to where?

Thanks in advance!

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