I took my '99 Outback into the shop because the check engine light was on. The codes are related to O2 sensor and vehicle speed sensor problems.

 

The say that they found some service bulletins that indicate the PCMs on these cars are known to go bad.

 

Is this true? Is it something Subaru may replace without charge? Would a bad Power Control Module cause the errors that I mention above?

 

Thanks!

Never heard of a "PCM" going bad on a Subaru. Heard plenty of things about O2 sensors and VSS (speed senors) going bad though.

Never heard of a "PCM" going bad on a Subaru. Heard plenty of things about O2 sensors and VSS (speed senors) going bad though.

 

I have seen them go bad, when they go bad they won't comunicate to scan tools either. The fact that you are getting codes shows you have a good ecu.

 

What were the exact codes and corresponding numbers?

The engine control unit can have internal problems just like anything else on the car. They are normally very reliable and usually the last thing to suspect for trouble, unless some sort of major electrical surge has happened. A good shop shouldn't have to guess if a sensor or the ECU (PCM) is bad. Using the proper test gear and test procedures will tell them if the problem is with the sensor or the ECU. If your current shop is guessing at the condition of these things you should find a better shop.

I have seen them go bad, when they go bad they won't comunicate to scan tools either. The fact that you are getting codes shows you have a good ecu.

 

What were the exact codes and corresponding numbers?

 

The codes are:

P0130

P0136

P0500

P1100

P1101

P1120

P1121

P1540

 

More comments regarding them are in these two threads:

http://www.ultimatesubaru.org/forum/showthread.php?t=77861

http://www.ultimatesubaru.org/forum/showthread.php?t=77863

 

Thanks.

I bet there's one or two broken sensors that are causing all those other codes to be thrown.