Ok, I am working on a car for some people. It is a 98' 4 door cavalier with the 2.4l auto in it. We are changing the motor for them because they wanted a newer motor in it. No service engine soon light on before we started this. We put a 99' 2.4l motor in it out of a grand am. The service engine soon light came on. We reset it and it came on again. The only thing we used off of the old motor was the throttle body and intake. I can't remember the exact code but it was something with the egr valve. Insufficient flow or something like that. So we changed the egr valve and it came on again after driving it for a few minutes. So we put the old motor back in and now we have the same thing happening. I NEED HELP!!! It is driving me nuts. Does anyone know what we could of done that is making it do this???

By the way, I did all the searching on the egr valve, so I know to clean it and what everyone else has said. I was just wondering if there may be something else that could be causing this.

Thanks again,

Jim

Knowing the exact code would help. There's probably nothing wrong with the new motor, probably just a connector or something lose.

I used to work at a dealership, not independant shop.

Most of the time an insufficent code for EGR, wasnt the EGR, but the passges going to it or from it.

The EGR is monitored for flow, if the passage clogs up, there is no flow.


- 2004 Cavalier - 124k, owned since new

DTC P0401 Exhaust Gas Recirculation (EGR) Flow Insufficient This was the code we kept getting.

Would I be able to use an air compressor to clean out these passages or do I need to spray something in them first?

I could only assume that having a cavie's ECU controlling a Grand Am's engine would have something to do with it.

We put the old motor back in though and are getting the same code.

We now have cleaned the passages, different gaskets, changed egr valves again, and the damn thing still comes on. Anyone have any other ideas?? I am ready to shoot the little light out..lol