I've just changed the ECU in my MY00 turbo, from an AE802 to an AE801, and all of a sudden, when warm the idle speed is all over the place.

it's jumping up and down from 1000-400rpm, and starting to feel like it's going to stall, although it's only stalled once so far.

So, is this a failing MAF or is the ECU still trying to figure out where the hell it is?

The AE801 ECU has been in the car since monday night, and i've done around 20-30 miles in it since then.

It was fine with the AE802 in it, the idle was linear, and set around 750-1000rpm.

Help!

 

MAF.

By removing the ECU you've reset the learning that it had, to cope with a damaged MAF. Now youve put a different one, its revealing the dead MAF. To make sure, reset the one you have in now. And drive off boost til you get a new one.

Unplug the MAF at idle and see what it does.

MB

 

Try refitting the AE802. If it is still rubbish then your ECU had probably adapted the idle around the failing MAF.

You've uncovered a failing MAF most likely, happens quite a lot.

 

got there first

MB

 

I thought as much, thanks guys.

Where is the MAF plug on a 2000 model?

there are far too many plugs in that area and i'm reluctant to unplug the wrong thing!

Any idea how much a new MAF sensor is?

 

New sensor is about £80 from dealer, or Xtreme scoobies etc.

Sensor lives in the cylindrical plastic tube down from the airbox. Plug sticks out the side.

MB

 

It's all sorted now, the car is booked in for a service with Subaru-4-You this weekend, and having just phoned Len, he's going to sort it out for me then.

Thanks guys, much appreciated!