I have just had the car serviced, after a motorway run or when I have given it some, the car starts to hunt from normal to 1000 rpm. When it was in for a service I had it checked for any codes and none were found. I have red on here that it sounds like the MAF is on the way out, so could be this. I also had an uprated fuel pump and fuel pressure regulator fitted (FSE 1:1), could it be that the fuel pressure is not high enough, I would check but can't remember what pressure this needs to be set at.

Any help or comments would be great.

simb

 

Bttt

 

Hi ya,

Mine's (MY99 Type RA STi) been suffering from this since I've had it (exactly the same, only after a cruise along the motor or after having given it some). I'd already changed the MAF (which woz defo gone anyway, lit up the KL like a xmas tree) but the fault still remained.

I've just changed the Lambda and all is well.

She had also been running very lumpy in the 2,000 - 3,5000 rpm range.

 

Same sort of symptons as mine, but its not running lumpy, its running sweet at the moment.

simb

 

Fuel pressure should be about 3bar or slightly more.

Sounds like a dodgy MAF to me also but if you have a volt meter it might be worth checking your lambda readings at the ecu:

Connector B136 Pin 21 IIRC.
Should read about 0.8v WOT (when mine was duff it stayed at 0.2v whatever throttle position)

 

Cheers, will adjust it tommorow and see if it sorts the dodgy idle.

simb

 

Earthing could be an issue - maybe a cheap fix if you DIY it, and at least your audio should improve

 

When I had exactly these symptoms on TWO MR2s that I owned a few years back, they both turned out to be the head gasket on its way out.

 

Just had mine in for some work yesterday (new gearbox).

Got it back last night, and now it seems completley confused.

Goes up through the revs far faster than it used to. Stop accelerating and drop the clutch and the revs drop to zero. Its stalled on me twice now in less than a day. It's also hunting at idle.

Sounds like another MAF bites the dust.

Getting new one tomorrow, should hopefully fix the problem.

I've heard that you should lay off the turbo with a dodgy MAF. Is this true?

Chris

 

Yes, most definitely.

 

I've increased the pressure on the regulator and it seems to have done the trick...for now anyway, will have to keep an eye on it.
Cheers peeps for your comments.

simb