Syztemlord

Hi Guys. I've got a MY99 Turbo which has been left standing for 2 years. I recently got it back and I have a problem. Shortly after driving, when I pull up to the lights or stop, the revs drop down to about 100rpm then jump up to 1000rpm. It keeps doing this until I pull away.

Also when I go above 4000rpm the car starts to hesitate and jump badly. I've reset my ECU which showed no problems, and its had a full service.

Any ideas?

WRXshaneWRX

iTrader: (1)

could also be ur coil packs mate, if you have them or plugs

RB5Caterham

When the car is at idle, unplug the MAF.

If the car stalls then the MAF is at fault. Might also be the Lambda/O2 Sensor.

Perhaps even a dirty boost solenoid, especially as you say the car hesitates when on boost.

Syztemlord

Ok, I'll try that a bit later and let you know the results.

vindaloo

With a known good MAF, unplugging it should cause the car to stall. I think you've got it backwards.

Unfortunately, sorting these sorts of problems out needs to start at one end and work down the system. No point in trying to assess the health of the Lambda if the MAF is knackered etc...

Quickest way to get a good indication is to take the car to a local specialist and get them to diagnose it. Might cost a few ££s (leading to maybe £££s) but it's the quickest way.

J.

RB5Caterham

I stand corrected, thanks J.

In fairness he's asking what might cause those problems, I'm not saying its all of the above but they tend to be the common ones.

Going to a specialist is like you say a quick but expensive way to sort a problem but I suppose this is the idea of forums like this, where people can say what they have done to resolve similar problems going on their\mates experiences.

You could go to a specialist for every problem, where would places like this be then?

Sorry I'm not having a go or anything.

Syztemlord

Thanks for all the input, I would go to a specialist but I don't have the £££ let alone the ££! LOL

Ok, I unplugged the MAF while running the engine and the revs dipped right down to the point of stalling but then picked up and ran steady.

I reset my ECU this morning and have noticed a slight improvment when putting my foot down. The car still jumps a bit at mid/high revs but not as bad as before. The idling problem is still there though.

ReggieMY99

The engine should stall when unplugging the maf, replace the maf before you damage your engine

RB5Caterham

As Vindaloo and ReggieMY99 says your engine should have stalled if the MAF was OK.

You should really do the test after the car has been driven for a while rather than leave it running from cold and then testing.

Have you done an ECU check?

Instructions here.

JollyGreenMonster.co.uk

Syztemlord

I did the ECU check yesterday and everything came back normal. I've now ordered a new MAF, should arrive soon. I'll post back with the results, fingers crossed!

Oh and Happy christmas to everyone!

Jolly Green Monster

iTrader: (4)

symphtoms do sound like MAF.. however if is has been standard for 2years have you done the basic checks? replace the plugs as they are likely to be well corroded, change the oil etc.. a basic service.. if it didn't run for two years I would consider the cambelt too..

Simon

Brun

Until this issue is sorted - the last thing i would be doing is booting it. If it is the maf - there is the potential for ending the life of your engine

Syztemlord

Just did another ECU error check and it came back with the MAF 23 error, good job I've just ordered one! I'm driving it very slowly at the moment and not booting it anywhere, although thats not a problem as I live in Guernsey where the speed limit is 35! LOL