Amstrad2000

I've had this problem with mine for quite a while, it doesn't happen all the time but often as I'm approaching t junctions and dip the clutch the revs drop, it judders and then returns to 1000 rpm tick over.

I was testing this the other day in my driveway and I found if I hold it at 1500 rpm and then slowly lift my foot off the throttle the revs keep going down and down until the engine cuts out. It's never been a problem on the road though so I've not got it sorted out.

Ads2k

I had this on mine also . Dealer said nothing wrong.

However it's completely vanished since having the map sensor replaced under warrenty.

Maybe just a bit of luck but the cars running a lot better since having it fitted.

Hope this helps guys.

Sundance

What problem did you have that led to your map sensor being replaced?

Cheers,

Ash

mikey k

You can do the headlamp washer yourself just pull the fuse under the bonnet!
My centers were replaced last month, just before I put the Volks on

MB

The MAP sensor being faulty WILL cause this.

The MAP effectively tells the ECU what air flow its seeing and the ECU calculates this into an engine load. When these things start to fail (sensor gets dirty) they can read low and mess up the idle - and even worse, lean the mixture out on VTEC.

Seen many a scoob go pop from this. Replacing mine next week after I check the price! Think they're $80 from the states plus tax etc...

Other possible ones are air leaks, ISCV, or your lambda sensor being shot (most likely behind MAP)

MB

MB

PS - having the engine replaced involves battery off so the ECU loses its learning. When these sensors start to fail the ECU tries to learn its way around the problem, and can do to a point.

When you reset the ECU you will go back to square 1 and the idle may be bad again til it learns its way round it.

If I had an engine failure id be taking a good look at the calibration of this wee beastie

MB

mikey k

Reckon I shall be having mine off to inspect it!

Sundance

Interesting....

Incidentally, about 3 hours before the shudder happened, I had reset my ECU. And about 1 hour before that I disconnected/reconnected the MAP sensor lead.

When I tried the car again today all seems to be normal....? maybe the ECU was still in a 'learning' stage when I experienced the problem...?

I'll keep an eye on it and see if it returns.

LLOYDJ

http://marketplace.s2ki.com/s2ki/product.p...18&cat=7&page=1

See above for new MAP sensor!

Fitted a new one to mine an cured stalling problem!

MB

You'd be amazed at the crap on there! Personally wouldn't advise cleaning them as they are delicate and you may do more harm than good.

Sundance - unplugging it wont cancel the learning, but the ECU reset will. Generally speaking the ECU goes back to the factory presets, bt as sensors age they start to give minutely different outputs (lambda's degrade etc etc)

Once ECU is reset it tries to aim for a certain idle speed (not sure if these cars hace a switch on the ISCV or use other means to switch to idle mode) and if it cant due to a sensor fault it will learn its way round by effectively adding / subtracting fuel. So you can now see how a reset may end up causing some fuelling probs for a short while.

In terms of performance / fuelling when on the move, its a similar principle. The ECU takes signals from the knock sensor and advances the timing to the point it see's some det and backs off. It needs to do this all the time to take account of things like bad fuel or hot / cold days. This "active knock correction" takes a while (hours) to find a happy point after a reset - so the car may feel fast for a while before it gets fuelling right

Hence some scepticism about some dyno runs

Hope that helps.

MB