Running Lumpy and Cutting out :(

[Clemstar]

Hi

Newish Cerbera Owner, 1997 4.2, Car seems to be running lumpy and cutting out at junctions (very embarrasing) it just wont idle unless you hold it on the accellerator. Also smells of petrol when driving along!

Also any specialists in the North East that service these cars that anyone could recommend

Any ideas ?

Thanks People

[trooper1212]

Could be loads of different things. Mine had just had one of the coil packs replaced after similar problem.

Most likely one of the following:
Lambda sensors
Coils
HT leads
ECU

How northeast are you? Joospeed is around the Nottingham area I think.

[SXS]

If you can smell petrol, and she's running lumpy...

I'd check that all the purple pipes are tightly fitted, and there are no leaks....

and then

check your throttle pots.... (big culprit behind your symptoms)

[andy4200]

No purple pipes on a 4.2, we aren't graced with such lovely underbonnets.

[Clemstar]

Throttle Pots have been done I think, Im in Durham area, but I think a trip to Joospeed maybe on the cards!

[RichardP]

It just sounds like it needs setting up properly - balanced air flows and throttle pots etc.

[joospeed]

Good answers one and all .. unfortunately could be any one of them .. bugger.

joo

[christmc]

I have had the same problem with mine,,,it was a temp sensor on the engine which regulates how much fuel is pumped into the engine dependent on its temp,,i dont claim to be anywhere near as clued up as most of the guys on here but thats what made mine stall all the time ,,,pretty cheap to sort if thats all it is

[bilton_d]

I can't say anything but good things about Hexham HC give them a bell 01434 601666

[SXS]

Have you tried maybe using Optimax and/or hot shots/redex injector cleaner???? sometimes that helps...

if not... and you want a home made (cheap) solution...
take off the service strip, and turn the bolt that holds the idle lever, up a little, and increase idle revs a little - its cheap, but helps, till you get round to getting it sorted properly?

[sethlj]

Water in the ECU - that's what caused my lumpy running/cut outs. That was after balancing, a bit of sheilding, replacing Lambdas, throttle pots etc. etc.

Get somebody who knows what they are doing is my advice.

S.

[gary judd]

hi
first and most simple thing to do is unplug the ecu leave it for half an hour and replug it. it worked for me then if that does not work it will probarbly need setting up on a computer and that takes no more than 1 hour
good luck
gary

[Clemstar]

sethlj said:

Water in the ECU - that's what caused my lumpy running/cut outs. That was after balancing, a bit of sheilding, replacing Lambdas, throttle pots etc. etc. Get somebody who knows what they are doing is my advice. S.

I think you possiblly right with that one mate, just took her out and filled it up with optimax - no difference but ive noticed that the floors are wet from the shed loads of rain weve been having on both sides, wheres the ecu ?? passengerside?. Did you have to have a new ecu or did they dry it out ??

[sethlj]

Clemstar said:

wheres the ecu ?? passengerside?. Did you have to have a new ecu or did they dry it out ??

ECU is in the passenger side footwell so I am told. Mine was dried out and all ok - but there was a bit of green copper corrosion on the connectors!

It turned out that when I washed my car on my sloping drive with the nose pointing up hill the water was running under the bonnet and down the loom into the ECU. To stop this you can mount the ECU differently - or not wash the car! If yours is getting wet then you may try a remount.

Once this was done and dried out on mine I never had the problem again. Mind you it did need resetting after it got wet so you will need a laptop or TVR specialist!

Have a look at this thread where the full story of my soggy ECU is told.

Best of luck.

S.

[Julian64]

Possibly easy solution here is to pull the ECU off its velcro fixing system turn it up the other way and stick it back on. Never seen water run upwards.

Yes, its in the passenger footwell, in a superb place to get kicked by the six foot yobbo your taking for a test drive when he tries to put on the passenger emergency brake.

[Clemstar]

sethlj said:

Clemstar said: wheres the ecu ?? passengerside?. Did you have to have a new ecu or did they dry it out ?? ECU is in the passenger side footwell so I am told. Mine was dried out and all ok - but there was a bit of green copper corrosion on the connectors! It turned out that when I washed my car on my sloping drive with the nose pointing up hill the water was running under the bonnet and down the loom into the ECU. To stop this you can mount the ECU differently - or not wash the car! If yours is getting wet then you may try a remount. Once this was done and dried out on mine I never had the problem again. Mind you it did need resetting after it got wet so you will need a laptop or TVR specialist! Have a look at this thread where the full story of my soggy ECU is told. Best of luck. S.

Im convinced its to do with water, as Unfortunately I had to leave it out in possibly the worst rain Ive ever seen! Also Ive take it out today and its been dry up here for the last 2 days and it seems a little better. But still cutting out when taking foot off the accellerator from higher revs whilts stationary, But if you gradually let the revs slow down it will actually idle, albeit a bit rough. Im going to take a peek at the ECU over the weekend to see if its wet or been getting wet. Hopefully thats all it will be (Fingers Crossed)