Lumpy LCR...please help

[zan]

My car is showing some strange symptoms at the moment and I was hoping someone could help to shed some light on the situation:

When driving at low rev's (1800-2000rpm) the car seems to "stutter" slightly at times. It only seems to happen when holding the rev's at this range and seems fine during acceleration.

I must mention that occasionally when starting the car it will miss-fire for a few seconds and then appears to be fine after that.

I purchased a new coil pack and tried replacing each coil one at a time and test running for a few days to see if a faulty one was causing the problem. Unfortunately, this has not shown any difference and the symptoms still persist.

The spark plugs were also replaced during a recent service.

Any ideas?

Thanks in advance

 

[G3K]

any fault codes?

 

[seatcupramad23]

any fault codes?

x2 do you get fluttering on idle ? try giving TB a clean mate

 

[G3K]

also clean the MAF with electrical cleaner, did mine recently and made a good improvement

 

[welchy]

its the Coolant Temperature Switch or CTS, i had the same problem, cr would missfire a lot when just started and be very lumpy around1800-2000.

Replace it, about £30 from TPS and reset your fault codes... It will show up as a fault code aswell, but not always bring your Engine management light on.

 

[LEE69]

CTS is £8 of ebay lots of us are using them with no problems.

 

[psycho6285]

about £10 from Eurocar parts, mine had the same, fixed it.

 

[t0m]

CTS is £8 of ebay lots of us are using them with no problems.

 

[welchy]

wish id known it was £8, should have done that. Also dont yank it out when your engine is warm like i did, or you'll end up covering yourself with hot hot coolant, got in my eyes and everywhere, not bloody nice!

 

[t0m]

Mine was £6.95 delivered off ebay and was a genuine VAG sensor. The green one

 

[zan]

Firstly, thank you all for the fast replies, this issue has been giving me a headache for a while now.

its the Coolant Temperature Switch or CTS, i had the same problem, cr would missfire a lot when just started and be very lumpy around1800-2000.

Replace it, about £30 from TPS and reset your fault codes... It will show up as a fault code aswell, but not always bring your Engine management light on.

Welchy, this is interesting to find out as I was thinking it was going to be something to do with spark plugs/coil packs or possibly MAP/MAF sensors.

There is no engine management light on at the moment - Was this showing when you had the problem?

Also, is it essential to reset the fault codes after replacing the sensor? (I take it VAG-COM is needed for this?)

Due to the lovely low price of this sensor (The £8 price not the £30 one lol) one will be getting ordered this afternoon.

Again, thanks all for the help on this

 

[t0m]

http://cgi.ebay.co.uk/COOLANT-TEMPE...arts_Vehicles_CarParts_SM&hash=item483e79d0fa

I suppose when I got mine it was £6.95 before the old VAT increase!

Takes 2mins to swap over. Just remember to do it when the car has been sitting for a while or is cold in the morning. Do it after driving and warmed up, and you'll end up with coolant everywhere when you pop the old sensor out.

Let us know how you get on.

 

[zan]

http://cgi.ebay.co.uk/COOLANT-TEMPE...arts_Vehicles_CarParts_SM&hash=item483e79d0fa

I suppose when I got mine it was £6.95 before the old VAT increase!

Takes 2mins to swap over. Just remember to do it when the car has been sitting for a while or is cold in the morning. Do it after driving and warmed up, and you'll end up with coolant everywhere when you pop the old sensor out.

Let us know how you get on.

Cheers Tom,

You beat me to it, my next question was going to be...what part number is it etc!?lol

I will get one ordered tonight and post the results!

Thanks again

 

[zan]

UPDATE

The car failed it's MOT today... for high/erratic emissions!

Took the car to the dealers in Inverness and they kindly ran a diagnostics test free of charge

No faults were found during this!

They recommended adding a bottle of injector cleaner to the fuel to see if this helps so I have taken their advice in the mean time.

Currently awaiting arrival of Coolant Temperature Sensor so fingers crossed this is what is causing the problem.

Bad News - With the MOT failure I cannot get road tax so the car will be off the road until the new sensor is fitted and the re-test is carried out.

Good News - My parents have kindly agreed to lend me the S4 for work for a few days

 

[Cupra neil]

Mines doin exactly the same as yours just got a maf code out of it will try 1 on Monday and see what it's like

 

[zan]

FINAL UPDATE

Relacement Green Coolant Temperature Sensor Fitted on Friday.

Results

• 
  MOT passed on emissions

• 
  Car running perfectly again - No more stuttering/missfiring!

Conclusion

One very happy chappy!

 

[t0m]

FINAL UPDATE

Relacement Green Coolant Temperature Sensor Fitted on Friday.

Results

• 
  MOT passed on emissions

• 
  Car running perfectly again - No more stuttering/missfiring!

Conclusion

One very happy chappy!

Great stuff matey.

Another thumbs up for the Green CTS!

 

[sambryant]

great news, i wonder if mine is causing fueling probs. might have to change it just for the sake of it. i have no faults and temp is perfect on the gauge, worth a try?

just to add, i fitted a new one green cts about 1 year ago

 

[sambryant]

well i just ordered a cts any way

 

[t0m]

well i just ordered a cts any way

Might be faulty, might not mate, but for £7 off fleabay it's worth a shot and you can rule it out if it doesn't fix it.