Power issues

[m_zafar]

I have been having intermitent problems for the last 3-6 months. As I dont drive much, this hasnt really bothered me. The issues are as follows:

1. Engine management lights comes on and will last for around 10 days and goes away
   
2. Standard idle revs are approx. 700rpm. Sometimes this drops to 300rpm. Car statters and revs go back up. This happens sometimes when the car is warm or cold
   
3. Power isnt there when I put my foot down, there is a delay of 2-3 seconds and after a jurk the car accelerates. This happens when the car is warm. I noticed when this happened, when i stop (say at traffic lights) idle revs are all over the place. When the revs reduce lower than 700rpm the clock light dimmers a bit

So heres what ive done to date:

1. The sparks are 10k miles old so i havent replaced them (bosc platinum)
   
2. Replaced the ignition coils yesterday (all 4). This has improved things a bit however today the problem of not getting a responsive acceleration returned. Only had the problem for approx. 5 min in a 1.5 hour drive
   
3. Cleaned the MAF
   
4. Will change the air and fuel filters tomorrow

Any suggestions or recommendations will be welcomed as i have 4 days off so I can try various things.

 

[Big_daddy]

Do a ecu reset and if you have vag do tb reset, at the same time check for faults.
Also check all you hoses and inspect you DV.

 

[m_zafar]

ecu reset? hows that done? Unconnect the battery?

whats a DV mate and where abouts is it?

 

[Big_daddy]

ecu reset is done, disconnecting battery for 20mins aprox, reconnect battery, turn on ignition, wait for 2mins (allows time for the tb to stop making the noise under the bonnet). then start engine.

Dv - Dump valve, its on the intake pipe next to air maf. ( you have to take off the engine cover to see it.

 

[m_zafar]

ecu reset and took it for a run, idle revs drop to 600rpm and then jump back upto 700rpm for 4secs. Turbo lag still exists. Turbo was struggling to kick in on a few occassions while driving on a 6 mile strech. Early days, will check tomorrow as well. Theres no engine management light on. Dump valve looks inplace.

Will Vagcom show anything?

 

[goble]

CHANGE the air flow meter

 

[caveo]

yep sounds like an air flow prob so check maf and hope its not a turbo issue

 

[Big_daddy]

ecu reset and took it for a run, idle revs drop to 600rpm and then jump back upto 700rpm for 4secs. Turbo lag still exists. Turbo was struggling to kick in on a few occassions while driving on a 6 mile strech. Early days, will check tomorrow as well. Theres no engine management light on. Dump valve looks inplace.

Will Vagcom show anything?

Yeh vag should show it, but if its a dying maf it wont come as a fault, you would need to do some logs measurements on the maf, follwed by the boost runs (actual vs reqested).

Hope this helps cuz

 

[m_zafar]

i will disconnect the maf and see what happens (im assumming this is how the maf is tested?)

 

[caveo]

no not really just check its in right and then revert toa garage to check the fault try jbs in chesterfield if ur near by

 

[G2232]

the best way to see if its a bying maf is disconect it if it gets a whole lot worse its not likely to be that but if its doesn't change or only gets a little worse theres your problem

 

[m_zafar]

Heres an update:

Coil packs replaced
MAF cleaned
Trottle alignment
Checked DV

Results:
Idle revs have improved
Turbo response has improved

I drove the car for 30min yesterday and an hour today.

To summerize:

Things have only improved as the problems still exist (the car is moody).

I will evaluate over the next 2 days. Next steps will be:

Replace the MAF
Replace the N75

Found Andys post very useful:
http://www.seatcupra.net/forums/showthread.php?t=27782

 

[Big_daddy]

Maf still could be knackered even if its cleaned, recommned get it on vag before buying things that dont need replacing.

 

[Hicks]

I replaced the N75 valve on mine (after dealer diagnosed a fault with this), and also did an ECU reset. Thought this had cleared up the problem, but a week later and it's back with a vengance - car stalled itself on idle the other day!
I disconnected the MAF and the car ran perfectly smooth, although way down on power. I now have a replacement MAF which I'll try over the weekend.

 

[m_zafar]

How much is a MAF, i asked GSF however they didnt seem to know what it was. I assume is also known as something else as well? Are there specific high performance ones as well or should i go for a standard one? Exact model no will be cool

 

[Hicks]

Local dealer: £64 + VAT. But because this is an exchange part, they will also surcharge you £20, which is refundable if you give them your current MAF.

Eurocarparts: £57 + VAT

However I just bought a MAF from someone advertising in the 'accessories for sale' section on SCN for £25. I know he has another one if you want to buy that.

 

[Big_daddy]

How much is a MAF, i asked GSF however they didnt seem to know what it was. I assume is also known as something else as well? Are there specific high performance ones as well or should i go for a standard one? Exact model no will be cool

Well i paid approx 80 quid for mines from GSF px with my old maf. Sure you rang GSF not the Ali baba the corner shop next door
May want to say Air mass meter or air flow meter. they will ask 4ur car reg to confirm right part number.

 

[m_zafar]

Well i paid approx 80 quid for mines from GSF px with my old maf. Sure you rang GSF not the Ali baba the corner shop next door
May want to say Air mass meter or air flow meter. they will ask 4ur car reg to confirm right part number.

Wasnt Ali Baba, Dave at the chadwell branch. why px?

 

[m_zafar]

Local dealer: £64 + VAT. But because this is an exchange part, they will also surcharge you £20, which is refundable if you give them your current MAF.

Eurocarparts: £57 + VAT

However I just bought a MAF from someone advertising in the 'accessories for sale' section on SCN for £25. I know he has another one if you want to buy that.

£25, yes please. Can you PM me. Thanx

 

[Big_daddy]

Thats a good price, you want find it cheapeer any were.