A4 1.8T (163bhp) - lack of power

[richjthorpe]

Hi all,

I have a 2003 1.8T (163bhp) which had a new turbo fitted just before Christmas and all was well. Since then I've had the misfortune of 2 coilpacks failing within a week of each other meaning I've now replaced all 4.

I've recently noticed a lack of power over 2500rpm, I would expect a surge of power while in 3rd but it gentley applies the power and 4th or 5th are worse still. I feel a surge from 2000rpm in 1st but previously this would kick in around 1800rpm.

I've had a quick read up about the N75 valve but don't know if this is the culprit or one of the vaccuum valves somewhere

What should I be looking for or tests I can do to trace the fault?

Thanks,

Richie.

[papalion]

have you had any luck on this ? seems like the same problem as me .

[bez101]

Hi all,

I have a 2003 1.8T (163bhp) which had a new turbo fitted just before Christmas and all was well. Since then I've had the misfortune of 2 coilpacks failing within a week of each other meaning I've now replaced all 4.

I've recently noticed a lack of power over 2500rpm, I would expect a surge of power while in 3rd but it gentley applies the power and 4th or 5th are worse still. I feel a surge from 2000rpm in 1st but previously this would kick in around 1800rpm.

I've had a quick read up about the N75 valve but don't know if this is the culprit or one of the vaccuum valves somewhere

What should I be looking for or tests I can do to trace the fault?

Thanks,

Richie.

try the dirverter valve better known as the dump valve

[wmccann]

have you tried the air mass meter?

Walter.

[richjthorpe]

Changed the Air Volume Meter mid last week before a trip to north Wales for the weekend. Seemed to do the trick. It stutters slightly at low revs but I'm happy at the moment.

I can hear the turbo spool up so don't think it's the diverter valve.

Thanks all,

Richie.

[richjthorpe]

OK, so the misfire hasn't gone away yet.

I've had replaced the:

MAF sensor
Coilpacks (All 4)
Plugs
I'm going to check the vacuum hoses and try to get the VAGCOM linked up. Any ideas? I'm having to run on Super Unleaded in order to get over the misfire.

Richie.

[docurley]

I would swap out the spark plugs and may be upgrade the DV.

[richjthorpe]

I only swapped the plugs a couple of months ago but it could well be. Where's the Diverter Valve?

[motechmike]

it will be an air leak.. very very common and a pain to find !

[wmccann]

Audi in all its wisdom used on my 2.4 a "solid" plastic air pipe which becomes very very brittle over time with the heat of the engine - madness!!

Be very careful if you have the same as just touchig it will cause it to shatter. I had to use Duck tape on mine until I got a new pipe at €30+

Good luck in finding the leak,

Walter.