Need help. My golf has a problem with the engine.

[Riccardo]

Hi all my 2004 golf has what feels like a misfire. But I've done spark plugs and spark plug leads and it hasn't gone away. I'm just wondering if any one has had a similar problem or if any one can help.

[Lucas_R]

Which engine?

Have you checked the distributor cap (providing it has one depending on the engine) for cracks/water inside/corrosion/damage. The distributor cap would be the next logical item to check/replace after your spark plugs and leads.

[Riccardo]

It's a 2.0L petrol

[Riccardo]

It's a 2.0L petrol.

[gldgti]

Hey mate,

The 2.0L is a bit susceptible to running rich if the MAF is dirty, which seems to carbon up the plugs etc. Does it blow black smoke when you rev it/ does the exhaust smell rich?

I would try pulling out the MAF and spraying a can to carby cleaner or maf cleaner through it (start ya bastard does the same thing and is cheaper than 'maf cleaner'... they are all just ether anyway).

I would also get it scanned with VCDS, could be something like a faulty knock sensor aswell.

(Dirty MAF can be caused by 'performance' oiled cotton air filters).

Also if the o2 sensor has a problem the car might be running in open loop/warmup mode which can also cause it to run too rich.

**EDIT** if you open up the intake and take a look at the MAF and its clean as a whistle, dont bother trying to clean it. It should be obvious if its dirty.

[dylan8]

The maf doesn't just fail after a number of km anyway.
When you say it feels like a misfire, what's happening exactly?

[gldgti]

The maf doesn't just fail after a number of km anyway.


But the o2 sensor or a knock sensor could.

Or the MAF might have become contaminated suddenly due to some other unforseen event. For instance, some kind of vermin ate through part of the wiring harness on the engine on my audi. I dont see why one couldnt also munch on someone elses wiring harness, or equally eat a hole in the air filter ;-)

[Riccardo]

At idle it has a jumping feel when I'm stationary but when I start drive it all goes away. It comes back when I stop.

[JustCruisn]

By jumpy as idle do you mean the idle falls and rises (hunting), this is often caused by a vacuum leak. Old car the lines perish.
They can be fun to locate, fell around for moving air, or listen for a leak, but a smoke test would find it pretty quick.

[Riccardo]

Yes but very little rises and drops.

[dylan8]

mines started doing similar, not enough to worry me but will investigate a vacuum leak.
everything else sensor wise in my car is pretty fresh so id hope its none of them