Misfiring Vw Golf Mk4 Help!

[Crasher]

If you have a shareware version of VAG-COM you can't have performed the throttle body re-alignment after cleaning it. The other codes could be down to an air leak and the crankcase ventilation system is a common culprit. You need to do the TB alignment before you go any further and take a look at the small diameter breather hose that comes out of the crankcase ventilation unit on the front of the block. Also check the rest of that ventilation system but it is very difficult to get at.

[Shleng]

yeah i have to take it to a mate of mine at VW to get it done but i havnt had a chance to get there yet. one thing that has been common recently is that it seems to misfire approximately 2-3 minutes after setting off wheras it previously happened imidiately after ignition 2-3 seconds! this seems to be the case having cleaned the TB. not sure if this sheds any light at all. i do plan to check the connections of all the breathers. The car has not been as bad since i have replaced the 2 damaged ones about a month ago. There could still be another but like you say there not easy to examine, specially when the only time you can look at it is after work when its almost pitch black!
is there any test that you can do on the breather system without having to take each individual prpe off or check its connection (i.e. pressure tests?)

[Crasher]

There is a pressure test method but you need some pretty serious kit to do it, removing and inspecting is the best way. On my VRS I found the hose from the crankcase breather "T" piece valve to the inlet manifold was split under a rubber jacket and the only reason I found it was that the engine was spotlessly clean after I replaced it then and later I noticed oil creeping out of the side of the jacket.

[funtime]

Im having difficulties with my car too..it seems to misfire, the revs move up and down, however they do become stable sometimes, it is so annoying though..what could the probem be???

i've been reading up on various articles, theres so many suggestions, the most popular one(s) being:
~ coil pack
~ spark plugs
~ egr valve
~....etc

How would you know which one is to be replaced??
It costs an arm and a leg to get all of them changed, especially when labour cost more than the parts sometimes, theres no point tryin trial and error unless uv got money pourin outta yo backside..

I hope someone can help..would really appreciate it.

Cheerz (",)

alot of people forget to check breather hoses if they split they will suck in too much air this produces a weak mixture inturn this will create a miss fire...

[Crasher]

alot of people forget to check breather hoses if they split they will suck in too much air

Not only suck but on a turbo engine the allow boost to escape which causes poor acceleration delivery which is what we were talking about above. The pipe in question leaks under vacuum and boost and is a common problem on the 1.8T as they age.

[suni4real]

Hiya guys,
I took my car to the garage, they put it onto a diagnostics machine and guess whats..nothing...i dint know wether i should be jumping for joy or to or pull my hair out..lol

I've got another problem though now..i used money more than brain today, i bought a Turbosmart dump valve today within 20 minutes of head turning around town two lights have switched on..from my understanding. ONE is the TRACTION CONTROL LIGHT & the other is the ENGINE MANAGEMENT LIGHT, should this have happened i paid 160 quid for this peice of gear..
Now these stupid yellow symbols on the DASH have become so annoying; it makes me not want to drive..
How can i put this right?? If i replce with my standard BOSCH one would the problem go away?? or are the lights going to stay on until Ivisit VW dealers???Sorry im clueless.
The garages around here just want to descimate you out of your pockets and i really dont want to be a victim..
perhaps one of you wise and smart guys can help???

Plz Help??!!
Would definetly be appreciated..

[Crasher]

External venting or non original valves can cause engine running problems, I will only use the APR R1 which so far have not caused me or my customers any issues and they are quieter than the original so you don’t look like a knob when driving the car. I have removed more aftermarket valves than I have the unreliable original VAG items, get another fault code read done to see what has happened.

I won’t even fit this rubbish, new mind sell it. They should come with a Burberry cap, white shell suit an imitation thick gold chain included in the deal, and they would be worth more than the stupid valve as well.

[Shleng]

still struggling crasher!!! im trying to get my mate at vw to have a look at my engine to see if he can shed any light on the problem that i am experiencing but hes always busy. i now have access to a registered version of vagcom and have removed all DTCs and readapted the TB. the main fault that i am getting now is that the G28 sensor is showing an intermittant fault. where is this sensor located? (its a 1.8t AUM 2002) i assume that it is on the block somewhere as it is measuring the engine speed. if this has a poor connection could this cause the car to refuse to start after it has stalled at startup? when the car begins to fire after playing up some mornings, it misssfires badly. if you keep trying to turn the engine it begins to start after plenty of turning of the engine and then returns to normal after 30 seconds or so of warming up.
basically i just want to check the connections of this sensor as a last resort before admitting defeat and handing it over and spending mass amounts of money but i am struggling to find any info on the net as to where it is located.
cheers

[Crasher]

The sensor is at the front of the engine down near the sump and bolted through the block right up against the gearbox end so that it points at the 60-2 disc which is bolted to the rear web of the crankshaft. It is quite rare for these to play up.

[ferretboy]

Hi, Im having misfire problems too. Its a 2002 golf 2.0 gti, engine AQY. The car performs fine but when sitting still the rev needle moves up and down ever so slightly. The engine management light is constantly on now now. Any ideas?