!.8 Golf Cabriolet Misfire

[yorky19640]

I have a very irritating miss on my 1996 1.8 golf. So far the coil has been changed, plugs and leads, but no difference, have checked any vacuum pipes for leaking but still nothing. Am I now looking at mechanical problems or are there other common faults. The car hadn't been used for 4 months before I purchased it if that helps. Does seem worse when you need to pull up hill, and fuel economy doesn't look good.

[towcestervag]

check the fuel filler neck as these rot and let water/dirt into fuel tank

[Crasher]

Not on a 96, that is a Golf 3 and they have a plastic tank with integral neck.

Double check the angled vacuum pipe to the servo from the inlet manifold on number four runner, these split underneath.

[yorky19640]

Sorry for the late response, but have been away all week. Have just checked the angled vacuum pipe to servo off number 4 and it would appear to almost close up when the engine is running. Not fully closing but must reduce diameter by 2 thirds. Not sure whats causing this.

[Crasher]

Fit a new pipe, it is split.

[yorky19640]

Thanks for that, will try a new pipe tomorrow. Couldn't understand how it could close up if the pipe was split, but not really my thing. Would this explain a misfire and poor performance.

[Crasher]

Yes it would, it massively leans off number 4 which will then refuse to fire the mixture until the revs get higher, a very common problem on the Golf 2 1.6 and 1.8 carb and single point injection Golf 3 1.8 with the AAM and ABS code engines.

[yorky19640]

Have changed pipe and has made a massive difference, however, still have a minor misfire most noticeable when climbing a hill, also notice it when coasting downhill. I did notice a slight spark at base of the metal plug lead end near the plug, so changed the plug. All the leads and plugs have been changed recently.

[Crasher]

Sounds like a duff lead, change it.

[yorky19640]

Have given up for this weekend. Thanks for all the help, but don't seem to be able to get to the bottom of it. Have changed all the leads again and still have this annoying miss, especially noticeable with higher revs. Will try again next weekend.

[Crasher]

So the cap, leads, rotor, plugs and coil are new top quality parts such as genuine, Bosch or Beru? What make is each part?

[yorky19640]

Beru Coil,NGK Plugs, everything else Bosch. Might just be me but top of engine seems to have a very very light tappy noise near 1 and 2 cylinder. Probably me hearing things.

[davidhatton]

i have same probs on my golf 1.8 turbo

[Crasher]

Yorky, I approve of all the parts you have used IF they are the correct ones. I would need the part numbers of the plugs, leads, cap and rotor to confirm this. The coil will be correct; it is what I only use.

David, this is a completely cars different to yours, you must start a new thread with the full details.