Misfiring Vw Golf Mk4 Help!

[AndySil]

What ever you said has to be done after taking off the throttle body/ cleaning it and refitting it.

"the throtle body is 27 on item 24 (inlet manifold) and after cleaning will have to be set up."

[Crasher]

The throttle body is adapted to the ECU.

[AndySil]

OK that's the one then. Please excuse my incorrect terms, I'm not a technician. What I was trying to establish was:- can the job be done (ie. throttle body adapted to the ECU) successfully using Snap-on equipment and will I need a new gasket after taking off the throttle body?

[Crasher]

There are a number of Snap On systems but I think they will all do the TB basic setting. Normally the gasket sticks to the TB and does not need replacing but we always stock one just in case it rips.

[AndySil]

I have the gasket now, hopfully the right one, V028 129 748. it has 4 bolt holes in it.

The two error codes( 17245/17705) haven't reappeared since they were deleted a few weeks ago but I expect them to re-emerge via the engine management light any time now.

Since its been near freezing in the mornings lately the engine has played up more. It starts up no problem but dies as soon as you try to pull away. Have to give it some revs to overcome this and as soon as I have driven 100yards or so, he engine is fine again.

Is this related to the error codes does you think?

[Crasher]

Do another code read now.

[AndySil]

OK not sure if engine should be warm for code reading but this is what I just got with engine cold.

In addition to the two reoccurring codes, 17545, 17705 I got a couple of new ones,17536 and 16955

[Crasher]

17545 Bank 1, Learned value of mixture formation (add*) System too rich

Test fuel pressure regulator and holding pressure
Test injected quantity and tightness
Check valve -N80-, Tank Vent Valve

* add = additive means, that the fault is only effective at idle.


17705 Compressor - throttle valve connection – Pressure drop

Check hose connections


17536 Bank1, Learned value of mixture formation (mult*) System too lean

Testing injection valves
Test fuel pressure regulator and holding pressure
Test injected quantity and tightness
Inspect intake system for leaks
Checking the exhaust system for leaks
Check tightness of the secondary air system
Inspect vacuum lines for leaks

* mul = multiplicative means, that the fault is effective over the full speed and load range.


16955 Brake light switch -F Implausible signal

Check brake light switch and brake pedal switch in measured value block, display group 066

Firstly remove and clean the throttle body and reset in in Basic Settings 060. Then I would fit a new genuine VW dealer supplied exchange Air Mass Meter part number 06A 906 461 LX , replace the split hose under the inlet manifold from the T piece breather valve



(item arrowed in the picture), part number 06A 103 221 BK for a 2003 Golf 4 GTI with an AUM engine and fit a new brake light switch, 1C0 945 511 A RDW.

[AndySil]

Thanks for the info ... very helpful.

Not very reliable these VW’s are they…here’s me thinking my problems would be over getting rid of my MK2 with the 2E2 carb. I was looking forward to some trouble free motoring ….WRONG!!!


I think I mentioned previously that the Exchange Hot Film Air Mass Sensor (part# 0986280217 /£77) and breather Hose (part # 06A-103-221BH /£30) was replaced 4 years ago. Maybe theses weren't genuine VW parts. If they were would they need replacing again?

[Crasher]

Not very reliable these VW’s are they?

Its knocking 10 years old and has done what, 100K miles? What do you expect?

If the hose under the manifold is OK then it is going to need a proper leak test using the VAG pressure testing equipment or a smoke testing machine, there are literally dozens of places the air can be leaking from, if it is that. If the AMM was not a genuine VW part (they have a sicker to say so) then fit a genuine one before going any further.