Running issues - Cant seem to resolve!

[N2AE86]

Gents,

Hopefully someone can offer some useful insight.

Wife took the old golf out for a spin the other day - 1.8 Driver (ADZ) and it ran like a bag of spanners!

Since then I have been chasing problems!  I have swapped out the ignition components for new parts (including a new diz).  But the car still seems unhappy at idle.  Rev counter bounces 1/200 rpm and sounds a little lumpy and its running really rich.

I have been going backwards and forwards with the timing and I cant seem to get it nailed (mechanically the engine is timed up properly) but ignition wise its either pinking or retarded.  I cant seem to find a middle ground at all and the car doesn't like starting and needs a jab of the throttle to get it going.

I have subsequently changed out the lamda sensor (no change) and will be replacing the engine temp sensor shortly.  Is there something that I am possibly missing, or a common issue I don't know of?  Running out of things to replace.

Plugged the car into the OBD controller and its clear as well!?

Thanks in advance for the help!

[Leon27]

The coolant temp sensor is a good one to replace - I had issues with mine on my GL.

Also would advise to check the throttle mounting flange:



Mine was split and the throttle body wasnt secured to the inlet.

From your fault I'd also check all your breather hoses, make sure they haven't gone soft and collapsed and make sure the crankcase pressure isn't too high.

[N2AE86]

Thanks for the reply Leon!

The throttle mounting flange seems good - had it perish before.  Really need to take it off an inspect to be sure but cant see a split in it and misting water around the flange when the engine is running doesn't seem to affect the engine running so a hidden leak seems unlikely.

Checked all the pipework and it seems fine.

Hoping the temp sensor will sort it.

[itavaltalainen]

Measure the resistance on the temp sender. I posted a link to a how to on here quite a few times.
http://www.motor-talk.de/forum/aktion/Attachment.html?attachmentId=719242

If you have diagnostics have a look at measuring blocks alternatively. You can read the temperature from ECU as well and it should be reasonably close with temperature in dash (though on MY95 on the gauge is dampened and will always show 90 from around 80-100 degrees).

When you say you swapped dizzy, do you mean just the rotor and cap or the complete distributor?

You changed lambda... was lambda running out of spec on the measuring blocks or was it just shot in the dark?
The other issue 1.8 suffer are broken gears on the throttle angle adjuster. They're just small plastic gears, might be worth taking that off and checking that there aren't teeth missing.
Lives on the throttle body assy and looks like that: http://i.ebayimg.com/t/Drosselklappenansteller-VW-Golf-3-Polo-Seat-032133031-/00/$(KGrHqMOKogE3EnFIVPQBN7mtEw(5!~~_12.JPG
Gears look similar to this: http://www.coolchip.de/_polo/drosselklappe/pic/mechanik2.jpg

good luck.

[N2AE86]

Thanks for the suggestions!

To answer you questions -

I replaced the whole diz unit, plus cap and rotor.  Swapping the O2 was just a shot in the dark.  I have suffered from the TPS issue you mention but when I did the TPS caused really erratic throttle behaviour and the car (when it does run properly is as smooth as silk - still thats on the cards to be checked over).

So the update!  No real change!

The car managed 30 sedate miles on £20 fuel so its really overfueling!

Popped a new temp sensor in and it hasn't helped the running.  Found another old temp sensor in the garage and also tried that and no improvement so it doesn't look like its the temp sensor.  Just wondering about the wiring - pulling the lead to the temp sensor doesn't seem to affect how the engine runs when warm, and only occasionally when its cold / starting up. 

Started the car yesterday after changing the sensor and it was idling rough like it was running on 3 - (but pulling the leads one by one show its still running on 4 - just really badly)

Pulled the plugs and they were black - cleaned them all up and also did a compression test which shows all 4 cylinders are showing good compression.

Replaced the O2 sensor with the old one - new one is black (no surprise considering the plugs) and that didn't change the running.  Also swapped on a different lead set but again didn't effect the running either.

After I had cleaned the plugs and got the engine warm the lumpy idle went away.  Got the light out and timed it - pinks like a b!tch, the smallest adjustment the other way and its retarded and there is a delay in throttle response.  Still clearly all over the shop fuel wise!

Can anyone tell me what the timing process is for the ADZ lump just incase I am missing some trick - like pulling certain sensors / setting it at a certain RPM etc?

[itavaltalainen]

How did you do ignition timing? Did you tell ECU to do basic setting so that it does keep ignition timing constant?

[Danholmes]

Did u ever sort this issue I'm having same problem

[Jasikasisback]

1. Does your car almost choke to a standstill on start from cold?(engine sputters) . Come to a junction and same thing?/Idlind in traffic is rough?
2. Does it have really bad fuel economy in the city but half decent highway?
3. Have you checked the small hoses to the throttle body housing to see if they have perished?
4. Temp guage goes down in motorway with heater on full blast at cruising speed?

[spud72_uk]

Also having the same problem with a 1.4 ABD engine.
So far - replaced dizzy as was cutting out ( Hall effect sensor ) now fixed.
New plugs
New coil
3 new temperature sensors
Timing re done with the help of this forum
excessive fuel consumption 1/3 tank for 40 miles
plugs and lambda sensor very black
CAT not rattling
Temp when driving wont go above 70c - 2 new thermostats fitted

Running out of ideas - thanks

[Valere Oddoux]

Have you tried cleaning the throttle body with one of those spray can (the foamy one you use while the engine is running through the air intake hose)?
That help mine
Good luck