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VW Golf 2.0 8v AGG 1996 - Running weak #

Posted by Glen Strachan on February 28, 2013, 2:15 pm

Year of Manufacture *: 1996
Engine Size and Code *: 2000 AGG
( Optional ) ECU Type: SIMOS
( Optional ) Scanner Used: KTS VagCom

Got an old P reg VW Golf running weak.
02 sensor stuck 0n .21v
Fuel pressure running at 3 bar ok and flow test OK.
If I clamp off the return pipe and raise the pressure to between 6&7 bar the idle smooths out and the 02 starts switching.

Has anyone ever had injectors blocking up on these ?
Can they be cleaned or tested ?

Re: VW Golf 2.0 8v AGG running weak

Posted by keith brown <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1429' width='330' height='300' border=0 style='border:none;'> on February 28, 2013, 4:48 pm, in reply to "VW Golf 2.0 8v AGG running weak"
Keith Brown

have you a scope
you could watch needle lift & fall
worked realy well for me with an alfa recently

Re: VW Golf 2.0 8v AGG running weak

Posted by Glen Strachan <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat1463' width='330' height='300' border=0 style='border:none;'> on February 28, 2013, 5:09 pm, in reply to "Re: VW Golf 2.0 8v AGG running weak"

I do have pico, but have not yet scoped the injectors as I didn't really know whether a scope trace would show the fuel delivery.
I apreciate I would see the spike and be able to confirm injection duration, but would I see from that a bad spray pattern ?
I guess if only one was bad I may be able to see it, but there is no missfire, just a big flat spot

Re: VW Golf 2.0 8v AGG running weak

Posted by Pete Mutlow <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1569' width='330' height='300' border=0 style='border:none;'> on February 28, 2013, 6:39 pm, in reply to "Re: VW Golf 2.0 8v AGG running weak"
Peter Mutlow

Hi Glen,

Exhaust emissions? Fault codes? air leak? Maf?

Regards

Pete M

Re: VW Golf 2.0 8v AGG running weak

Posted by Glen Strachan <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat1463' width='330' height='300' border=0 style='border:none;'> on March 12, 2013, 1:46 pm, in reply to "Re: VW Golf 2.0 8v AGG running weak"

Still ongoing
Customer supplied a used set of injectors c/w rail and that has made no difference

Exhaust pressure test proved ok

drilled into the front pipe and took pre cat emissions tests well clear of the O2 sensor

at idle
CO 0.11 HC 560 C02 7.31 O2 11.6 Lambda 1.986

Fast idle
CO 0.09 HC 296 C02 4.03 O2 15.83 Lambda 3.488

I have confirmed timing with KTS and compression is good

Lambda fault keeps returning when the voltage gets to 0.2v Again, if I squeeze the return pipe and raise fuel pressure to 6 bar the O2 switches ok

Re: VW Golf 2.0 8v AGG running weak

Posted by ray ferreday <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT5108' width='330' height='300' border=0 style='border:none;'> on March 12, 2013, 4:26 pm, in reply to "Re: VW Golf 2.0 8v AGG running weak"
Raymond Ferreday

try disconnecting air mass and see how it runs as these are common for failing ray

Unresolved #

Posted by Glen Strachan on March 15, 2013, 8:10 am, in reply to "Re: VW Golf 2.0 8v AGG running weak"
Edited by board administrator March 15, 2013, 10:36 am

Thanks Ray, I have tried an air mass meter.

Customer gone out and bought another car

Its driving me insane that something so simple is causing so much of a problem

Looking at the emissions results I would say it has a massive air leak, but I cant find it.
After sleeping on it, I have decided I am going to call him later and try and buy it off him because I cant let it go

Glen

Re: Unresolved #

Posted by Pete Mutlow <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1569' width='330' height='300' border=0 style='border:none;'> on March 15, 2013, 7:01 pm, in reply to "Unresolved #"
Peter Mutlow

Evening Glen,

I wonder if the emission figures you have given are accurate. On my gas analyser, I need to get the probe fully inserted into exhaust to provide accurate figures. On the odd occasion, when running at fast idle to measure the emissions, the probe sometimes comes out and gives similar figures you have provided. You have drilled a hole into the exhaust and I wonder if the probe is fully inserted. I am not sure why you used this method which is normally used to test the integrity of the catalytic converter (before and after figures). I would prefer to see the figures at the tail-pipe in your case.

Finally, if you can't hear or trace an air leak using the normal methods, maybe you might have an "internal" air leak such as a brake servo?

Regards

Pete M

Re: Unresolved #

Posted by Mark Carter <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1428' width='330' height='300' border=0 style='border:none;'> on March 16, 2013, 7:56 am, in reply to "Re: Unresolved #"
Mark Carter

>>> I am not sure why you used this method which is normally used to test the integrity of the catalytic converter <<<

I sometimes like to see the untreated values to get a better view of whats going on.

Mark

Modern cars, Its all wizardry and witchcraft

Re: Unresolved #

Posted by Pete Mutlow <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1569' width='330' height='300' border=0 style='border:none;'> on March 16, 2013, 9:15 am, in reply to "Re: Unresolved #"
Peter Mutlow

Yes, I agree your point Mark. However, I wouldn't go to the trouble of drilling a hole into the exhaust pipe to see whats going on. Bring back the days of the "sample pipe"!

Regards

Pete M

Re: Unresolved #

Posted by Mark Carter <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1428' width='330' height='300' border=0 style='border:none;'> on March 16, 2013, 1:23 pm, in reply to "Re: Unresolved #"
Mark Carter

>>> Bring back the days of the "sample pipe"! <<<

And the Hovis advert.

Those were the days !!!!

Modern cars, Its all wizardry and witchcraft

Re: Unresolved #

Posted by Glen Strachan <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat1463' width='330' height='300' border=0 style='border:none;'> on March 18, 2013, 1:14 pm, in reply to "Re: Unresolved #"

I went into the front pipe so I could be as sure as possible that the readings were unaffected by the cat. And at the same time I could check exhaust pressure wasnt too high. It is a quick easy test, I buy lambda sensor 'holes' so after the test I can just screw in a bung.
The only other clue was that when the manifold was off the valves were spotless and so were the crowns of the pistons. Everything looked washed clean to the point of looking virtually new.

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