Advice please - CIS K-Jet issue - Page 2

urquattr085 · 26-04-20, 07:28 AM

Quote:

Originally Posted by BackintheFold

This is the first thought I had-could it be simply the mixture is badly adjusted?

Quote:

Originally Posted by mikes2

what's the CO emissions like out the back ?

I don't have access to an analyzer, but mixture adjustment via the fuel distributor just makes it run rough or stall, can use around 1\2 turn either way.
CO at last 2 MOT's was 1.802 & 1.928, well within limits. Nothing has changed since then.
Noticeably, Hydrocarbons were also well under at 180.

Could this mean it's more of an oil consumption thing, confusing the issue?

Quote:

Originally Posted by vorsprung durch technik

I remember yours being very rich don't remember it being smokey though!

Oh yes, it puffs a bit getting back on the throttle after overrun, you wouldn't have seen it while I was trying to keep up with you !!!!!
ps - that was an early quad lamp WR, I noticed the smoke too

86audicoupe · 26-04-20, 07:35 AM

Quote:

Originally Posted by vorsprung durch technik

I don't think your alone with this issue Geof, yours and another member who has the same as your version quattro has the same problem.

There was a program last night comparing the Renault 5 turbo and Ur Quattro and the blue car ( MB engine? 10v anyway)
as it went round the corner on a country lane accelerated and out came the blue smoke.
I remember yours being very rich don't remember it being smokey though!

I saw this too, it really annoyed me how smokey it was

4v6 · 26-04-20, 08:33 AM

Id also be checking all the intake hoses and vac pipes for leaks.
You can rough tune it by attaching a vacuum gauge to any manifold tapping and see how much vacuum it pulls under idle when warm, usually around 15 in/hg iirc.
If its lower you can then adjust the mixture and see if you can raise it, wont work if theres any leaks though.

vorsprung durch technik · 26-04-20, 12:51 PM

Quote:

Originally Posted by urquattr085

I don't have access to an analyzer, but mixture adjustment via the fuel distributor just makes it run rough or stall, can use around 1\2 turn either way.
CO at last 2 MOT's was 1.802 & 1.928, well within limits. Nothing has changed since then.
Noticeably, Hydrocarbons were also well under at 180.

Could this mean it's more of an oil consumption thing, confusing the issue?

Oh yes, it puffs a bit getting back on the throttle after overrun, you wouldn't have seen it while I was trying to keep up with you !!!!!
ps - that was an early quad lamp WR, I noticed the smoke too

So is it WR, MB and then RR 20v or is that wrong?

urquattr085 · 26-04-20, 04:21 PM

Quote:

Originally Posted by vorsprung durch technik

So is it WR, MB and then RR 20v or is that wrong?

Chronologically spot on mate

WR up to around 1988 with solid (shimmed) tappets, 2144cc
MB followed with hydraulic tappets, still 10V but 2226cc
RR 20V followed mid 1989

urquattr085 · 26-04-20, 05:00 PM

Quote:

Originally Posted by 4v6

Id also be checking all the intake hoses and vac pipes for leaks.
You can rough tune it by attaching a vacuum gauge to any manifold tapping and see how much vacuum it pulls under idle when warm, usually around 15 in/hg iirc.
If its lower you can then adjust the mixture and see if you can raise it, wont work if theres any leaks though.

Thanks for that
As far as I know, vacuum pipes and intercooler/turbo intake pipes are all ok.
Vacuum pump is on order so will be able to confirm 100% soon.
They are all fairly new though.

urquattr085 · 26-04-20, 05:03 PM

Quote:

Originally Posted by urquattr085

thermo-pneumatic valve ............................ worth a check tomorrow.

Now checked and appears to be working fine.
Another item eliminated

mikes2 · 26-04-20, 08:03 PM

Your CO and HC aren't too bad.

I think the oil consumption needs investigating. Fouling of the plugs could be oil. That would mean a non clean burn.

I'm guessing performance is ok and mpg is normal ?

urquattr085 · 27-04-20, 07:18 AM

Quote:

Originally Posted by mikes2

Your CO and HC aren't too bad.

I think the oil consumption needs investigating. Fouling of the plugs could be oil. That would mean a non clean burn.

I'm guessing performance is ok and mpg is normal ?

Yes Mike, hi 20's - mid 30's if pootling about, normal driving.
Not driven other quattros but I think performance is great.

I'll pull the turbo hoses off and see what that tells me.
Cheers

BackintheFold · 27-04-20, 08:43 AM

Have you checked the compression?
Also, IIRC.... i could adjust my mixture three turns and the engine would run -obviously either lean or rich, but if you can only adjust half a turn that sounds odd to me. A clue perhaps?

26-04-20, 08:03 PM	#18
mikes2 4 ring whore! Classic Audi Club Member Join Date: Nov 2007 Location: Polmont Posts: 2,617	Your CO and HC aren't too bad. I think the oil consumption needs investigating. Fouling of the plugs could be oil. That would mean a non clean burn. I'm guessing performance is ok and mpg is normal ? __________________ 1991 90 quattro 20v sport 1991 90 quattro

26-04-20, 08:33 AM	#13
4v6 Ex Member Classic Audi Club Member Join Date: Dec 2007 Posts: 5,565	Id also be checking all the intake hoses and vac pipes for leaks. You can rough tune it by attaching a vacuum gauge to any manifold tapping and see how much vacuum it pulls under idle when warm, usually around 15 in/hg iirc. If its lower you can then adjust the mixture and see if you can raise it, wont work if theres any leaks though.

27-04-20, 08:43 AM	#20
BackintheFold Senior Member Classic Audi Club Member Join Date: Feb 2019 Location: Near an MB ur Quattro Posts: 1,171	Have you checked the compression? Also, IIRC.... i could adjust my mixture three turns and the engine would run -obviously either lean or rich, but if you can only adjust half a turn that sounds odd to me. A clue perhaps?