1.8T Intermittent rough idle and stall

[The Last Streetfighter]

HI All

I am trying to sort the bugs out before I tune my care.
I have recently done oil pickup, PCV valve, crankcase vent elbow and check valve tee as well as DV and replaced a few vac lines.

I'm now getting an intermittent rough idle which sometimes will cause a stall if I don't give it some throttle. Idle mostly sits 760 - 800 and fairly smooth.

I checked DTCs and only one I get is Immob denied start - Intermittent.
When I clear it, it resets the fuel trims.
I have driven about 15km today and 032 1 is -6.2 and 032 2 is -0.8.

What would be cause of too rich at idle? Ross Tech suggests Air Filter (easy enough to check / replace) but why would that not give more issues at partial?

Any other hints?

TIA

Trev

[h100vw]

Please specify the car. I was assuming Golf but form another post, think it could be an Audi A4??


They never run at 0% anyway, so in isolation, not a drama in my eyes .

What are the sparkplugs like? Throttle body alignment. Probably worth a smoke check. https://www.youtube.com/watch?v=ofFafZfH0HM Put the Fire Dept on speed dial?

Gavin

[The Last Streetfighter]

Cheers Gav.

B5 Passat APU engine.
I'm using copper plugs at the moment and they look fine with a bit of corona. I have not checked the gap: I'll need some feeler gauges or something. I am getting CFs of 6-10 when I log it under boost but no actual misfire counts.

I did a TBA last week. Didn't seem to make any difference.
I guess I'll have to figure out smoke test...

[Umai Naa!!]

There's a solenoid relating to the charcoal canister on these that craps out, and makes them run stupid rich.

Should be on the firewall on the driver's side.Maybe pull the hose off it on the engine side, and see if it makes a difference.

[h100vw]

That's loads of timing pull for a std engine. What fuel are you running? You can pull timing without misfires.

Supercheap sell a two dollar round tool for checking gaps. Anything under 35 thou should be ok on a std engine.

Gavin

[The Last Streetfighter]

91 sometimes but usually 95. Mostly Caltex.

[The Last Streetfighter]

There's a solenoid relating to the charcoal canister on these that craps out, and makes them run stupid rich.

Should be on the firewall on the driver's side.Maybe pull the hose off it on the engine side, and see if it makes a difference.

Can you show me a pic of this solenoid?

Here is what I did tonight.
I removed TB, cleaned it and the IAT sensor and re-fitted.
Removed Air Filter, replaced with new.
Removed ICM and cleaned the surface, added fresh thermal couplant and re-fitted.
Removed #1 plug and checked. BKR6EK. Has dual electrodes on the side with curved tips so you can't really check the gap. Little coating but not too bad. Will order new ones anyway. Probably done 15k km.
I then reset the codes (none) and did TBA. Finished OK.
Then went for a 10km drive. So far slightly better idle, very small idle and partial trims.
Good start.

Now I gotta fix these CFs.

[h100vw]

91 sometimes but usually 95. Mostly Caltex.

Run it right down and put 98 in. Problem solvered. You CANNOT treat it like a corolla. It would be making 100hp.

Gavin

[The Last Streetfighter]

My Corolla had a 10.5:1 comp ratio, so it liked the 98 also.

Here are 2 pulls with much better CFs, on mostly 98RON. The mid range CF that disappears with revs is a little odd.
Now I want to add some boost.

[h100vw]

My Corolla had a 10.5:1 comp ratio, so it liked the 98 also.

Here are 2 pulls with much better CFs, on mostly 98RON. The mid range CF that disappears with revs is a little odd.
Now I want to add some boost.

It depends on what the ECU is requesting for a timing point. Pulled timing coming and going isn't unusual.

Also if the trims are out you should check all the vac pipes under the manifold.

Gavin