Erratic throttle response when cold

[Delboy]

Originally Posted by HPsauce

My Clic-R pliers arrived today and as the rain finally stopped I've been out to investigate the PCV valve.

Undid the clip for the side connection easily enough and eased the pipe off, then with wiggling and brute force with pliers managed to move the clip underneath round until it was accessible and undid that too.

Removed the PCV valve and finally, now I could access it, undid the idiotically-oriented jubilee clip fixing the short flexible tube underneath to the metal pipe below it.

Took the valve apart, which needs care and a bit of force - I used a large flat-bladed screwdriver to lever open the catches a tiny bit at a time, working round.
Took the diaphragm out carefully and checked it was in good condition.
It looked fine though a bit oily so I cleaned everything thoroughly with white spirit and isopropanol and reassembled carefully. I then checked (by sucking/blowing on the ports in turn while covering/uncovering the other one) that it was working OK and not leaking.

Put it all back on the car, ensuring that both Clic-R clips and the jubilee clip were oriented for easy access in future. . Ran car briefly to check it was OK.

Time will tell I guess whether the problem is still there.

Footnote on the Clic-R pliers. The ones I bought were pretty cheap and didn't work that well (at first), especially for reclosing the clips.
Looking at videos online and pictures of seriously expensive ones I could see that the blades were poorly shaped. They had been initially forged or stamped then ground to shape inadequately. Quickly fixed with a metal file.

For reference, if anyone else gets these and has problems, the pliers are asymmetric; one side is a wedge, the other more like a chisel.
The problem with mine was that the "outer" face was rather rounded, from poor finishing, resulting in a thick working edge of varying thickness that prevented them making a good contact in the right place on the clip. I filed them down giving good flat working surfaces with narrow (but not sharp) edges where they press on the clips. The chisel edge in particular need to be quite thin to work properly.

Glad you got the somewhat correct tool for the job, were the clips easily put back on now that you modded your pliers?

[HPsauce]

Yes, they went back easily once the pliers were "flattened".
As delivered they had a bulge in the metal that lifted the blades away from the place where they needed to be. They have to make contact under the two locking components in order to force the two ends of the clip to overlap and latch together.
Mine were very like these but not so "sharp" until I filed them:

[HPsauce]

Originally Posted by HPsauce

Time will tell I guess whether the problem is still there.

Had to go out this evening; it behaved OK including a couple of "brisk" exits from side roads very soon after starting (within 200 yards) which normally show up the problem. Fingers crossed.

[Sir WIll]

Took mine out today, my little orange rubber seal it split.

Poor thing time for a new one.

[HPsauce]

Originally Posted by HPsauce

Had to go out this evening; it behaved OK including a couple of "brisk" exits from side roads.

And on a fairly lengthy "day out" today with long and short runs and several long breaks, about 200 miles overall it's been fine.

Maybe my imagination but the throttle response seems "sharper" too.

But as noted earlier, only time will tell. And I put another £100 of Shell Nitro in this evening to make sure fuel is not the problem.

[HPsauce]

Originally Posted by HPsauce

only time will tell.

Yesterday, with a number of short runs, I had a "hint" of misbehaviour on one occasion.

Today I've cleaned the MAF sensor and will "await developments".

On the basis of only ever changing one thing at a time (if at all possible) when diagnosing problems, what would people change first if problems continue - the PCV valve or the MAF sensor?
(neither job is difficult but the PCV is cheaper)

[HPsauce]

Hmmm, definitely NOT cured.

Today, on my way out (to meet up with Adrian E & johnny_quattro) I had a definite lack of power turning left out of the bottom of my road onto the A-road (both 30mph limits). I had just "pootled" downhill gently to the junction from a cold start, maybe 300 metres at 25mph or so.
A quick "twitch" of the accelerator and it was back to normal and I joined the main road with some urgency! No further symptoms all day.

Just wondering if it could be in any way gearbox-related, i.e. sticking in a too-high gear as it slows down.
Would flicking the lever across to tiptronic mode as I slow down at junctions enable me to see anything useful in the DIS if it was?

[notorious]

HP,

I'm going to change on my D2 2002 both MAF and PCV valve this winter.
I'll do MAF first and then PCV valve.
Same applies to lambdas and spark plugs.
I'll use genuine Audi parts.

I have no problems with performance and there are no errors.
It's just 10 years old car.

[HPsauce]

I ordered a new PCV valve from the USA in the end (cheaper) and it arrived on Saturday. Fitted this morning; now I know how (and have the right tool) that took under 10 minutes.

Just had a couple of short trips since, all OK so far. Fingers crossed again.

[HPsauce]

Originally Posted by HPsauce

all OK so far.

Sadly, it misbehaved a couple of times in recent days. No codes logged, so new MAF on order.