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Faster than Jeroen this time You guys are fast!

Thanks a lot. Time for a full ajustment tomorrow...

Hi guys,

Had my CO adjusted. The mecanic who did it prefered to make HC drop just until it starts to go up again. That should tell that it is the point where it gets the right mixture. The figure for CO was then 1.88 and HC was lowest at 78.

Now the car runs perfect when warm, and acutally allso after cold start. But still in between cold and warm something is not right. About 2 mins. after starting the engine gets unstabile. It does not roll and you can't see it on the rev meter. It is like a cylinder is partly missing or the ignitions fails frequently. I took the spark plugs out and they are alle dry and Brown. Allso changes the little hose from the throttle house as it was leaking. The breather from the valvecover is quite easy to take off so just tryed to put on a clamp, but no good.

When the engine is fully warm it runs perfect. I can leave the car for one or two hours and try to start it - and it starts right away. At first I thought it was a leaking injector. Next thing I will do is change the spark plugs and run through the vacuum hoses with soap water or braking cleaning spray. Somehow I just don't think that is what's wrong...

Is there a valve somewhere that shuts down for the air when the engine is cold (like the carb. versions does)?

I have made 4 videos of the issue.

Cold start:
Idle 2 mins after start:
Idle after 2 km. of driving:
When fully warm:

Rgds.

Heinrich

My thought is that during warm up she is running too low in revs. That should be raised by the aux air valve that might be defective, dirty or up for adjustment. It is located under the intake manifold close to the firewall. You either have an electrical version or a mechanical, by the looks of it you have the electrical version that is also the most sensitive one. Check if it is powered, if so, remove it, clean it up, check if it works when 12V is applied. If it works, you may need to readjust, otherwise replace.

Other views welcome though!

Will try and undo that later for a check. Have been using the car at work today. Had many start/stops and the issue now allso occurs when engine is warm. It's "bumping" and not running clear. When going 2. gear about 1500-2000 rpm. it is "jumping" like you put your foot up and down the throttle very fast. Hope that new plugs would help...

And a check on hoses and intake gaskets for vacuum leaks!

Nobody else who ever had any trouble with similar idle issues?

Update:

Trying to search for vacuum leaks with "diesel start". No reaction.

Tried to disconnect the AUX (if thats the one on the pics with a blue connector you refer to?). It does something as it reacted by running very bad when cold. Put the connector on again and it ran fine again, but only for 2 mins. Then bad idle again untill warm. Now you mention the thing with the cold start rpm. You do have a point. Sometimes the rpm comes up, sometimes it don't. When it does it is usually after 2-3 min. of running and only for about 1 min.

Think I'll replace the unit at once unless it is easy to clean and adjust?

As far as I can see that's the cold start (extra) injector. If it still influences how the car is running when warm it may be an issue as well, leaking fuel inside the intake, of injecting when it shouldn't anymore (defective thermo time switch). You can remove it to check but make sure to have a new gasket for it first. And you can first measure if it is switched measuring power at the connector, that doesn't require removal of the injector.

But the aux air valve is closer to the firewall. The electrical version looks like this:

Anyone who has removed this valve without taking the whole engine out of the car ?

It is fitted with two M6 bolts turning downwards. The one closest to you is no problem but the one closest to the engine seems impossible to undo. At least unless you remove most of the left side components or take the intake manifold off.

Give me a hint and I'll buy you the biggest draft you ever had at the next Sharknose meeting

From the underside it is possible.
You can also try to remove the ignitioncoil and the rubber between the intake and fueldevider to give you some extra space.

It is not easy to turn loose indeed. That's why a lott of people only put the front bolt back when they changed the airvalve. Make sure the airvalve makes maximum contact with the engine because the temperature from the engine has positive influence to the closing/opening of the valve.

Thanks a lot Peter!

Think I'll start by giving it a try from underneeth.

Will update soon...

Well, time for an update

It showed that the ignition timing was too low. After adjustment it idles just nice and smooth.

I allso changes the AUX valve and it works as it should now.

But I still have troubles with the idle rpm. If I stop the engine (from normal temperature) and start it again after a few mins it runs with about 1000 rpm. and stays there till I hit the gas.

It allso drops very low then I release the throttle?

Any ideas what I have missed here?

http://m.youtube.com/watch?v=RwcqaRjYOA ... load_owner

Where's your CO at currently? My guess would be lowish...