Further to my vacuum pipe question.

[kingsgate]

Brian4 has answered hwere the pipe goes so that question is dealt with but I'm not sure about the CCV, car has done 105K and has not been maintained well in recent years from what I'm finding. I had the usual air bag light fix to sort out and many other bodges so I'm not sure I'm chasing just genuine faults.

My main issue that's got me checking everything is poor start ups and then very average performance. When I turn the ignition on I get a rapid electrical tick-tick-tick from what I believe to be the ICV, it doesn't make the noise when the engine is ticking over and I can unplug the ICV and get no change in running at tickover, is that correct? When the engne starts it seems okay but very average. On odd ocassions it starts with all guns firing, by that I mean it sounds and responds very differently, the airpump even runs which it doesn't mst of the time but it's not an air pump fault. The car drives much better and MPG is better. This seems to me an electrical fault, could even be the EMU but until I've eliminated other sensors, relays etc I'm reluctant to get another EMU. Even tappet noise is less when the engine is running well, I'm confident the Vanos are oaky.

 

[tower]

had the codes read ? to see what,if anything shows up

 

[kingsgate]

had the codes read ? to see what,if anything shows up

That's the puzzle here, there are no codes showing.

 

[tower]

Like you I would check the vacuum system for leaks,unfortunately also like you I am new to Z3 (owned my 2.2 for less than 6 months)so am still learning also. But just keep at it,you will get there,they are a great bunch on here so advice and help is never far away

 

[zedonist]

If the vacuum system is blocked, the car can never come out of start up ECU map and may explain your average performance, if you have no codes it means there is a mechanical issue which would point to the valve. When you disconnect a vacuum pipe the engine should hunt, which shows the sensors are working, the start up ecu map does not use the sensors.

 

[kingsgate]

If the vacuum system is blocked, the car can never come out of start up ECU map and may explain your average performance, if you have no codes it means there is a mechanical issue which would point to the valve. When you disconnect a vacuum pipe the engine should hunt, which shows the sensors are working, the start up ecu map does not use the sensors.

Thanks for that info, I have a new CCV on order, if I remove the dipstick or the oil filler cap when the engine is running the engine does hunt.

 

[kingsgate]

Well I've replaced the CCV and that has made zero difference to my problems. I've discovered that someone's been in there before me and made a bit of a mess. I've added some photos of my throttle body because as can be seen the throttle when closed doesn't come back to the tickover adjuster. The butterfly closes fully and I can't feel any free play in the spindle etc. Since tickover seems okay I'm wondering if this mechanical error is being compensated for by an electrical adjustment somewhere, could this be part of my start up problem?

Anybody know of any set up tricks for the throttle body?

 

[zedonist]

I would buy a throttle body off ebay and try it, the ccv had a lot of mayonnaise, did you also clean out the dipstick tube, or replace the valve only?

 

[kingsgate]

I would buy a throttle body off ebay and try it, the ccv had a lot of mayonnaise, did you also clean out the dipstick tube, or replace the valve only?

All tubes to the CCV were cleaned though they had hardly any muck in them. Dipstick tube was removed but again had no real muck in it, old CCV was pretty clean inside the tubes so had probably been replaced, pipe to dipstick was an insulated one so probably not original.

 

[kingsgate]

All tubes to the CCV were cleaned though they had hardly any muck in them. Dipstick tube was removed but again had no real muck in it, old CCV was pretty clean inside the tubes so had probably been replaced, pipe to dipstick was an insulated one so probably not original.

Just found an interesting little write up about setting the throttle stop screw which I'll try as soon as I can. Basically you undo the lock nut, turn the stop screw until it contacts the throttle arm then turn it an extra quarter turn then re lock the nut, the ICV should then do the necessary adjustments. I assume there is aTPS as part of the throttle body so it's possible this process will mean that it sends a slightly different reading back to the EMU and air metering will also be different so maybe the start up will improve. I'm familiar with a similar process on older BMW bikes where you adjust the TPS while measuring volts from it, then you can set the throttle bodies with a Mercury vacuum gauge.

 

[David Cullen]

there is a tps, let us know how you get on with this man, interesting ;-)