Poor idle quality - Help & advice please.

[Rusty]

Just looking at compression testers. Draper one looks to be pretty good value and has a longer reach to get down the holes!

http://www.ebay.co.uk/itm/Draper-374...0f82bf3&_uhb=1

[stocious]

Throttle body cleaning time?

[mcandmar]

Just looking at compression testers. Draper one looks to be pretty good value and has a longer reach to get down the holes!

http://www.ebay.co.uk/itm/Draper-374...0f82bf3&_uhb=1

Thats the one i have and its pretty ****** to be honest, where the hose connects to the brass shaft it was glued and crimped, needless to say the glue let go and the hose came off leaving the brass bit down inside the spark plug hole. I manged to fix it but have to be careful unscrewing it, i wouldn't recommend it at all.

[SteveH]

Just looking at compression testers. Draper one looks to be pretty good value and has a longer reach to get down the holes!

http://www.ebay.co.uk/itm/Draper-374...0f82bf3&_uhb=1

Andy, I have one you can use m8. I've not checked mine since getting the car back on the road, so it would be good to get them done together.

[SteveH]

I had a crap idle on and off a few weeks back. Found the culprit, I'd forgotten to tighten up the positive terminal on the battery after disconnecting to do some welding

Worth checking the obvious and easily overlooked first....

[Rusty]

You about this weekend?

[SteveH]

You about this weekend?

No m8, will be skiing and drinking from Thursday to Tuesday

I can leave the compression tester with Rowan if you want to come over and pick it up.

[AndyP]

Thats the one i have and its pretty ****** to be honest, where the hose connects to the brass shaft it was glued and crimped, needless to say the glue let go and the hose came off leaving the brass bit down inside the spark plug hole. I manged to fix it but have to be careful unscrewing it, i wouldn't recommend it at all.

I've also got the same one and although it has been trouble free, it is always a bit worrying trying to unscrew the adaptor by twisting the rubber hose.

I guess you could make an adaptor from an old spark plug and a length of steel tube?

[Rusty]

There is an extender that you can buy.

[UrS4boy]

There is an extender that you can buy.

I am sure your wife/girlfriend will appreciate it too.

[Rusty]

The idle on the missus's Clio 172 is pretty poor but that's down to it being French... ...

[Thecrispynoodle]

I have a recurring 561 code also. I would describe the idle as 'sticky' rather than erratic - sometimes it takes a few seconds to drop the last 200-300 rpm down to a stable position. Once it's there, it's stable but the 561 still gets thrown regularly. I have replaced (all with new and in order)
PVC check valve and connecting hoses
O2 sensor
Spark plugs (Bosch copper tri-electrode)
TPS
Fitted honeycomb screen pre-MAF (previously had been running with no screens at all)
Fuel Pressure Regulator
Inlet manifold to FPR/ECU/vacuum reservoir hoses
ISV

No boost / vacuum leaks evident, ecu claims 0.5-0.6 bar at MAP at warm idle. Car is running TFSi coils on stock ECU. I think the problem predates the ignition conversion.

I suspect I have more than 1 thing contributing to the problem, as both the TPS and refitting a MAF screen made a noticeable improvement, everything else made none. The switch on the old TPS tested out fine, but when driving and decelerating you could feel the engine bucking as the ecu kept swapping maps so it was definitely not providing a reliable signal. I have a new pressure regulator and flame deflector in the post in case it's still breather system related, but can't help feeling I'm slowly ruling things out without getting much closer to the culprit. I think it is idling rich rather than lean based on the amount of water in the exhaust evident in recent cold weather, so maybe injectors are the next thing to check. Can they fail in such a way as to leak fuel as well as the seals allowing air in?

[s2driveruk]

check coolant temp sensor on back of the head too....distant memory of mine causing grief resulting in poor idle G62 IIRC

Maf and ISV contact pins clean?

Its a pain when its not obvious for sure

[s2driveruk]

..actually injector clean and flow testing is a really good call actually. Quick to turn around too. There was a reasonable variation in pattern and cc on mine when i did them a while back

[europeanme]

from what I remember, and it was 2am after all, that the TPS was checked for its outputs with an AVO and with only the slightest Tweek" it would knock the idle all over the place but once it was set to the correct position on the TB it has been fine since....(for a BB turbo that is! )

I cannot remember the figures required, can anyone else help with these...

Good luck..................