Good news!

[mjb]

I finally got round to cleaning my idle control valve this afternoon. Now I know the real reason why turbos have an oil feed to them. It's not to lubricate the turbine as previously thought, it's actually to lubricate the air intake!

Seriously EWW. Firstly the exterior of it was covered with about 1/8" of gunk, quite surprising to find that it's actually metallic yellow in colour, not black. Figured out how to get the clips undone and took it off to find I couldn't see inside. A good cleaning with carb cleaner and the difference was amazing. There's now some big pools of gunk in the middle of the road where I sprayed it (and the hose to the throttle body).

Before I removed it I did fire up the engine with the connector off (using my foot to hold the throttle open a bit) and it's still mis-firing slightly. bah.

After cleaning and re-fitting, WOW! Apart from the slight mis-firing mentioned earlier, it's a much more steady and confident idle. The difference is amazing.

Just one question left - how the hell do I re-clip the ICV to the intake pipe? It took ages (and a hammer/screwdriver combo) to get the thing off but I can't see how I can get it back on again. Luckily the valve itself is lightly held in place by a plastic clip around the main intake pipe, but I'd really like this little metal clip re-attached. Thinking of grabbing a little jubilee clip if I can get a screwdriver in.

On another note, carb cleaner makes a fantastic engine bay cleaner! Much much much better than WD40 on some cloth!

[puggy]

Excellent news mj years ago when i owned a 2.3 granada i used to use
meths a thick piece of card and a little wire brush to clean the engine. Used
to pour the meths on an area set light to it using the card to stop the flames touching
anything vital ,when it had burned out light rub with wire brush and hey presto !! only downside
when i did a particularly thick oily bit lot of smoke and of course cars then had less electronics
ans pipe work

[steve_earwig]

Used to pour the meths on an area set light to it...

You didn't use a scythe to trim your toenails too did you? Sounds increadibly dangerous!

[puggy]

that made me laugh !!

[mjb]

Update: Problem NOT solved It was rough as usual when I fired it up this morning. I'm thinking my injectors need a proper ultrasonic cleaning.

Actually sod the 'proper'. Wonder if an ultrasonic jewelry cleaner would do the trick... How do you get injectors out anyhow?

[Welly]

Fuel rail off, and they push-fit. Ask James if there are any replaceable union nuts, olives, or gaskets on the fuel line? I would hate for you to have a leak after disconnecting the rail.

At high mileages the injectors wear, not sure a 'clean up' will solve the problem?

[teamster1975]

Update: Problem NOT solved It was rough as usual when I fired it up this morning. I'm thinking my injectors need a proper ultrasonic cleaning.

Actually sod the 'proper'. Wonder if an ultrasonic jewelry cleaner would do the trick... How do you get injectors out anyhow?

Have you tried putting some redex through it yet?
I had a quick google & found this http://www.mikeponte.com/volvo/injectors.htm, could be useful?

Edit: This looked quite interesting http://www.volvoclub.org.uk/faq/EngineF ... r_Cleaning
I know it's volvo but the theory must be the same for most fuel injected cars

[jameslxdt]

you can have the injectors tested to see if they need cleaning, most injection specialists can do this for a reasonable charge, though if the running rough is only from cold i would suspect a faulty CTS rather than injector, but to get them out undo the fuel supply pipe and the return pipe, then the 4 injector wires, carefully jiggle out the fuel rail with the injectors from the manifold, there is then a metal retaining clip for each injector, the very carefully pull the injectors out, they are very brittle and break so easily, trust me ive done it twice before, on replacment there are two rubber O-rings for each injector that need changing

[mjb]

The rough running (not that rough, but you can feel gentle sideways lurches when idling) happens at all temperatures. Very occasionally it'll also miss a beat under full throttle acceleration, usually very soon (not immediately) after a gearchange.

The near-stalls happen only when cold.

TBH I'd love to get the injectors tested, but I'm a bit weary about the thought of popping £480 worth of essential car parts in a jiffy bag and entrusting said bag to Royal Mail. Don't suppose you know somewhere I can have them tested/cleaned on a while-you-wait basis?

Any idea where I can find some details on the electrical properties (and location) of the CTS?

[jameslxdt]

the CTS is screwed into the thermostat housing
most injection specialists will test them while you wait, i used a place down the road from where i worked to get injectors tested, they did it while you wait, and i could see the test too if i wanted

[mjb]

I don't remember a sensor round there... Hmm I'll have a look next time the weather ain't sucking so much in a morning. Just managed to find the autodata page on resistances, so I'll give it a check.

How do I find local injection specialists?

[mjb]

MOT within a fortnight, so hopefully I'll be spending money on this problem soon (provided I can get it through the test).

I've got several symptoms going on:
1) It can stall when cold. Not a straight stall - it has problems for a few seconds before dying and pressing the throttle makes no difference at all. The rev counter bounces violently between 0 and about 500rpm during this
2) On cold days it can run VERY roughly after starting. Sounds and feels as if it's only firing on 3 cylinders. Often leads to a stall if I don't let the engine warm up.
3) Idle is ALWAYS rough regardless of temperature. Well, not rough really as the rev counter's fairly solid, but I can feel a distinct but mild sideways rocking when under about 1500rpm.
4) Lack of power. Top end's down to indicated 120mph (on the autobahn of course) from 140mph last summer (again, tested on the autobahn) and acceleration's not what it used to be.
5) Occasional deadness under heavy acceleration soon after changing gear. Turbo's still spinning, accelerating well then dead for a second, then back on the pace. Quite violent that one, you really know when it's happened.

Dunno if it's ignition or fueling. Thoughts? I'm still inclined to blame the injectors, especially the one furthest from the belt, which always had a nasty loud tick to it. There's no substance to that accusation though.

[jameslxdt]

coolant sensor, put a multimeter on it it, not sure of the exact values but something like 60 - 160 ohms at ambient temp is ok

[mjb]

Can it really have such a substantial effect on the running?

[jameslxdt]

if its open circuit