K1985

iTrader: (1)

Hi!

Just changed my coolant temp sensor after getting a wonky idle and fault 21 when plugging in the black plugs when engine off.

Just been out for a drive after having the battery unplugged for about 20 mins, but prior to going I checked and was still getting the fault 21. Drove for 30 mins, still showing fault.

Symptoms less severe now, revs dropping less frequently and not nearly cutting out as much.

Firstly, how do I reset the ecu / clear the fault codes so I can monitor it over a fee days and see if it returns.


Secondly, is the more likely culprit for a wonky idle the Maf or the IACV?

Glowplug

iTrader: (8)

Here is the reset how to mate.

TonyBurns

iTrader: (3)

What car/model year?

Tony

Glowplug

iTrader: (8)

Stop being so lazy Tony!

You never heard of 'Find more posts by'?

K1985

iTrader: (1)

Lol cheers guys. All reset and showing clear. Anyone know how much I have to drive it before it's safe to give it a bit of welly again?

Nearly got all the little niggles sorted now, just need to get that idle sorted and also get someone to diagnose the rattle from the exhaust end of the turbo. Hoping it's just a crap gasket rather than the turbo itself. Getting an annoying rattle at low revs coming from that area.

Guess I'll clean the iacv and maf next tho

Glowplug

iTrader: (8)

Any time you like mate. Sooner you start 'driving' it, the sooner the ECU will learn for you.

How bad is the idle, 100,50,10rpm??

Are you still running OE up pipe? If yes, then it could be the heatshield rattling on the up-pipe. Or if you have a decat downpipe, it could even be the turbo chimney. Those sort of things always rattle at idle/low revs due to the frequency.

K1985

iTrader: (1)

Ideal- hopefully it's dry tomorrow for some moorland hooliganism.

Sometimes it'll idle at 1100, sometimes at what looks like 500. When I start it from cold, maybe 1500 to 1700.

The main pain is the revs dropping, say when putting the clutch in when coming upto junctions, or reverse parking etc. Seems to get worse when the engine is hot. I changed the CTS today and it seems to have got better, only nearly cutting out once, but still getting the hunting idle.

Not sure what the up-pipe is - is it the pipe that goes from the turbo down and towards the rear of the car? I have no heatshield from the turbo back, nor a turbo chimney, but can see heatshields below the front side of the turbo - could this resonate up thru the turbo?
With a screwdriver on the turbo and ear on it, the noise seems worse at the rear of the turbo, but this could be due to the thickness in the casting. I don't have any problems with it boosting or smoking, it's just annoying me and I'd like the peace of mind.

That reminds me, gotta get a boost gauge-is there much difference in say a HKS one or £130 and an ebay jobby for £20?

Glowplug

iTrader: (8)

Nice.


Yeah, thats pretty annoying and defo needs sorting. Keep you eye on the fault codes, it's bound to be a sensor on it's last legs and it's just a matter of time before it registers.


No, it runs from the headers up to the turbo, the OE item has a heat shield that some times rattles.


I think you are looking down at the headers there. I could resonate making it harder to pin down/

Yeah, very little worse than a rattle you can't find. It's like toothache.


Same as most things mate, you get what you pay for. Look to spend between £40-£50 on a good branded one. Have a look at this thread if you haven't already.

K1985

iTrader: (1)

Before I changed the CTS I was just getting the CTS code, all clear now so will keep an eye on it but will clean the maf and iacv in the mean time.



In that case, I have standard up pipe. There is a heat shield here so I will have a look tomorrow in the light and try to work it out. It's driving me mental with the thought that my turbo is going to fall to bits and end up getting sucked in to the engine haha




Ta Will get buying