Warm Idle & Hesitation Problem

[Kris2012]

Hi all,

I've done loads or searching on here and I can see lots of similar problems, but quite a few posts don't ever include the final fix. So, I'm planning to post my problem and the post the fix when it happens.

The car is fine when it's cold and runs pretty well (bit twitchy, but I can live with that). When the car gets warm it runs fine on longs runs with the revs above 2k at constant throttle. The problem comes around town when warm when the cars becomes really jerky. The throttle is hesitant up until 2k and the car is pretty hard to drive. A idle the revs will sit at around 1k and then drop to 400 and spring back up quickly to 2k. When I go to accelerate away it will stick at low RPMs and be pretty jerky. Another thing I noticed today is that the coolant temp didn't go above 1/4.

So far I've replaced the CTS, cleaned the ISCV and replaced the spark plugs (they had a bit of oil in the recess, but that's for another day). I'm not sure how well I cleaned the ISCV. I only cleaned out the two holes at the top. I didn't take the rubber surround off, but I'm guessing there's nothing to clean under that.

Could this relate to the Lambda sensor or is it something else?

If it was an earth/leak I'd assume it would happen all the time?

Part of me still suspects the CTS because it only happens when warm.

Cheers

Kris

[MatBrown]

CTS would be my first guess too, which one did you change?

[Kris2012]

Ah, as it turns out there are two....are there two?

i changed the one below and to the left of the distributor cap. If you stand at the front of the car looking at the cylinder head it was on the right side of the block attached to the head.

I can't get a pic as I'm off to work for a few days.

[Wobba]

CTS is a white capped plug, not the top brown one, that's temp reading sensor.

I had a similar issue recently.

Check HT leads for damage and try another coilpack.

Check all vacuum pipes to inlet manifold (map sensor etc).

Clean crank sensor.

Check battery terminals are secure.

When it's warm, let the car idle and do it's odd revving thing. Listen very carefully with bonnet open for any eletrical clicking noises from relay box on passenger side in engine bay. Could be relay failing, like I had. would drop revs suddenly then bounce up again like a misfire.

[Kris2012]

Thanks for that. I'll have to check when I get home. I'd say there's a good chance I replaced the wrong one.

Are the sensors the same? I ordered a CTS from GSF and I've put that in the place I described. Where exactly is the CTS located?

Thanks for all the answers.

Kris

[Wobba]

The sensors are not the same.

This is a shitty old pic showing a leaking core plug where the crank sensor is (in case you wanna check that too) but if you see that white plug that is the CTS position in the thermostat housing which is bolted on the side of the cylinder head by five shitty torx bolts. The connecting plug may be black sometimes, but it is the one that connects horizontally into the housing.

http://i174.photobucket.com/albums/w102/barneywobba/Williams%20217/DSC008842.jpg

[Kris2012]

Thanks again.

Ill check when I get home and it isn't raining.

[Kris2012]

I can't get to the car yet, but below is a pic of the box for the new sensor I installed next to the old one I removed:

http://i1230.photobucket.com/albums/ee482/Kris201111/P1000648.jpg

I'm hoping that I replaced the wrong one!

[Kris2012]

Ok,

This is the sensor that I believe to be the CTS. It's the gold one in the pic:

http://i1230.photobucket.com/albums/ee482/Kris201111/P1000787.jpg

I've replaced it and it hasn't made any difference. Is that the correct one?

I also put a new battery in today and when I did I noticed the connections on the positive terminal:

http://i1230.photobucket.com/albums/ee482/Kris201111/P1000786.jpg

What the feck do they all do? That can't be correct.

All advice is really appreciated. I'm learning slowly and hopefully when I have I can help others and spread the load.

You'll also notice the routing of the throttle cable. That can't be correct either!!!

Cheers

[172lover]

Go to your old battery and there should be some connection thing on it,
Take it off and put it on your new battery,

The accelerator cable isn't original so it's too long.

[FATBOY]

hmmm this all points to the part throttle kangarooing thread http://williamsclio.co.uk/forum/showthread.php?35149-Part-throttle-kangarooing

ive got exactly the same problem changed the CTS and still doing the same, got to try the other things on the list now

lambda,dirty injectors,crank sensor,chip,ISCV,vacuum pipe and bad earths?

[Kris2012]

Thanks.

I didn't describe that as well as I could.

I've managed to connect the battery with all of the old connections. I was surprised by the amount of separate spade connectors that were attached to the positive terminal. I'm not sure if that's normal?

The negative terminal just had one connection which seems more normal. I'd guess one of the connections to the +ve terminal is the aftermarket alarm, but apart from that it seems a bit weird.

I'd guessed that the accelerator cable was wrong. I'll get a new one.

Thanks a lot.

[Kris2012]

Thanks FB. I'll try all of those slowly when I get the time.

Does anyone know if the sensor I pictured on the previous page is the CTS?

[FATBOY]

yes! it is

[Kris2012]

JOINED THE KANGAROOING THREAD.