Hi guys just new to this, I've just bought an XJ6 sport 1996, lovely car however after the engine is at normal temperature and the choke has switched off most times when i get stopped at a give way, lights or roundabout the engine cuts out. it seems to idle at around 6-7000 rpm after the choke switches off and this is when my problems begin. it always starts back up no problem but i feel i must get this fixed asap, is this a common fault and is it to do with the idle control valve? is it an easy strip out and clean to end this issue or will this be an ongoing fight against this until a new unit is fitted.
cheers Paul thanks for your input

 

In the absence of anyone more expert I seem to recall that others suggest that an unmetered air leak can cause this. Maybe check the various bellows and breathers for leaks? Not sure there's a choke on this car, I think you mean once it's warmed up?

I assume you mean it idles at 600-700 (not thousands) which is roughly what mine does and I don't believe this is a common problem although it does seem to crop up.

I hope someone more expert will be along shortly.

Mike

 

Drmike is correct to assert that there is no "choke" on that car. And, an "un-metered air leak" could be an issue. There are a variety of things that could be suspect. 1) Like suggested already, checking bellows, etc. for leaks is never a bad thing. There also was a bulletin that prompted fitting an oil breather on the hose coming off of the valve cover down through the intake on the drivers side. These were prone to separate and leak over time resulting in a vacuum leak. 2) These throttles were prone to sticking. The way to check them is (with the engine off) twist the throttle wide open and let it slam shut by releasing it (with your hand, under the hood). When it slams shut you should be able to open it back up with no resistance. Any resistance points to build up in the housing which could result in starving the engine of air causing a dying issue. Its simple enough to remove and clean the throttle housing thoroughly. 3) Iv'e seen coils go bad but not bad enough to set an engine light. 96 models were coil over and not plug wires. I would make for sure you do not have a coil going bad that is causing a stalling issue. Sometimes you can feel a slight misfire from the engine when stopped, if you pay attention. 4) I have seen TPS sensors go bad as well but not very many IAC motors. Before condemning one of them I would move through steps 1 through 3.
Hope that gives you a starting point.

Cheers,
Chris

 

There we go I knew someone more expert would toddle along

 

Cheers guys, will follow your steps and hopefully a simple fix
Thanks

 

I agree.

The "black goo" that builds up around the throttle disc and the inner bore of the throttle body will reek havoc with hot idle.

Mine was caked on the throttle bore, and I had to CAREFULLY use a scraper to get it out, followed with a solvent (petrol will do) soaked rag to wipe, wipe, wipe until all cleaned up.

I then opted to change the oil filter from the top, so the trunking is removed, and I simply wipe that throttle body out at each oil change, and it is now NEVER messy, just a small thin film sometimes.

 

I hadn't thought of cleaning that while the MAF was off for the oil change. What a sensible thing to do.

 

Aussie invention, ha.