Gremlins have made it down under -

[PK]

Well, you guys and gals will be pleased to know that you don't have exclusive rights to the VX engine gremlins.

After 3 years of faultless service, my beast has developed the engine idle gremlin.

Started out as an occasional increase in RPM when stopped at traffic lights etc, but quickly became a stall everytime the throttle is released.
Cleaned MAF sensor. Looks good.
Cleaned TPS. Looks good.
Cleaned IACV. It was very gunked up and took a lot of cleaning.

Conditions changed to a running rough at idle when cold, and occasional stall when hot.
Fitted new IACV.
Now will not idle at any time. Stalls immediately the revs drop below 1000 RPM.
I think the new IACV was the wrong one. Same externally, but the poppet valve looked a different shape.
I will swap them back over at the week end and see what happens.

Then noticed a hissing noise coming from the right hand side of the motor as you sit in the vehicle.
The only code thrown is P1404 which I think is the EGR valve stuck closed.

So, this weekend I will try and chase down the correct IACV, look at why the EGR is not working, and try and track the hissing noise.
In the meantime, I have got very good at left foot braking and feathering the throttle to about 1100 RPM.

Anyone got a part number for the IACV?? I couldn't find it in the parts list on this site.
Any other suggestions??

Thanks.

PK

[Scott Larson]

Sorry to hear about your gremlin infestation PK. Sooner or later it gets eveybody, or so it seems. Your hissing noise definetly sounds like a vacuum leak, as do the symptoms, I'd start there. Do you have a vacuum gauge? It does make the diagnosis a bit easier...

I'd start looking for cracked or weathered vacuum lines.

[Grif]

Could be a vacuum leak around the intake manifold. Using a stethoscope, a piece of garden hose or some such listening device might help you locate a leak if you poke around with it a bit when the engine is running. Another quick test would be to spray carb cleaner or starting fluid (ether) around the base of the intake manifold while the engine is running at any stable idle. An increase in RPMs would tell you that the spray is near the leak.

[WormGod]

Dunno, I would hold something other than a vacuum leak suspect. Start with the EGR since the CEL leads you there. You start tearing down too much too soon, you might actually create a vac leak related to 171/174. Baby steps.

[circmand]

Could be a vacuum leak around the intake manifold. Using a stethoscope, a piece of garden hose or some such listening device might help you locate a leak if you poke around with it a bit when the engine is running. Another quick test would be to spray carb cleaner or starting fluid (ether) around the base of the intake manifold while the engine is running at any stable idle. An increase in RPMs would tell you that the spray is near the leak.

I would also say vacuum leak. Note if using a hose to hear the leak remember to empty the water out of it first

[nfpgasmask]

Start with the EGR since the CEL leads you there.

x2. EGR problems with the VX are VERY common. I had the exact same set of symptoms and the same code. I replaced the EGR (very easy swap) and I have been problem free since.

Bart

[tom4bren]

Dude - sorry to hear about your gremlin infestation. I'm sure you'll get a handle on it pretty quick. Best of luck.

[Scott Larson]

Dunno, I would hold something other than a vacuum leak suspect. Start with the EGR since the CEL leads you there. You start tearing down too much too soon, you might actually create a vac leak related to 171/174. Baby steps.

Definitely a possibility. I missed that his CEL had lit, a code would indicate it had. Good catch!

[WILLY]

Time for new intake gaskets.

[PK]

Okay, think it is time to put this thread to bed.
Just this week, I finally fixed this issue.
Comon, 4 mths isn't that bad.

The whole rough idle and stalling when hot, and air sucking sound was a faulty EGR valve.
The valve was seized 1/2 open all the time.
When the car tried to idle, it was getting too much exhaust gas, not enough air.
Under power, it was not bypassing enough exhaust and kept throwing a low EGR flow code.
The "sucking" noise I could hear under the bonnet was the large amount of exhaust gas trying to flow through that small bypass tube.

All the other things I tried made no difference.
Now, if I put the old EGR valve back on, problem is back immediately.

Hope this helps someone else.

PK