Puma 1.7VCT stalling

perdrix · Post by **perdrix** » Mon Aug 17, 2020 1:20 pm

Engine recently serviced by Chris Allison

.

The car is showing a tendency to stall when not fully warm without the air-con turned on, and when the air-con is turned on the engine stalls whenever it drops to idle.

Chris suggested that I replace the Lambda sensor in the top of the exhaust manifold, and I did that very soon after I got the car back from him.

mmc757 · Post by **mmc757** » Mon Aug 17, 2020 1:34 pm

Start with cleaning, inspecting, and testing the IACV and the hose supplying the IACV.

perdrix · Post by **perdrix** » Tue Aug 25, 2020 2:44 pm

Please advise:

What's an IACV when it's at home?

How to clean inspect and test same?

Wouldn't Chris Allison have done all that when he did the engine service?
Thanks David

DOH · Post by **DOH** » Tue Aug 25, 2020 3:10 pm

Hi David The idle control valve, is what he refers to .
There is plenty of info on this site if you use the search box to assist you with this task.

mmc757 · Post by **mmc757** » Tue Aug 25, 2020 4:56 pm

https://www.youtube.com/results?search_ ... +air+valve

grogee · Post by **grogee** » Tue Aug 25, 2020 6:40 pm

That power steering pressure switch is also known to cause idle problems. From memory it's at the front of the car, right hand side, at the bottom. You'll need to raise the car to see it.

The wiring is quite exposed and can fail. I think the switch tells ECU to give it more beans when pressure is too low, not certain on that.

Wild E. Coyote · Post by **Wild E. Coyote** » Wed Aug 26, 2020 2:51 pm

Worth checking as well: clutch switch (on top of clutch pedal, tells PCM if clutch was depressed) might be important in this case...

perdrix · Post by **perdrix** » Sat Aug 29, 2020 9:51 am

Should there be O-rings or a gasket to seal the idle control valve to the manifold, or is it just metal to metal?

DOH · Post by **DOH** » Sat Aug 29, 2020 11:56 am

There should be a very thin rubberised black metal gasket between the valve and manifold.

perdrix · Post by **perdrix** » Sat Aug 29, 2020 12:35 pm

hmm there wasn't so I used silicone grease which seems to work for now.

Wild E. Coyote · Post by **Wild E. Coyote** » Sat Aug 29, 2020 3:07 pm

You might as well cut your gasket out of thick paper...

grogee · Post by **grogee** » Mon Aug 31, 2020 9:20 am

Yep I've bought some gasket paper which I use for things like this but to be honest it's barely any different to a cornflakes packet!

perdrix · Post by **perdrix** » Mon Aug 31, 2020 9:52 am

Being a bit OCD, I ordered the "official" Ford gasket from an eBay vendor who seems to be a Ford agent (rates-ford) who also sells parts on eBay:

http[url]s://www.ebay.co.uk/itm/272380235606[/url]

David

perdrix · Post by **perdrix** » Mon Aug 31, 2020 9:53 am

I meant: https://www.ebay.co.uk/itm/272380235606

perdrix · Post by **perdrix** » Sat Sep 26, 2020 12:58 pm

Hmmm... I thoroughly cleaned the Idle Control Valve with carb. cleaner, and checked for correct operation with a bench power supply. Now re-fitted with the correct gasket.

It's now back in the car, but it continues to stall on overrun - does the clutch switch tell it to give it more "beans" when the clutch is depressed?

perdrix · Post by **perdrix** » Sat Sep 26, 2020 1:35 pm

I removed the clutch switch, and tested it. It was working fine, so I've refitted it.

David

perdrix · Post by **perdrix** » Sat Sep 26, 2020 2:36 pm

When pulling up at a junction revs drop to 500 - this is when it's likely to stall. After about ten seconds or so, revs pick up to 750.

Is this still suggesting the IACV? If so I guess I need to replace it, or ...

If so what brands to go for (or to avoid)? There's lots out there: Intermotor, Kerr Nelson, Lemark, Lucas etc. etc.

David

YOG · Post by **YOG** » Sat Sep 26, 2020 3:09 pm

Have you checked this Air Blanking Plug? They sometimes split, or fall off:

perdrix · Post by **perdrix** » Sun Sep 27, 2020 12:13 pm

I'll check that today.

Any thoughts on brands of Idle Control Valve?

David

perdrix · Post by **perdrix** » Tue Oct 06, 2020 9:21 am

OK guys, I replaced the Idle Control Valve. Car no longer stalls

But when I pull up at a junction the idle initially sits around 1700rpm for about 20 secs (guessing) and only then drops to 750 or so.

Any ideas of how to fix, or should I just call this a day?

David

DOH · Post by **DOH** » Tue Oct 06, 2020 9:36 am

Hi David This high idle problem has been discussed on the forum in detail previously . Try typing the key words into the search box .
If you draw a blank I will tie up time searching for it for you .

Off the top of my head though .
1)check the butterfly flap on the throttle body as carbon accumulation can cause it to stick when you release the throttle use carb cleaner and kitchen towels.
2) check the contacts to the throttle position sensor (TPS)on the end of the spindle are clean , spray them with electrical contact cleaner and the plug.
3) Check that all the bolts on both the inlet manifold joint and also to the head are tight .
As an airleak can cause this and check all air hoses and the rubber grommet joint at the servo

perdrix · Post by **perdrix** » Wed Oct 07, 2020 1:56 pm

A battery disconnect reset of the ECU solved all - idle now behaving all the time.

Thanks to everyone for their help.
David

Post by **red** » Wed Oct 07, 2020 3:55 pm

I bet that you are glad you persisted

perdrix · Post by **perdrix** » Wed Oct 07, 2020 4:52 pm

You bet!

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