Rough idle but only sometimes

[Yellowvan]

Strange idling for me was ICV or SCV same part.
To do it properly IDS

[knobby1]

Ok so now that things are quietening down for me over th Christmas I'm now going to get this sorted. I've just spoken to a garage in Darlington who says he doesn't have the IDS but says he can re code the injectors. Could this be right or does it need to be an IDS? I did ask him what equipment he was using but didn't really give me a straight answer

What sort of mileage has your van done??

Unless you've replaced an injector/injectors, re-coding won't help much, can't hurt though...IDS will tell you the injector codes already entered in the PCM, you can check these numbers against the codes/numbers actually printed on the injectors themselves.
We've found pump/pilot learns and PCM update helps the most. If you haven't had the PRV and SCV checked/replaced recently it may be an option....
There are some readers/units other than IDS which can do the learns etc..but IDS can do so much more than just read codes and do a few fuel related things, it can do/change/adjust just about anything required on/in the modules in our Mk7 vans.

I had similar symptoms with my van when I first bought it, only had 27,000kms on it so I didn't think wear would be an issue.... turned out there was a small amount of wear/scoring in the bore and piston of the SCV, it didn't move smoothly and was sticking.... probably due to crud in the fuel, the filter had never been changed from new. The SCV is essentially a voltage dependent sliding solenoid metering valve, it has very fine tolerances.... if there's any wear or scoring on the bore or the piston valve itself...or even a small amount of crud in it...it can stick and play up causing irregular idling etc... clean fuel is a must with this sort of valve...this is why we always recommend the fuel filter be changed regularly.

Guys like Karl, Martyn, Loot, Ake and many others have known this for many years...I've learnt lots...and am still learning lots thanks to these guys. If it wasn't for this forum and the afore mentioned people...I'd still be bending over at my local Ford dealer every time I had an issue. Now I can just plug in my IDS and it will tell me if there's anything amiss...and usually what's causing it. My IDS has paid for itself many times over.

Lord Knobrot

[kylezx7r]

Well looks like I'll be bending over, it's booked into ford this Friday so I'll let you know what they say

[Jason_app]

Hi. Did you resolve this issue. I know yours is a different van but identical symptoms starting.


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[kylezx7r]

Hi. Did you resolve this issue. I know yours is a different van but identical symptoms starting.


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Yes mate it I had to have the EGR valve ands suction control valve replaced.
Not sure what the suction control valve is but someone on here will be able to advise

[Jason_app]

Thanks for replying.

Suction control valve !! Would that be Map sensor ?

Anyone?


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[RustBucket]

No the Suction Control Valve is on the fuel pump. Part of the fuel metering system.

[Jason_app]

Is this a mk7 only thing?


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[knobby1]

Is this a mk7 only thing?

Yes, it's essentially a TDCi "common rail" thing, SCV lives on the fuel pump, basically it's a fuel metering valve...

Mk6 TDDi doesn't have an SCV..

Lord Knobrot

[paulplom]

There's a garage in Newcastle Upon Tyne which does the prv and updates. I have one of their business cards in my van. I can get you the details if you're interested. I'm in my goonie and it's pissing down outside though haha.

[kylezx7r]

There's a garage in Newcastle Upon Tyne which does the prv and updates. I have one of their business cards in my van. I can get you the details if you're interested. I'm in my goonie and it's pissing down outside though haha.

I used Durham diesel services located in beamish. They were greet, a tad pricey perhaps but it was in and out in a day and their customer after care is excellent too.