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Discussion Starter · #1 ·
Hello,
Apologies if this is posted in the wrong forum! My van is a 1995 petrol 2.0 (engine code AAC), I believe it has Digifant electronic ignition. It is running normally except it has started to stall when slowing down. There is no rev counter (I really should fit one) but the revs seem to drop too low, for example when stopping at a roundabout. When idling it is ok, the problem seems to be when there is a drop from running engine speed to slowly down. I wonder if a sensor needs replacing / cleaning?

Any ideas anyone...?:)

Many thanks!
 

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Have mine in the shop for a similar problem, they first suspected a leak in the fuel pump, but then had to replace the whole thing, due to low pressure, this is the 2nd time (another Caravelle) that I have had to repolace one, so I assume its not that uncommon, unless relativily expensive repairs just follow me around.. Get your fuel pressure checked...

Oz
 

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Are you sure that the mechanical settings around throttle barrel are ok. Perhaps tick-over is too slow even when warm, possibility that throttle cable has moved/settled giving more slack, has throttle stop screw moved?
I also believe that there is a bypass for the butterfly so that might want a clean.
 

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Discussion Starter · #6 ·
Thanks all. A couple of years ago she kept stalling constantly when slowing down, turned out injector wiring was shorting out and flooding the engine, took VW garage hours to discover the problem. I don't think this is the same fault as she does idle. I will check all the above. Thanks for all the advice!
 

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Idle control valves are troublesome on these.If it stalls coming up to a junction or on corners it may need replacing or cleaning out with carb cleaner.
Yes, I would second that..had a similar problem and cured it by taking off and cleaning with carb cleaner..been ok since:)
 

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T4 Nelly

I have same problem, but I have read somewhere that in first gear on level van should creep without stalling if ISV ok.

Mine does, so have eliminated this for now. Some pictures on this forum somewhere regarding location.

My local garage has checked fuel press and everything else I have done and said ok, been hooked up to bosch machine and tested fine.

Keeping garages fuel press gauge hooked up to view whilst driving to eliminate fuel starvation if fault occurs again (can drive 200 miles without a murmur!!) got new coil ready to fit as a precaution but one thing at a time!

Been told van should still run even with bad ISV! but may remove at some point anyway and clean.
 

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T4Nelly

Just fitted a new Coil yesterday and gave it a 2hour run with the hammer down, roundabouts and traffic lights ok, ran and idled fine, hope that is the end of my problems.

Coil is a known weak point and not difficult to fit so worth having as a spare anyway.
 

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Discussion Starter · #15 ·
Interesting, I wouldn't have thought of checking the coil as it runs fine, apart from the stalling when slowing down! Seems like it could be a few causes according to people's advice... Maybe I should check the fuel pressure, still wonder if it's a sensor as engine has always dropped the revs and raised the revs itself to prevent stalling. Until now!
 

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Have you changed the small bore vac pipes from the inlet manifold to the fuel pressure regulator and ECU yet? Stalling on the overrun is the classic symptom of perished/broken vac pipes.
 

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T4 2 Ltr AAC one of the first RHD off the production line 1991
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I feel your pain, have had the same problem for months!!!! same engine

Try disconnecting the ISV (silver cylinder on top of the manifold with a 3 pin plug and 2 pipes), the engine may then tick over, try plugging back in and see what happens, on mine you can hear the valve open and then the engine stalls. VAG Com showed air leak. if the valve is working, you should feel buzzing with the ignition on and not started. if the Valve is working but still stalling try unplugging the Throttle Position Sensor (TPS) small black sensor on the top of the throttle body, if the problem stops try measuring across the two outside terminals in the switch with an ohmeter they should be around 1.5 Ohms, the plug on the wiring loom should measure 5 volts on the two out side pins, also measure down to earth and wiggle the loom, the cables do sometimes break.

hope this helps, I have got so frustrated with this as it can be so many different things.

cheers
 

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Discussion Starter · #19 ·
Hi all, thanks for your suggestions I will try them asap, my van is a motorhome so stored away from home. I planned to investigate stalling on Monday but found water was getting in and wrecking the wooden floor so I spent about 8 hours trying to re-seal it. Hope it works as water ingress can cost thousands to fix if left. :eek:

Thanks again everyone, much appreciated. I'll let you know if any of the above sort it out!
 
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