VR6 with weak idle - check list?

[G-Lad 0]

Hey all

 

My VR has just developed a really weak idle, that now invariably just drops and stalls when I pull up to a junction. Sometimes it puts up a bit of a fight and the revs from fluctuate from sub 500 to 1000rpm, kind of feathering up an down a few times, but more often than not it's just dropping off the dial and leaving me standing. :gag:

 

I'm wondering if my recent foolish near-emptying of the fuel tank has stired up some debris, and a fuel line is partially blocked or something. I know it's still got the original inline filter on the rear, which needs replacing and fitting with proper jubilee clips anyway..

 

It very much reminds me of my Mk2 valver that was refusing to idle, which was cured by a new Idle Stabilisation Valve (cleaning in petrol made no difference - about £110 from GSF iirc, 2 years or so ago). It also kind of feels like my old Renault 5, when it had a blocked carb, again from running the tank dry (back in skint student days).

 

So apart from the fuel filter down by the rear beam, and the ISV, what else should I be checking, please?

 

I could do without visiting Mr Cresswell again if at all possible - I want to get some new tyres on her soon ;)

 

NB: I shoved in some STP fuel injector cleaner about 50 miles ago but no change. Also, I've driven from Nottingham to Sheffield, Stockport, Bradford and back to Nottingham, and it's still doing it - so miles are not helping to clear any obstructions.

 

If I'm sitting at a junction and I've managed to catch the revs before they drop off, occasionally I find it drops off anyway or splutters and fails to rev, as if the fuel is restricted even though I'm applying some throttle. Maybe my imagination, but it feels like fuel is being restricted - but then I guess the ECU could be doing something clever with the fueling...

 

Answers on a postcard please! :brickwall:

 

Cheers

 

 

Chris

 

PS: It's an L reg

[Skills 0]

Had this problem last week. Took it to my local vw specialist who plugged it into vag com. The problem was with the throttle body, they gave it a clean and now it's back to normal.

[G-Lad 0]

Had this problem last week. Took it to my local vw specialist who plugged it into vag com. The problem was with the throttle body, they gave it a clean and now it's back to normal.

 

Nice one, thanks :)

 

Looks like I might be going to C&R then after all!

 

Any more suggestions of basic DIY things I can check / swap / clean?

[dirtytorque 0]

Hi.

VR is not my thing but I think this one comes up quite often so it is worth using the search.

I think i've seen it a few times anyway.

[CazzaVR 0]

Is it worse when cold on start up?

 

Could be the MAF, but my money's on the ISV. Take it off, give it a good soak with carb cleaner. With a flat head screwdriver carefully open the springloaded mech inside to make sure it's not sticking. Check all the ISV pipework to make sure it's connected properly and that the sponge from the damper pot (black plastic box connected to ISV) has not been sucked into one of the pipes. The pipe which connects from the ISV to the back of the throttle body intake hose can often be a little loose and just need pressing back in. Check the ISV wiring for nicks etc.

 

Throttle body is dead easy to clean. Just take off the intake hose and give a good spray with carb cleaner. Make sure you open the butterfly and clean around the edges etc. Cotton buds are handy for the more awkward bits.

[Skills 0]

Well, it WAS back to normal. Just had the same problem on the way home. This time it wouldn't start straight up again though. The engine would start and then die again immediately even if i revved. Was almost like the immobiliser was kicking in. Pushed it to the side of the road and after a couple of mins it was ok again.

With mine it seems to only really be a problem when the engine is warmed up. Today's the first day i've done more than about 15 miles in it since I had the initial problem. Thinking back it was only an issue when i'd been on long runs.

 

Any ideas?

 

Tom

[mic_VR 3]

Classic VR problem I'm afraid guys, believe me I spent ages trying to sort similar on mine. Unfortunately depending on how/when the stalling and dodgy idle occurs can mean it's a different broken sensor.

 

Straight stalling when you pull up at a junction, ie no hunting or hesitancy, is usually ISV sticking or faulty.

 

Stalling only when hot/up to temp and having issues restarting can be blue temp sensor not registering the correct temp and keeping the car in warm up/chuck in loads of fuel mode.

 

Hunting/Stalling and lack of power etc can usually be traced to MAF, but others have told me that Lambda problems can have the same symptoms. Difference is that MAF issues don't usually show up on vagcom unfortunately.

 

Also consider checking HT leads and coilpack (if you've got one) and also check for any potential airleaks in the air intake pipe working letting in unmetered air.

 

Now like I said I, and many others, have tried to cure the VR stalling issue and unfortunately it's not an exact science. First I'd vagcom it if possible and then see what/if any error codes come up. It'll also give you a chance to see if the water temp sensors are working correctly. Then have a good search on here as this issue has got loads of thread for it with different tips/tricks to try and cure it.

Hope this helps. Good luck!

[Skills 0]

Thanks for that, from what you're saying mine sounds like the blue temp sensor. Going to order myself one and see if it does the job. Is it an easy job to fit it?

 

Tom

[CazzaVR 0]

5 min job to change the blue sensor. Make sure you buy the correct o-ring to go with it.

 

Locate the stat housing- front right of engine bay, kind of in front/below the coilpack.

 

Unplug the 3 sensors (gives a bit more room).

 

Undo the wire holder that clips on above all 3 sensors- you can prise it up with a flat head screwdriver.

 

Have a piece of cloth, ready to bung the hole in the stat housing once the sensor has been removed. This will stop coolant pouring everywhere!

 

Pull out the blue sensor- may need a bit of a side-to-side wiggle, and immediately bung with the cloth. Get the new one ready, pull the cloth out and push new sensor in.

 

Replace securing clip and plug sensors in. HTH- REALLY simple job!

 

ps- get the sensor from Ford - was over £5 cheaper when I bought one a couple of years ago. It's the same part as the Galaxy VR6.

[8vMatt 1]

Hi guys, i've had this very same problem until today.

 

My fix involved changing all 6 spark plugs and that's all. Problem has gone completely on mine. Not saying this will fix yours as could be something different. Just thought I would share that as it might help. Old plugs were totally knackered. Car was stalling everytime I stopped. All good now.

[G-Lad 0]

Classic VR problem I'm afraid guys, believe me I spent ages trying to sort similar on mine. Unfortunately depending on how/when the stalling and dodgy idle occurs can mean it's a different broken sensor.

(snip)

 

Thanks mic!

 

I'm pretty sure my blue coolant temp sensor was swapped when the thermostat and housing was done approx 2k miles ago. Got new HT leads recently also.

 

Excuse the newbie question, but can you confirm: I'm assuming based on the name, that the MAF (mass air flow) is the widget with the fins inside the air intake pipe, with a wide connector on the outside? When i disconnect with the engine running, it dies almost immediately, suggesting this device is working normally during idle, with the engine dying when it gets disconnected (cutting fuel as no air intake is detected?)..

 

Also, weirdly, the whole problem seemed to have disappeared this weekend, that is until I razzed down the M1 and got the oil up to 120 degrees, after which it stalled once in a traffic jam but immediately restarted and stayed ok for the rest of the day (Northants back to Nottm).

 

It definately seems to only happen when the engine is up to 120 degrees oil temp or beyond, and always restarts straight way (albeit in a puff of unburnt fuel - 0r atleast I hope that's what the smoke is!!).

 

I think my real issue is that the engine runs too hot (110-120 deg at a 70mph cruise in 5th, with recent autobahn speeds getting me to 120 or even 130 if really pushing it). Surely this can't be normal? Coolant very rarely gets over 80 and never over 90 deg since the thermostat, housing, sensors and pipework were totally replaced in March.

 

NB: I'm pretty sure I've burnt my way through 2l of Synta silver 10w 40 in the last 1740 miles.

 

Cheers

 

Chris

[G-Lad 0]

Is it worse when cold on start up?

 

it has only happened a couple of times on cold startup, but it usually happens once the oil temp is high (sometimes at 110, almost guaranteed to stall at 120+).

 

I understand that if happening when warm, the assumption is usually that its the coolant sensor at fault, leading to over fuelling. However if over fueling it shouldn't / wouldn't restart straight away, which mines does. Any thoughts?

 

Could be the MAF, but my money's on the ISV. Take it off, give it a good soak with carb cleaner. With a flat head screwdriver carefully open the springloaded mech inside to make sure it's not sticking. Check all the ISV pipework to make sure it's connected properly and that the sponge from the damper pot (black plastic box connected to ISV) has not been sucked into one of the pipes. The pipe which connects from the ISV to the back of the throttle body intake hose can often be a little loose and just need pressing back in. Check the ISV wiring for nicks etc.

 

is it possible to pop the damper pot apart and clean the innards? I had it off at the weekend but was cautious about forcing it open for fear of cracking the top with the pipework.. It was really filthy inside the pipes, so I'm concerned about what's floating around inside the mesh!

 

Throttle body is dead easy to clean. Just take off the intake hose and give a good spray with carb cleaner. Make sure you open the butterfly and clean around the edges etc. Cotton buds are handy for the more awkward bits.

 

I'm told it'll need re-setting up - is that only if removed for cleaning? Cleaning in situ is ok, yes?

[CazzaVR 0]

You can totally delete the ISV damper pot with no ill effects. Just go to a motor factors and get some hose of the same diameter as the ISV pipework. It's really straight forward.

 

Cleaning the TB in situ is fine :) Obviously, you will be able to do a more thorough job with it off, but it would be more hassle. Would prob benefit from a proper VAGCOM set up, but it should be fine without. Go for it!

[mic_VR 3]

Excuse the newbie question, but can you confirm: I'm assuming based on the name, that the MAF (mass air flow) is the widget with the fins inside the air intake pipe, with a wide connector on the outside?

 

Indeed it is mate. Located on the back of the airbox. Unfortuntely the MAF can be faulty but not actually dead altogether, instead it just doesn't get a full signal. If it's only very intermittant it's worth cleaning it with a quick spray of contact cleaner (maplins) but don't actually touch the wire. Might get it to survive a little longer but again to guarantees I'm afraid.

 

As Cazza has said, damper pot can be removed altogether but if you're having stalling issues it's worth making sure the foam from the damper pot hasn't been sucked into the other pipes, and also the pot itself is prone to splitting as it's subject to quite a bit of heat from the exhaust manifold.

 

Let us know how you get on chap.