hesitant vr6 - FIXED - and worse...

[grimmy 0]

I've just bought myself another vr6, and this one just doesn't quite feel right. I'm sure it doesn't feel as quick as my last one, and for the very first touch of the throttle it hesitates. If you rev hard, ease off and then try the throttle again it seems to struggle for a moment, then pick up. Happens in all gears, at any time. Very consistent, and very annoying as it does it through every gear change.

 

Any ideas?

 

Its a 2.9 dizzy as fas as far as i know.

[gezza 0]

possibly coilpack??

 

air block on throttle bodie, fueling issue???

[dinkus 10]

Cam position sensor would be my bet, but you really need to get the old girl on VAG-COM...

[grimmy 0]

Its a dizzy, engine so cant be the coilpak. Just not sure if its actually a 2.9. It feels a bit more sluggish than my last which was deffo a 2.9. But i've only ever seen 2.8's with a dizzy and its missing the plastic cover that says either dohc or 2.8...

 

I'll see if i can get it plugged into vag com tomorrow morning but its a bit doubtful my mechanic will hook her up right there and then. Just wanting some idea's as i have no idea where to start looking.

[dinkus 10]

The engine code will give it away - AAA is the 2.8, ABV is the 2.9

 

I think it's stamped on the engine down on the driver's side by the airbox somewhere, but could be wrong.

[grimmy 0]

The engine code will give it away - AAA is the 2.8, ABV is the 2.9

 

I think it's stamped on the engine down on the driver's side by the airbox somewhere, but could be wrong.

 

I'll have a gander tomorrow, but surely thats quite hard to spot? It all gets a bit snug around the air box. I'm toying with the idea of sticking a k&n on it that i have in the workshop, just for that noise.... :roll: Would be a good excuse to do it.

[CazzaVR 0]

Some VR6 Corrados had a dizzy- 1992-93 models.

 

Could be the MAF, or as Dom says, cps is a good bet too.

[gezza 0]

i thought they was all coilpacks mine is (94) anyway quite simple just look at it!!

[dinkus 10]

The engine code will give it away - AAA is the 2.8, ABV is the 2.9

 

I think it's stamped on the engine down on the driver's side by the airbox somewhere, but could be wrong.

 

I'll have a gander tomorrow, but surely thats quite hard to spot? It all gets a bit snug around the air box. I'm toying with the idea of sticking a k&n on it that i have in the workshop, just for that noise.... :roll: Would be a good excuse to do it.

 

Yup, and I'm not even 100% sure that's where it is :lol:

 

And mine's a dizzy 2.9 VR, they changed over to coilpacks sometime in 94.

[grimmy 0]

And mine's a dizzy 2.9 VR, they changed over to coilpacks sometime in 94.

 

Gotta be 93 i think cos my last vr was a 93 K reg and was coilpack. I only learned that it was the coilpack making it run shite once it had been written off :( All in the past now though :D

[dinkus 10]

Ah well there ya go - I don't think Karmann even know when the change over was because it all depended on what part came out of the big parts bin first :lol:

[Dogzyboy 0]

Interested to hear how you get on with this one as I still having similar problems with my VR.

[grimmy 0]

I just got back from my local vw specialist and he plugged it in to a little hand held fault code reader thing... The only fault it came up with was the Knock Sensor, so going to try replacing that and see what it does. He didn't know where it was on the vr6, or even if it would fix the problem. Anyone shed any more light on this? Will i be able to pick one up from ECP? Or GSF or something?

 

Thanks very much.

[CrazyDave 0]

VR's have two knock sensors. One on each side of the block. Never heard of one failing though, unless the wire or connector gets damaged?

 

The handheld fault readers are a bit basic sometimes, sounds more like cam sensor or MAF to me. The car really needs a drive around to get the fault codes active as Motronic 2.9 doesn't remember them when the ignition is turned off.

 

If you can get to Worcester, I have VAG-COM and would be happy to have a look for you.

[grimmy 0]

I've just been trying to get hold one locally and no-where has them on the shelf, and you're right there are two. I've bought some STP fuel system cleaner to shove in and see if it helps it. It was really bad earlier, when i tried to put my foot down the whole car slowed very heavily, and then suddenly cleared up and shot off again. It seems to have no pattern to it, just randomly it screws up.

 

Worcester is a bit of a trek, but if i can't find any more help locally then i would gladly welcome your help. Thankyou :)

[CazzaVR 0]

Prob worth changing the fuel filter- 10 minute job.

[Dixxy 0]

I'll stick it on VAG COM if your passing through bristol anytime soon.... Soon tell if its cam sensor.

[STORM 2 0]

yep, my money's on the cam sensor, but could be the blue coolant sensor . I would agree that replacing the fuel filter is a worthwhile, easy thing to do

[drunkenmunkey 0]

Your VR6 will still have a coil pack just not a distributor & coil pack combined. If faulty the coil will miss and hesitate when under load [heavy acceleration] as the high tension [HT] circuit comes under more load and shows up weakenness in the coil as more 'spark' is required. Before you go off buying sensors I would definitely check this first, VWs are known for weak coils and in my experience always go.

[grimmy 0]

So a distributor engine still has a coilpack? Now i AM confused, i thought the coilpack was a replacement for a distributor, and was just an improved way of sending the spark to the plugs? How can it have both a dizzy and a coilpack? I'm gonna go have a look under the bonnet.

[dinkus 10]

All engines need a means of generating a spark and there are two main ways to do this.

 

1. Single coil and a distributor

This is the way it's been done since the dawn of time - you have a single coil that generates a spark which is sent along what's called the 'king lead' into the distributor.

 

A distributor is just that - it distributes the spark to each spark plug.

 

Inside the dizzy is a wheel with a point on the edge of it that spins around with the engine. The centre of the wheel is connected to the king lead. In a circle pattern around the edges of the dizzy are the 6 (or 4 or 10 or whatever) connectors that go to your HT leads to each spark plug.

 

The coil and the dizzy are linked together so that the coil generates a spark just at the same time (near enough) as the wheel in the dizzy is reaching one of the connectors to the HT lead. Thus the coil generates a bunch of sparks and the dizzy sends them in order to the spark plugs.

 

2. Coilpack

Later on, the cost of the coils came down significantly, so it was easier to have a pack of coils which replaced the original single coil and distributor. This had the advantage of remove the mechanical distributor which needs maintenance and could be relatively unreliable.

 

The coilpack has six coils in it - each one connected to a different spark plug via the HT leads and each coil fires when it's needed.

 

It's actually a bit more complicated than that, but it gives you the gist of it :)

[drunkenmunkey 0]

All engines need a means of generating a spark and there are two main ways to do this.

 

1. Single coil and a distributor

This is the way it's been done since the dawn of time - you have a single coil that generates a spark which is sent along what's called the 'king lead' into the distributor.

 

A distributor is just that - it distributes the spark to each spark plug.

 

Inside the dizzy is a wheel with a point on the edge of it that spins around with the engine. The centre of the wheel is connected to the king lead. In a circle pattern around the edges of the dizzy are the 6 (or 4 or 10 or whatever) connectors that go to your HT leads to each spark plug.

 

The coil and the dizzy are linked together so that the coil generates a spark just at the same time (near enough) as the wheel in the dizzy is reaching one of the connectors to the HT lead. Thus the coil generates a bunch of sparks and the dizzy sends them in order to the spark plugs.

 

2. Coilpack

Later on, the cost of the coils came down significantly, so it was easier to have a pack of coils which replaced the original single coil and distributor. This had the advantage of remove the mechanical distributor which needs maintenance and could be relatively unreliable.

 

The coilpack has six coils in it - each one connected to a different spark plug via the HT leads and each coil fires when it's needed.

 

It's actually a bit more complicated than that, but it gives you the gist of it

All engines need a means of generating a spark and there are two main ways to do this.

 

1. Single coil and a distributor

This is the way it's been done since the dawn of time - you have a single coil that generates a spark which is sent along what's called the 'king lead' into the distributor.

 

A distributor is just that - it distributes the spark to each spark plug.

 

Inside the dizzy is a wheel with a point on the edge of it that spins around with the engine. The centre of the wheel is connected to the king lead. In a circle pattern around the edges of the dizzy are the 6 (or 4 or 10 or whatever) connectors that go to your HT leads to each spark plug.

 

The coil and the dizzy are linked together so that the coil generates a spark just at the same time (near enough) as the wheel in the dizzy is reaching one of the connectors to the HT lead. Thus the coil generates a bunch of sparks and the dizzy sends them in order to the spark plugs.

 

2. Coilpack

Later on, the cost of the coils came down significantly, so it was easier to have a pack of coils which replaced the original single coil and distributor. This had the advantage of remove the mechanical distributor which needs maintenance and could be relatively unreliable.

 

The coilpack has six coils in it - each one connected to a different spark plug via the HT leads and each coil fires when it's needed.

 

It's actually a bit more complicated than that, but it gives you the gist of it :)

 

What he said :) Good luck with it

[adevr6 0]

had a similar prob on a mk3 vr.new throttle switch and wiring to it solved the lol in acceleration when blipping the go pedal.hope this helps. :D .

[Roger Blassberg 0]

Sorry to be pedantic, Dinkus. The coilpack has three coils each of which is connected to a pair of cylinders. The coils fire in order to both in their pair - one is on the firing stroke, and the other is not but gets a spark anyway. So if one of the coils fails you will drop 2 cylinders.

 

Best wishes

 

RB

[Guest]

And mine's a dizzy 2.9 VR, they changed over to coilpacks sometime in 94.

 

yeah, 93/94 was the face lift as mine is a dizzy version with a late interior etc on a K-plate, but I have seen other K-plate VRs on a dizzy with an early interior.

 

2.9 was definately available on a dizzy anyways...