VR6 cutting out and misfires

[Ady_G 0]

My 92 VR6 has started suffering from an intermitant misfire and loss of power. It's only started doing it today, but on steady acceleration it sometimes splutters losing revs, and on one occasion caused to car to grind to a halt with total lack of power. It was like a negative power thing where pressing down on the accelerator actually caused the car to slow down.

 

Experience with previous other cars (Vauxhall SRis etc) makes me think that it's distributer and rotor arm related, the HT leads were replaced last year with standard ones and the spark plugs were replaced in the 12 month service 2 weeks ago.

 

Anyone else had similar problems, or got any easy tests to isolate the problem?

 

Cheers

 

Ady

[corradovr6sc 0]

That happened when my maf failed or could be the cam sensor. Check that the leads are properly clicked onto the plugs.

[Ady_G 0]

Yeah I will check all the connections. I might take it back to my local independant specialist and get them to plug it into the computer and see if they come up with anything.

 

It's one of those annoying intermitant things though, let my dad have a go in it to see what he thought, and it was ok then.

 

Cheers

 

Ady

[crazymarcel 0]

I had a intermitant misfire/ down on power for about a month, before i realised garage hadent pushed the ht lead on properly, wished i had checked that before i bought some more. :(

 

I would change the cap and rotor arm for cheapish piece of mind.

[Ady_G 0]

I just been out for a test drive this evening and it seemed ok, but the cap and rotor arm don't look in the best of condition so I will change them anyway I reckon.

 

I could believe it would be something like an HT lead not connected on properly as it was serviced very recently and I'm still waiting for a rear number plate bulb cover that the garage some how managed to lose, so their apprentice probably didn't do a very good job else where.

 

Think I need a new garage!

 

Cheers

 

Ady

[Ady_G 0]

The car ground to a halt on Saturday and had to be towed home. The distributer and rotar arm where replaced but same problem.

 

When accelerating even very gently there is no power and the car wont move, it's more likely to happen when the engines warmed up, but it's not like an electrical missfire as the engine still runs, it just wont pull. The bloke who recovered it reckoned it was ignition related, the garage isn't sure whats wrong with it and at the moment aren't sure what to do.

 

I'm having to drive the girlfriend's Rover 214 and it isn't much fun as you can imagine.

 

Depressed and going to the fridge for beer,

 

Ady

[Kevin Bacon 5]

If it won't accelerate, sounds like fuel starvation (dead/dying pump) or perhaps the cat has gone into meltdown and is blocking the exhaust? Although that's usually only in extreme cases of over-fuelling over a long time.

 

Also get it scanned on VAG-COM or similar if you can.

[Ady_G 0]

The garage it's at is a VW Audi specialist with all the kit so I'm not quite sure why they haven't located the problem.

 

A few other people have suggested the cat, or a blocked fuel filter. I would have thought any faults like that would show up if they are plugging it in to the VAG-COM thing. When my dads Audi A4s cat went it wouldn't accelerate above 3000 rpm, when mine loses power it wont go above tick over.

 

Cheers

 

Ady

[Roger Blassberg 0]

On a similar line of thought; I once had a back box baffle come adrift and it blocked the exhaust flow almost completely but intermittently, with similar results to those that you report.

 

Best wishes

 

RB

[Ady_G 0]

Thats the sort of thing I bet the garage wont bother checking either, they will be messing round checking sensors and don't bother checking for a blocked exhaust.

 

I hope it is something that simple.

 

Cheers

 

Ady

[Ady_G 0]

The car came back from the garage today with a new set of HT leads on it, they gave me back the old ones, 2 of which had failed with splits in the insulation around the plug end.

 

I just driven it and it seems fine, in fact fantastic after driving a Rover 214 for 2 days.

 

But the HT leads were standard replacement items from Eurocar Parts and had only covered about 12k miles over 2 years. That seems a bit of a short life for a set of leads.

 

Cheers

 

Ady