Help!!!!!!!!!firing on 2 cylinders

The car is running ruff, my car is only running on number 3 and 4 cylinder, I'm getting the spark and fuel to one and two yet not running on those cylinders, any idea? Is it also safe to drive the car?

I wouldn't drive it like that, unless it's an emergency (moving it to get it home or to a garage, etc) - you could strain the crank if you run it too fast, and all that unburnt fuel going through cylinders 1 & 2 means that you'll be bore-washing them (petrol washes off the protective oil that is coating the cylinders, leading to excessive bore wear).

Are you 100% sure that you're getting both fuel and a spark? - unless you've got valves which are bent or stuck open, or a hole in the pistons 8O , you must be missing one or the other.

Thanks, Yes the fuel and the spark is getting to 1 and 2 cylinder, do you think the valves are bent or sticking?

Do a compression test on 1 & 2 first.

Cheers
Rajan

Before anything do a compression test.  If very low or zero on any cylinder its a head off job to properly diagnose.

Cheers.

Mk1's nothing but trouble :cry:

lhasa said

Cheers.

Mk1's nothing but trouble :cry:

ALL cars are nothing but trouble, but at least Mk1's are a joy to own and drive, when they are going well…

PS: Did anything notable happen to bring this fault on? - accidental over-revving, new timing belt, filled up at different filling station than usual, etc?

Reved the car hard parked up to see if any blue smoke came out the back, then went rough running.

Any clues?

Hmmm, does sound like a valve problem. Try this before taking it all apart (although you'll probably still have to take it apart, mind):

Remove the spark plugs, and get an assistant to turn the engine over with a 19mm socket on the crank pulley nut, while you shine a torch into each spark-plug hole to see the edges of the valves move in and out as they should. If any of them are dropped (stuck open) or bent, you should be able to see this, especially when compared against cylinders 3 & 4, which are working fine.

Good idea type17, is it possible to push up the valve with a rod from the spark plug hole, if not could I get away with straightening the valve once stripped?

cheers

I once got a lift off someone who's car had been running on 3 cylinders for years.

Not that I think it's a good idea…

Heh, this should be in engines. Problem with putting it here is we'll never find it in a years time if someone comes up with something useful to say.

On second thoughts…

Peter.

lhasa said

Good idea type17, is it possible to push up the valve with a rod from the spark plug hole, if not could I get away with straightening the valve once stripped?

cheers

There'd be no point in pushing the valve back up, if it has dropped, because this means that it has slipped out of its collets, and so the tappet bucket needs to be removed too, for it all to be put back together (replacing any damaged bits too).

Also, if the valve is bent, and you push it back up, you'll damage the (soft, brass) guide in the head, which might not be damaged already.

If any valves are bent, you won't be able to straighten them satisfactorily - replacement is the only option  :cry:

Removed the plugs and cranked over engine from the camshaft nut and noticed that the valves were going up and down as they should do however no compression on 1 or 2.

Anyone knows of recnditioned engines.

Cheers all.

Still could be burnt exhaust valves - did you see the pistons moving?

Did you compression check with the starter?

Need to pop the head off and have a look.

Might be rings, holed pistons, valves not fully seating, burnt valves, broken con rods……

Given up on it crazy, cheers mate.

Now looking for a reconditioned engine, anyone know where to get a good recon?

Lhasa - Although cheap (?500-?600) and tempting, stay away from Volkspares. Heard endless stories of their engines blowing/failing after low mileage and Volkspares then being pain when honouring their warranty. I'd suggest getting one of the VEGE engines http://www.vegeuk.com . Heard many good things, including high build quality and that they are remanufactured to original VW tolerances. Obviously costs more - around ?1000.

Not sure about having the engine rebuilt by a local company. Again, regularly hear of people who have had their engine reconditioned by a local engine builders only to find themselves having problems with it several months down the road. Seems to be a high level of variance in the standard of local engine specialist.

One person who I would thought would could be good to approach about a rebuild is Ian at Wagenwheels. When it comes to MK1s and GTIs, Ian knows his stuff an more importantly is an enthusiatsts as well. He reckend I'd be looking at around ?1000 for a full engine rebuild.

Cheers

What about TSR? They do standard rebuilds as well as performance.

Oh yer - forgot about them, Hairyarse. Think similar price to VEGE engine, reckon they do a good job with all their experience.

TSR engines are our of my buget range, 1700 pounds if far to much.

The VEGE engine looks ok, does the price include vat?

I had this problem when I was restoring mine, the VW specialists I contacted where more interested in building me 200bhp 2.1 litre bored-out monster and thought it was bizarre that I just wanted it reconditioned to standard spec. 8O  I was put off the VEGE ones because they are exchange and I wanted to keep the original, so I eventually got a local machine shop to do the work, although they returned it without the head on so I had to fit that and the timing belt etc myself, scary.

After 3+ years and 15,000 miles it seems to still be running OK.

I think the bill came to @?600-700 including a new conrod, pistons, pressing in some engine mounts and cleaning the inlet manifold from about ? tonne of congealed oil.