vw golf 1.9 dsl problem

aidhan

I have a '99 golf dsl non turbo 1y code. running very bad, cutting out, spitting back through inlet manifold. misfiring etc. However when the vacuum pipe is disconnected from the E.R.V. valve it runs much better but still wont pass 3000 rpm. It seems when the vacuum pipe is connected the E.R.V valve remains fully open ans smothers the engine I have replaced the valve and also a small plastic valve thats connected via a vacuum pipe to the E.R.V. valve. What controlls the E.R.V. valve? Anyone any idea's?

Stoolbend

Could your exhaust be blocked?

aidhan

barry81 wrote: »

Could your exhaust be blocked?

Good question but exhaust is actually smoking quite bad when the engine runs bad so it appears to be free. Thanks for your reply.

magher

Usually if a diesel (Or petrol for that matter) won't rev over a certain rpm it points to the MAF as the cause. In VAG cars this is a common problem, and it may not show up as an error light, try and find the maf, disconnect it and see if it runs better

Slidey

The fact that it is making noise through the inlet manifold suggests a timing issue to me.

Have you had a timing belt replaced recently? It could also be something to do with an automatic advance on the pump.

When you say that it won't rev over 3000, is this because it hasn't the power to do so or do you think it is being put into safe mode by the ECU? What I mean by that is, is it stopping bang on 3k or is it up and down what it revs out to?

aidhan

magher wrote: »

Usually if a diesel (Or petrol for that matter) won't rev over a certain rpm it points to the MAF as the cause. In VAG cars this is a common problem, and it may not show up as an error light, try and find the maf, disconnect it and see if it runs better

It doesn't seem to have a M.A.F. as is a non turbo but does run better with the E.R.V. vacuum disconnected.

Slidey

Are you blocking the vacuum pipe or just disconnecting it?

If you are just disconnecting it you may be loosing enough vacuum that it could be affecting some other part

aidhan

Slidey wrote: »

The fact that it is making noise through the inlet manifold suggests a timing issue to me.

Have you had a timing belt replaced recently? It could also be something to do with an automatic advance on the pump.

When you say that it won't rev over 3000, is this because it hasn't the power to do so or do you think it is being put into safe mode by the ECU? What I mean by that is, is it stopping bang on 3k or is it up and down what it revs out to?

Its missing and spitting back through the inlet manifold and after switching off will smoke out the inlet manifold for a while. Once the E.R.V. vacuum is disconnected the misfire goes engine runs smoother but will not rev much beyond 3000 rpm.and has a growly noise. Where is the ECU on these ? The car was perfect until it went through nct where no doubt the sh-te was reved out of it. Valve timing was checked and all marks lining up. Thanks for all your replys.

aidhan

Slidey wrote: »

Are you blocking the vacuum pipe or just disconnecting it?

If you are just disconnecting it you may be loosing enough vacuum that it could be affecting some other part

I was just disconnecting it however i loosened the ERV valve and slid a piece of cardboard down to completely block it and this made no difference either.

Slidey

It is hard to diagnose over the net but I am gonna go with injection timing.

Of course it may have struck a valve when it was reved for the smoke test. A compression test would rule that out if that was the case

voxpop

Is it the EGR (Exhaust gas recirculation) valve your talking about ? If you want to disconnect it, the best way is to just remove the vacuum pipe and stick a golf tee in it. The valve without a vacuum stays closed and doesnt allow exhaust gases back into the inlet to be reburnt. If its jammed open (it would have to be really caked up for this to happen), you may be getting too much exhaust gases mixed back in - accounting for rough running.

It might be worth you while trying to find someone with vag-com and having them scan for error codes - might give a better clue as to what is the issue.

El Guapo!

Slidey wrote: »

It is hard to diagnose over the net but I am gonna go with injection timing.

Of course it may have struck a valve when it was reved for the smoke test. A compression test would rule that out if that was the case

+1
Have to agree with this. I think your best bet is to do a compression test and see what the outcome is.

hiluxman

i would think the egr valve is stuck open with carbon. block the exhaust feed to the valve with a blanking plate instead of a gasket. also a 1y engine code, i dont think it has an ecu.
what colour is the smoke coming out of the exhaust?
if it was an inlet valve stuck open it would be very obvious pop from the inlet manifold

aidhan

barry81 wrote: »

Could your exhaust be blocked?

Many thanks for the replies. It was in fact the exhaust that was causing the problem even though it was smoking quite bad and appeared to be free.. I removed the rear section two boxes and it made no difference strangely it was no noisier either. I then removed the front pipe which includes a small box. I reddened this with gas and bate the f**k out of it and a rake of stuff eventually came out the manifold side in all about the size of five small boxes of matches. Golf is going better than ever now. I would say it was semi restricted for a long time.

voxpop

aidhan wrote: »

I reddened this with gas and bate the f**k out of it

precision engineering at its finest

shamwari

I've seen similar before and the exhaust blockage was caused by a catalytic converter breaking up. However I don't know if that vintage of VW Golf has a cat or not..