Car revving up to 3000rpm on its own

chris_john_lane

I have a 99 vw Golf. I was driving it today and after a few minutes driving it just shot up to 3000rpm by itself. I was driving slow and only in second gear. I stopped the car and it stayed the same until I had to turn the engine off by the key. While stopped I tried revving the engine the revs went up a bit but came back down to 3000rpm. This has happened a couple of times and it struggles to start back up again but always starts eventually. Help?! Thanks..

The Hill Billy

Better suited to Motors than DCN. Moved.

tHB

gavman1

chris_john_lane wrote: »

I have a 99 vw Golf. I was driving it today and after a few minutes driving it just shot up to 3000rpm by itself. I was driving slow and only in second gear. I stopped the car and it stayed the same until I had to turn the engine off by the key. While stopped I tried revving the engine the revs went up a bit but came back down to 3000rpm. This has happened a couple of times and it struggles to start back up again but always starts eventually. Help?! Thanks..

You dont say weather its petrol or deisel but if its a tdi I would say thrres oil getting past the turbo oil seals into the cylinders and its burning it up.should be smokey aswell if thats the case.

JBokeh

Neighbour had something similar , but I don't think it went as high as 3000rpm, it was more like 2500, and only when cold. Turned out to be the coolant temp sensor in it

chris_john_lane

It's a 1.6 litre petrol. Today I was stopped at a traffic light and it just stalled. Took a while to get it started again. Also there is no smoke. Always happens when engine is cold

gavman1

Iac valve could be sticking (IDLE AIR CONTROL VALVE).if it is then its quite an easy fix.im not to familiar with the petrol golfs but its basicly just a case of locating the valve on the air intake and removing the cover and lubracating the valve ifself.they kinda look like a little cylinder that turns as the engine heats up and leans out the air/fuel mixture as it does so.this would also explain the slightly worst mpg as the mixture is staying to rich and will eventually flood the engine hence it cutting out.

Bolomaster

Check out the throttle body as well - could be opening further than normal to compensate for a sticky valve.

exaisle

If the above suggestions don't work, hook it up to VAGCOM on the offchance that theres a faulty sensor somewhere...

gavman1

Iac valve could be sticking (IDLE AIR CONTROL VALVE).if it is then its quite an easy fix.im not to familiar with the petrol golfs but its basicly just a case of locating the valve on the air intake and removing the cover and lubracating the valve ifself.they kinda look like a little cylinder that turns as the engine heats up and leans out the air/fuel mixture as it does so.this would also explain the slightly worst mpg as the mixture is staying to rich and will eventually flood the engine hence it cutting out.

gavman1

gavman1 wrote: »

Iac valve could be sticking (IDLE AIR CONTROL VALVE).if it is then its quite an easy fix.im not to familiar with the petrol golfs but its basicly just a case of locating the valve on the air intake and removing the cover and lubracating the valve ifself.they kinda look like a little cylinder that turns as the engine heats up and leans out the air/fuel mixture as it does so.this would also explain the slightly worst mpg as the mixture is staying to rich and will eventually flood the engine hence it cutting out.

Dont know how this popped beck up again.gremlins at work me thinks.

chris_john_lane

I'm no expert on cars so will just bring it to a garage!!