16v Engine problems

Hi all

I've got a 1991 VW Golf GTI Mk2 16v and it's developed a some issues that are perplexing me and my mechanic. Both started a day apart (on the way back from passing the MOT obv!)

1. Slight intermittent power loss when hot this is accompanied by rev counter needle jumping up to 4k RPM when the engine's running at a much lower speed (an artificial reading). The oil light has come on at this point too.

2. Loss of idle - the engine's running fine, but is not able to idle, it just cuts out. We've checked the hoses and the microswitch on the throttle controller and all looks fine.

Any help or advice gratefully received!

Cheers!
Mike

 

id be thinking hall sender

 

Cheers fella! Will check it out

 

hall sender for the cut above 4000rpm.
for your other issue check following:
vacuum leak
idle switch switches between open/closed circuit when operated
Idle stabilisation valve is operating (buzzes with ignition on) and clean (soak in petrol/carb cleaner)
Mass air meter flap is not catching in the meter bore

 

Cheers Tom. My mechanic's gonna start by checking the Idle Control Valve and cleaning it if stuck closed for issue 2.

I'll ask him to change the Hall Sender issue 1 - he seems to think a Hall Sender issue would mean a complete engine cut out, but yours and other suggestions mean it'll be worth changing anyway.

Thanks again - is a big help!

 

Hi Tom

The Idle Stabilisation Valve is fine and there don't appear to be any vacuum leaks.

When you say 'Mass air meter flap is not catching in the meter bore' are you referring to the mass air flow sensor?

It's a K-Jetronic engine btw

Cheers,
Mike

 

Can anybody help???
driving me crazy, new genuine ISV, new temp senders and 3 spare controllers!!
Issue is the car starts, idles and drives perfect when cold, sites idling at 900rpm for 3 to 5 minutes then just like some one has turned a switch it suddenly idles like a dog at 300rpm. let it cool down and it does it again, and again. i did find a small pipe disconnected under the air filter, pushed it back and the car was fine for a few weeks, now its doing it again.
its a 87 16V mk2 by the way.
cheers
Mark