Hi all,

I've had this issue for some time now and I've just not been able to fix it.

Basically, when driving (ie the engine is under load) the revs will suddenly drop by a few hundred then return again a second or two later, this can happen every 10 to 20 seconds and you can feel it if you are accellerating.

I have been able to reproduce this while the car is standing by turning on the air con, (although the fault does happen without the air con when driving) and have noticed a load click/clunk just before the revs drop, and just before they rise again.

I've made a short video to demonstrate the issue and wondered if anyone has any ideas as to what this might be. I've also tried disconnecting the MAF in case that was faulty, but apart from running a little lumpy, the fault was identical.

http://youtu.be/J0g1QOziSfw

I've also checked for engine codes - none, apart from when I disconnected the MAF of course.

If you could take a minute to watch the video, I would appreciate it, many thanks.

Andy.

have you changed the fuel filter its agood place to start on the 1.8

No I havent, I changed the coil pack - no difference.

If there's a chance the fuel filter could be doing this, then that can be next on the list - sounds a cheap option to try.

many thanks.

It appears to be a fuel issue though it can be the spark plugs or the leads when was it last serviced

It was serviced back in January, I told them about the issue, but they couldnt reproduce it (I guess because there was no load on the engine).

It's regularly serviced and is low mileage - just over 54000 (was my parents from new).

It was used to pottering about at 30, never saw motorways or long trips, always short journeys.

As soon as I took it down the M4 from Bristol to Kent the water pump went! lol.

hope that background info might be useful.

thanks again.

Short journeys dont do a car any good as they dont get a good run the fuel filter on the 1.8 does cause those issues have you tried injector cleaner and a good blast on the motorway

Not tried injector cleaner, although its had plenty of good blasts down the motorway :-)

I'll get hold of a new fuel filter and some injector cleaner and give that a try, many thanks for the tips.

regards

Andy.