Suddenly started chugging!

[greencode]

Just got in my MK3 16v GTI today and went up the road and it started chugging away. As though when I was accelerating something was stopping a smooth acceleration - instead it would go then try to hold back a bit - then go and then hold back a bit. Very annoying as I have a business meeting in London tomorrow so now I've got to get the incredibly expensive train.

Anyway, does anyone know what it could be? I've had it for around a year and this is the first time it's surfaced. I don't know if this was complete coincidence as well but the battery was also flat - I hadn't used it for around a week but I would have thought it'd last longer than that.

I've read a few posts about chugging and some say to replaced the ECU Relay?

Any help or ideas would be very much appreciated.

[greencode]

Umm, thought I'd just nip out in the car again to see if the problem had miraculously disapeared and it has! Obviously, I'm not full of confidence that this won't come back again so any idea or help would still be appreciated.

[Mikester]

Yeah, wouldnt hurt to replace the ecu and fuel pump relays.

Check the vacum hoses on the engine that breath from the top of the block, if they have a split no matter how small they get clogged up with rubbish.

And will then clog up the throttle body.

[greencode]

Any idea which relays are which... My fuse and relay box don't seem to correspond to the Haynes Manual!!!

I've attached an image - each relay has big numbers on - the one's with x are simply blank

[Tuccy]

My girlfriend experienced the same prob with her 8v (soon to be vr6 hehe)

anyhow after a lot of unsuccessful probing for the prob, and with the help of vag com it turned out to be the lamba, when we replaced it the prob disappeared,

it almost felt like the car was dropping a cylinder, no power or acceleration, then it would clear itself for a bit, then reappear again etc etc... Lamba was the culprit...

[nikkim53]

I've also had the same problem and it turns out it was the air flow meter - replaced that and the car is running like a dream.

[greencode]

I've also had the same problem and it turns out it was the air flow meter - replaced that and the car is running like a dream.

So was it really random? For example the car seems to be back to normal now (I haven't driven it much though)?

[nikkim53]

As soon as i bought the car i noticed a slight flat point at 3000 revs but i thought it just needed to be driven 'properly' as it was an old geezer that had it before me, after a couple of weeks i thought i was right as it completely disappeared but a couple of months ago it started again and got worse and worse - to the point my top speed was 63 mph - then like i said i disconnected the air flow meter plug and it was perfect, so replacement as needed !!

[greencode]

As soon as i bought the car i noticed a slight flat point at 3000 revs but i thought it just needed to be driven 'properly' as it was an old geezer that had it before me, after a couple of weeks i thought i was right as it completely disappeared but a couple of months ago it started again and got worse and worse - to the point my top speed was 63 mph - then like i said i disconnected the air flow meter plug and it was perfect, so replacement as needed !!

Thanks for this - not too sure if it's the same issue though. I'm able to accelerate and go fast but it just seems to pull back as it's moving... I've actually just been out to take a look at it now and it won't start - the battery seems to be going dead very quickly just recently!?

[rubjonny]

for relay number/positions check the fusebox faq in zee garage section.  i think you need to get your car onto vag-com!

if you cant then 1st thing I would do is replace the ecu temp sensor with a new one from VAG, its the 2 pin white one. also try unplugging the lambda, if problem goes away you need a new one! crank sensor is also a problem on these, its right down the bottom of the block onthe passenger side, behind the oil filter housing. usually the wires to them are all knackered by this age!

oh and dont worry about the airflow meter, a 16v doesnt have one