Annoying Misfire

[GTIAndy 0]

Hi I have a very annoying misfire on my 1.6 GTI it occurs mainly if i am holding the car at set revs eg driving in traffic at say 3000 rpm it's nothing major just hesitant, when accelerating it pulls ok, but overall it just doesn't seem smooth. Ticks over fine and steady

 

So far I have

 

New ign leads

rotor arm + cap

new plugs

fuel filter

checked SAD which seems to be working

checked for any air leaks

 

Any other ideas?

[timb1046 1]

is it deffinatly a missfire, not just the car juddering, pointing to TPS?

[The Arch Bishop 0]

I'd say either the coil and/or ignition amp. Mine turned out to be the coil but many others have found it to be the ignition amp.

[GTIAndy 0]

It's definitely missing, sometimes it just seems to come together and run smooth and then other just this subtle missing.

 

Best place to buy an amp and coil anyone?

[The Arch Bishop 0]

You can get non OE replacement coils from any decent motor factors but I have no idea if they're any good. I got a second hand Bosch one from a forum member. Amp's are best sourced from a scrap yard or by putting a wanted ad up on this forum. Don't buy anything other than a Bosch amp though as the non OE ones (Intermotor springs to mind) are big trouble. If you're replacing the amp, make sure you've got some computer heat sink paste to smear on the metal back that buts up to the alu' mounting plate or it'll overheat very quickly.

Edited May 23, 2010 by The Arch Bishop

[GTIAndy 0]

is there any way to test the amp? before I replace

[gixxerash 0]

You can get non OE replacement coils from any decent motor factors but I have no idea if they're any good. I got a second hand Bosch one from a forum member. Amp's are best sourced from a scrap yard or by putting a wanted ad up on this forum. Don't buy anything other than a Bosch amp though as the non OE ones (Intermotor springs to mind) are big trouble. If you're replacing the amp, make sure you've got some computer heat sink paste to smear on the metal back that buts up to the alu' mounting plate or it'll overheat very quickly.

 

 

to Arch bishop is this the stuff you are on about. I forgot to put it on mine do you whack loads on or just a light smear of it.

 

is there any way to test the amp? before I replace

 

if you get stuck p.m me i have one you can borrow..

Edited May 23, 2010 by gixxerash

[The Arch Bishop 0]

A fairly light, even coating will do. Not sure if there's any way to multimeter them but the easiest way is just to plug them in and go for a blast!

[P_Monty 2]

Rats - I didn't realise you needed paste when I did mine. Hope I don't kill it before I borrow some from work...

[GTIAndy 0]

to Arch bishop is this the stuff you are on about. I forgot to put it on mine do you whack loads on or just a light smear of it.

 

is there any way to test the amp? before I replace

 

if you get stuck p.m me i have one you can borrow..

 

 

Thanks for the offer I'll try a new coil first, but then may take you up on the amp

[bazil_205gti 22]

had a misfire on mine and was very hesitant changed the amp and away she went good luck mate.