Misfires?

ChrisCurzon

4WD FTW
Apr 9, 2006
1,821
0
Bolton
the 20vt doesnt have leads, it has coil packs / pencils or whatever you wanna call them

gas_igncoils3.jpg


I'm sure misfiring can also be caused by a dud MAF, have you logged the MAF? Also things you REALLY dont want to think about...loss of compression which could be leaking cylinder head gasket, leaking or sticking cylinder valves, worn pistons, liners or rings, or a cracked cylinder head or block. but hopefully the MAF :p

thats worrying as still not sorted mine and had new maf coil packs spark plugs and checked for boost leaks :headhurt:
 

ChrisCurzon

4WD FTW
Apr 9, 2006
1,821
0
Bolton
not really sure what it is when your just about to hit full boost it stops reving and make really loud bangs and just holds back the boost gauge will flick between 15-20psi but revs wont increase and logs so no cf's and nothing jumping out as a problem and no fault codes come up at all.
 

thewiizard

Tarmac Tantaliser
Jan 15, 2007
486
0
Rugby, Midlands
www.tbfh.org
not really sure what it is when your just about to hit full boost it stops reving and make really loud bangs and just holds back the boost gauge will flick between 15-20psi but revs wont increase and logs so no cf's and nothing jumping out as a problem and no fault codes come up at all.

Hmmm, What does your rev counter do when all this is going on?

I'm thinking at the moment that it could be a couple of things;

Ignition Timing - Check your belt timings, as you rev harder your timing is automatically advanced, if your timing is slightly out, your ECU maybe winding it too far forwards causing firstly, your lack of power and secondly the backfiring effect your getting when the power loss happens.

Basically, backfires are caused by fuel sitting unburned in the cylinder and being cleared out through the exhaust, if your spark is in the wrong place your effectively making a mortar cannon out of your system when this excess fuel is ignited, sounds cool but doesn't do much good for your emission control.

May not be the issue but worth checking on all accounts..

Fuel Supply and Delivery - Get your injectors pressure and flow tested, make sure your not spitting bubbles instead of spraying mist, might also be worth checking your throttle body is clean and aligned correctly.

That should be enough to keep your mind ticking for a little while.
 
Last edited:

ChrisCurzon

4WD FTW
Apr 9, 2006
1,821
0
Bolton
how no idea on how to do most of that but sure i can get some one to look at it for me cheers.

when it has teh problem kinda of stops reving liek tis hit the redline but it doesent do ti all the time some times will work with just abit of a splutter other times wont go at all.
 
Genuine SEAT Parts and Accessories.