Misfire when under load VAGCOM RESULTS PG 2

cupra_spencer

Active Member
Jan 19, 2009
105
0
Hi all.
my car has been misfiring recently even on idle so i changed the offending coilpack for a new one and now it idles fine but goes onto 3 cylinders when you put your foot down?

any ideas? has got new plugs in also...
 
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ian_cupra

Guest
another coilpack, sometimes they miss under load, and sometimes totally
 

cupra_spencer

Active Member
Jan 19, 2009
105
0
thanks for that mate. just kinda tested the coils out by starting the engine and lifting each coil out to see if it was sparking.

looking at the front of the car it was the 2nd in from the left that i thought had gone as i did this test and this was the only one not sparking and once replaced it then idled fine. so i replaced it with a brand new one tonite

then i took it out for a drive and anything over 7psi it runs on 3 cylinders.

so i did the test again. the coil furthest left was sparking intermittently then stopping then starting then stopping etc. and when i put it back on the car the car idled smooth again. did the same with the one i just replaced (£30) and this one didnt have a spark at all? the next two did (the one on the far right and the one next to it)

i dont understand... surely there would be an intermittent regular spark pattern on all? the only one that i would say may be faulty is the one on the far left that sparks then stops then sparks again.

what would you say?
 

ian_cupra

Guest
its just the extra load thats doing it, coil is just giving up
 

cupra_spencer

Active Member
Jan 19, 2009
105
0
so would you advise replacing the other three or just do it one at a time?

strapped for cash thats all mate.
 

ian_cupra

Guest
get one, and try it in each one til you get it right

if you can afford it get them all
 
Jan 8, 2007
2,958
1
Wiltshire
Often once one goes the others soon follow. When a coil goes it can weaken the others with the extra work they have to do to keep the engine running. When my first one went the remaining 3 went within 6 weeks at random intervals
 

cupra_spencer

Active Member
Jan 19, 2009
105
0
get one, and try it in each one til you get it right

if you can afford it get them all

right.

i have changed all the coils for new ones and just bought some new spark plugs also. all fitted and i still got the problem. is a patially blocked injector possible?

if so, im thinkin that it is getting enough fuel into the offending cylinder on low boost but when it comes on high boost the fuelling is increased in all cylinders apart from one of them due to the injector being partially blocked?

please help! iv had the car 1 week and all iv had so far is problems! just want it running right!
:(

any more ideas?
 

cupra_spencer

Active Member
Jan 19, 2009
105
0
My car felt like it was misfiring under load and after checking the coils it turned out to be the MAF.

i have tried unplugging the MAF sensor and running the car but the problem stays the same.

i rang seat and they want £65 + VAT for a diagnostics!!!

they also said it could be a valve sticking??? somehow i dont think so.
 

ian_cupra

Guest
where you based? could try and find someone on here local to you and see if they would be so kind as to vag-com your car
 

ian_cupra

Guest
if you post in the vag-com area of the forum, asking for help in your area, hopefuly someone will be able to help you :D
 
Jun 17, 2007
1,032
0
Aberdeenshire
I hve had same problem as you and went through the elimination process after on vagcom

of maf, n75, precat lambda, and eventually got down to the spark plugs, coil packs and thats the end of it.

Some expense.
 
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