Misfire, no power but plenty of misery

**Bullet Fast** · 11-11-2014, 07:50 PM

Soooo... I was just driving along and the car dropped a cylinder at about 5500rpm, like a soft cut limiter. Backed off and it went away. About five km down the road the misfire returned and the car decided it wouldn't drive off idle. Mmm, tow truck!

Anyway, now we have to go problem solving.

The car idles rough, sounds like a boxer. Still free revs fine but with the consistent misfire.

No signs of water in oil. Now undue mechanical noise from the top end. Turbo is still trying to spool under load.

The car showed a misfire on No2 cylinder. But clears fine and only came back once again since. No CEL.

18-20 in hg at idle.

Plugs have been changed. Air filter is clean.

I'm going to start by trying to move the misfire around with coils. A reasonable play this afternoon didn't flick the code again, but I didn't load the engine. Has anyone seen a failed bosch injector before?

A little googling suggests swapping a known good ignition amp in to test. Sydney people?

Any thoughts what the MAF should show at idle? Should it change much whilst free revving? I haven't cleaned or mucked with it. Inside of the airbox was spotless and dry. Oiled K&N panel.

It's a play car, so sitting idle isn't killing me. But it is annoying. I'm betting something small and annoying failed somewhere.

**h100vw** · 11-11-2014, 09:57 PM

Originally Posted by Bullet Fast

Soooo... I was just driving along and the car dropped a cylinder at about 5500rpm, like a soft cut limiter. Backed off and it went away. About five km down the road the misfire returned and the car decided it wouldn't drive off idle. Mmm, tow truck!

Anyway, now we have to go problem solving.

The car idles rough, sounds like a boxer. Still free revs fine but with the consistent misfire.

No signs of water in oil. Now undue mechanical noise from the top end. Turbo is still trying to spool under load.

The car showed a misfire on No2 cylinder. But clears fine and only came back once again since. No CEL.

18-20 in hg at idle.

Plugs have been changed. Air filter is clean.

I'm going to start by trying to move the misfire around with coils. A reasonable play this afternoon didn't flick the code again, but I didn't load the engine. Has anyone seen a failed bosch injector before?

A little googling suggests swapping a known good ignition amp in to test. Sydney people?

Any thoughts what the MAF should show at idle? Should it change much whilst free revving? I haven't cleaned or mucked with it. Inside of the airbox was spotless and dry. Oiled K&N panel.

It's a play car, so sitting idle isn't killing me. But it is annoying. I'm betting something small and annoying failed somewhere.

I'd probably try a set of coilpacks Pete. There was a recall for them, be worth a call to VW to see if you car was part of the campaign and also if it was done, have your VIN ready.

Did you get that other injector in?

Gavin

**Bullet Fast** · 12-11-2014, 05:22 AM

Gav, yes I have and there was no change. I'll try vw today.

**Bullet Fast** · 12-11-2014, 05:17 PM

Originally Posted by h100vw

I'd probably try a set of coilpacks Pete. There was a recall for them, be worth a call to VW to see if you car was part of the campaign and also if it was done, have your VIN ready.

Did you get that other injector in?

Gavin

Gav, I can move the misfire cylinder code with the coil pack. Looks like we have a culprit.

Bonus, VW haven't done the recall on my Polo. Bad news, car won't drive to VW. Any one got a cheap second hand coil pack laying about?

**Eddy** · 12-11-2014, 05:52 PM

Hoyhoy.

I just done a coil pack myself, VW originals are now cheaper than anyone, about $75.00 each.
I didn't muck about, just got the whole set when I was @ Waky last month.