Misfire issue!

[spencerw83]

Hi
Could anybody help with information about a misfire & severe jerking problem on my 94 ABY coupe? It happens when you get past around 3k rpm when the tutbo starts to kick in, it misfires an the car jerks forwards and backwards. It idles and drives fine at low revs. It’s also an intermittent problem, it’s fine some days and plays up on others. It’s recently had a new crank position sensor and I’ve converted it to 2.0tfsi coils using one of Alex (error404) wiring harness’s, but that hasn’t cured it.
Any help would be much appreciated!
Thanks
Spencer

[Error404]

Have you pulled the fault codes? Sounds like a boost leak. Do a full pressure test first

[spencerw83]

How do i go about doing a pressure test? Thanks

[AquaS2]

Are the coils new?

[spencerw83]

Yeah just fitted brand new bosch coils and ngk iridium plugs.

[Antsa]

How do i go about doing a pressure test? Thanks

Here's a guide how to do a boost leak test: https://www.s2forum.com/forum/techni...-testing-draft

[spencerw83]

Thanks mate, appreciate the help!

[bazburn]

MAF...have exactly same on mine, unplug and replug a couple of times sorts it...HTH

[spencerw83]

Really? Well i hope it’s as simple as that! Did that fix it for good or just a while? Is it a problem with the connection or the maf itself?
Thanks mate

[s2driveruk]

Plenty of info under the search button for resolving boost leaks. Check your hoses and jubilee clips and do a pressure check. If the car is new to you then makes a lot of sense to start checking the mile of vacuum lines and intake hoses for cracks and cuts.

[newsh]

MAF...have exactly same on mine, unplug and replug a couple of times sorts it...HTH

This ^^^

My 3B used to do this all the time, finally fixed by properly cleaning the female pins in the free plug by removing them from the housing and running very fine abrasive paper between the contact surfaces. Then a final clean with De-Oxit contact spray.

[newsh]

Read this thread, do a leak test too.

That bloomin MAF connector!

https://r.tapatalk.com/shareLink?share_fid=7870&share_tid=25221&url=https%3A%2F%2Fwww%2Es2forum%2Ecom%2Fmobiquo%2Fredirect%2Ephp%3Ftid%3D25221&share_type=t

[spencerw83]

Thanks guys!

[spencerw83]

Well I’ve cleaned up the MAF connectors and it’s been fine the last few days. Hopefully that’s fixed it but it was intermittent before, so only time will tell.
Thanks for all the help and info guys! Much appreciated!

[bluequattro]

Fuel pump.
I had same issue with an aby
did all things mentioned above with no change.
turned out previous owner fitted Chinese copy that couldn't deliver the goods
put a second hand v6 one in as I had it and ran fine