ABY ECU Intermittent issue

[twoqu]

Well basically you would lose the original coil cover although again there are alternatives available which are largely cosmetic. If weatherproofing is an issue then its more problematic as the alternative coils don't seem to like being cooked under the OE cover.
We don't have extensive diagnostics. There are things that fail without codes.
Ultimately if the car performs adequately on stock chips then the issues are either related to the increased stresses whether that be boost or ignition issues or indeed the suitability of the SW which we never really got to the bottom of!

[UrS4boy]

...Or is it just too much for the ignition coils? I can't see anything obvious but have got a spark tester I was going to have a play with.

Re the coils I had started looking at that option, what I couldn't work out was how to use the 2.0 tfsi coils in the existing head without remanufacturing the head cover. Loom wiring isn't an issue and it'll be nice to lose the POS's, but before I start travelling down that road I want to be clear what I'm letting myself in for.

The trick with the coil tester is to use it to find the weak coil, the one with the weakest spark and target it for replacement.

One Missing and Hesitation Diagnostic:

http://forums.quattroworld.com/s4s6/msgs/22611.phtml

As Robin suggested, running the 1.8T or 2.0 TFSI coils under the OE "20V Turbo" coil pack cover for very long will kill them dead, due to heat, sooner than later. You could get away with it for "show and tell"(oops, I meant "Show and Shine" ) events but not for the long term.

The alternative is to run a 7A cover and trim the taller 115E red-top coils to fit. This does require some replumbing for the PVC system, if you are still running one.

[edge_devil]

I took the car for a run over to Hemel today to work and back, and I noticed some similar hesitations and misfires even though I was still running the stock ECU chips. This wasn't expected so when I got home I decided to do some checking, just quick, not got changed still in my smart clothes kinda stuff, if you get what I mean.

I took the inlet tube off that runs next to the rocker cover and checked there wasn't excessive oil traces in it, these were minimal so okay there.
Next I removed the coilpacks and the cover and visually inspected the Coils and wires, all looked good there too.
Now the plug boots, again visually these looked fine, although that probably doesn't mean anything.
While this was all off I decided to have a look at the plugs to see if there was any discolouration, or difference between cylinders. I had only changed these 6 months ago so they all went in new.

It was at this point I found something not quite as expected. The plugs when I came to remove them were slightly more than finger tight, and I know I had torqued them up when I installed them. I elected to leave the plugs in and just torque them up. As with all fault finding, small single changes will help find the issue! I took her out for a run and no misfires, full throttle pulls no issue, still on the stock ECU.

Happy with the status I've put her away and when I get a chance in the next few days I'll drop the other chips back in and see if this has helped.

The boost gauge shows just over the 0 when engine is off, drops into the minus when idling and with the stock ECU shows between 0.9-0.95 at WOT. I'll update when I have run with the other chips to see how much boost and how she runs...

Thanks again for input and I'm still in favour of the TFSI coilpacks, cheaper to replace if one does need replacing and looses the POS's as they are on the TFSI coilpacks.

[UrS4boy]

I am happy that you seem to have found your problem but I am also a little bewildered and sad that you missed Item 1 of my "Monthly Reminder" post, last bumped on April 1, 2015 (a month ago)

http://www.s2forum.com/forum/showthread.php?t=63388

1. Are your spark plugs tight?

Hope everything is good now.

[edge_devil]

Sorry missed that one

'bout time I go pro'd a run or two in this baby now. MOT in the Netherlands on Friday morning next week, then I'll try and drop the Coke Can exhaust silencer back in and wait for dry, quiet roads!, or at least until I come along.