Detonation?

[Low Impedance]

Little background.

2g TSI awd automatic car. Stock exhaust, hacked intake. ARC bov. 13g @ 18ish psi. stock otherwise. 94 octane

i installed the 13g in feburary. It was obviously cold outside then.

okay so friday night i went to "Get on it" and my car basically felt like it hit a brick wall. And start idling terribly. To the point where i could not really drive it. So, i had it towed back to the marathon station i quasi work at and put it in the bay. Figuring the worst i pulled the spark plug out the of farthest left (#4?) cyclinder. And the ceramic shielding around the electriode has broken and was against the prong covering the electrode. So whatever i figured that it was the crappy autolites. So i replaced it with another autolite. Next morning it did it again. Pulled the pull and again, broken...

hmmm..

so i went and got the NGKs. Went down the street okay with a little shutter for a 1/4 sec at full boost. Then coming back up, same brick wall feeling and the weedwhacker idle. Get back to the station and pulled the plug. Plug was okay but has turn white immediately. So i replaced the fuel injector from a 1g (blue tops) Worked fine. Cool i solved the terrible detonation problem.

Well tonight i did a little launch and it seemed like it missed about three times. that "no power" with a backfire for a 1/4 second. about three times at WOT and full boost with a power brake launch right i after i started off. so i let off and just creeped into fullish boost area at 3/4 throttle. Didnt do it.

So whats the deal!?! It didnt feel like the brick wall but it obviously isnt good.

Is the fact i have no fuel control causing detonation with the 94 octane now that it is warmer outside? Is the turbo starting to sieze a little?

 

[slo95tsi]

have you checked for boost leaks?? i had the same problem and so i made a boost leak tester from vfaq and tested for leaks and wha laa! Fixed the leaks and she was running perfect again!

 

[Low Impedance]

ill give it a try. i assume you do this with the TB open?

 

[romeen]

No you don't need to have the TB plate open when doing a boost leak test. Boost leak tests are a good idea anytime the car is not performing well. But even though you may very well have some leaks it doesn't sound like that is the cause of your problem.

If you are still on the stock fuel system then 18 psi is definitely too high, even with the 94 octane (lucky you!). Turn the boost down to about 15-16 psi. I'm sure you know how damaging detonation can be! That "hitting the brick wall" feeling was likely fuel cut although it could have also been the moment that the spark plug was destroyed.

Until you get these issues straightened out and the car is running well I wouldn't recommend doing any "power brake launches" or going WOT. You could end up with costly damage.

 

[Low Impedance]

yeah i turned it down to the 14ish range this morning. I have a spearco top->bottom laying around i might as well put in. and i guess the next paycheck is going towards a DSMlink.