Geo

after a month in the shop, i have a brand-new outta the crate motor.
my questions: given my modifications (intake, exhaust, stage II chip among others) do i have any recourse with either audi or bosch? at time of the incident i was at 66,200 miles, well over the 50k warranty limit.
(quick recap: with witness/GF in car, at steady 45mph, check engine light comes on and rough running commences. immediate stop.)
i have the spark plug, and the pieces of it from inside the motor.
am i SOL?

Bollinger

Past mileage limit, with all those mods, you won't get any help from Audi.

I'm not saying the mods were at fault, perhaps they were, perhaps not. But either way, Audi isn't going to help you.

I'm sure the check engine light came on when the spark plug broke. That cylinder then was misfiring and caused the check engine light to come on. The ECU may have even noticed the lack of any spark in the cylinder.

Note that a girlfriend isn't considered a great witness when you both are siding against a large company.

Again, I'm not blaming you for anything here, just know that Audi has no obligation to help you.

Rob Pecori

They will likely blame your mods. Under warranty they have to prove that your mods caused the failure. Out of warranty I have heard of Audi covering some turbos but they are very sensitive to mods lately. If you have a good relationship with a dealer I would at least inquire. Good luck.

Rob
98.5 1.8TQMS

eharleq

Recap. What actually happened, since the parts can't flow backwards?

Bollinger

That's what I wonder. If the car lunched one sparkplug, who says it didn't lunch multiple ones over time. If your engine was knocking excessively, it should have fractured multiple sparkplugs over time and thus scored multiple cylinders that way. The ECU should have caught knocking, but of course your engine shouldn't have broken either.

Did you reinstall the same mods onto your new engine? Do you feel doing the same thing again will produce different results?

Geo

#3 plug apparently disintegrated, losing the electrode and part of the porcelain into #3 cylinder. those little bits then 'migrated' to the two adjacent cylinders, leaving lots of scoring and pitting. (i've got the pieces in a bag.)
mea culpa, i had thought plugs were replaced at final 50k service, but turns out it's a 30k service, so after warranty, i 'should' have replaced them again at 60k and i didn't.
cursory check of archives shows two other instances like this, one at 50,100 miles and one in a TT with 239 miles, attributed to spark plugs. i've actually heard from two other mechanics of problems with bosch plugs doing this.
i never noticed any pinging, so apparently the ecu was catching it and retarding timing, but cumulative effect of initial pre-detonation must have done this.
i've replaced the TAP chip with MTM.
on the bright side, it's a brand-new engine with improvements not on my OE engine. and i spent the weekend detailing my car so it's ALL like brand new again. only way to look at it.
(as an aside, i've got to say what a welcome difference the serious discussion is here compared to the A4 chatroom bunch.)

Bollinger

Don't take this as insulting, but of the Bosch's have been known to do this at times, perhaps they are too long? Did you check them?

I'm not an expert on this, but if the new engine is stronger and you do switch away from a TAP chip (which have a rep for pinging), then you probably do stand a good chance of keeping this engine for a while.

DK

Fortunately, the self-adjusting nature of the Bosch ECU does provide for some protection, but up to a point.

What might be a good chip program made on the test vehicle of a particular tuner may not be good for your own vehicle. Too many variables such as manufacturing variances, fuel quality, altitude, general upkeep, spark plug condition, etc may lead to pre-detonation in your particlular vehicle. The ideal situation would be to tune a chip specific to your car, but we don't always live near a tuner.

VW-tool has been invaluable in monitoring my car.

DK

eharleq

The poster mentioned ceramic in seceral cyl. but stated that only one was broken. Seeing as that is unlikely at best, I asked several questions to find out what else may have happened and got no response.

1. The insulators can break due to severe detonation.
2. Severe detonation can happen easily and NOT BE HEARD. I tested this with another brand of chips.
3. Insulator pieces cannot migrate upstream into the induction system, over the manifold and back into other cyls. Nor, can they reversion flow out the valves and back into the adjacent exhaust valves.
4. Shattered insulators may or may not cause significant damage to the cyl. but will certainly knick the turbo blades.
5. A single code simply could explain (as you point out) the loss of the plug.
6. Several mechanics (from my experience) would use the loss of the plug to scam the customer and then resell the old engine.

Geo

i have what's left of the plug, and it's standard.
as for TAP, i got their stage I a long time ago when they were one of the few sources. then upgraded to stage II at their 50% upgrade deal. (does 'penny wise, pound foolish' come to mind?)

with MTM chip and the lesson to change plugs more often, i think the new motor will be ok w/mods.