I got the Giac 93 octane chip upgrade and now the car runs fine, great, wonderful. Except if I shift early and floor it. In 3rd and 6th if im going to slow and put the gas to the floor like.....80mph then go to 6th gear and floor it or 20mph and get to 3rd and floor it ill get a flashing check engine light. Today I tried to push it through the misfiring by continuing pressing on the gas and the check eng. flashed then registered a code to my ECU, if I didnt stop there would be some serious damage, but after I went back to 5th then up to 6th at 120 no problems all the way to...well, i much higher speed. If im not driving conservativly or flat out gear to gear maxed out redlining it I get misfires on those two gears. Has ANYONE, had these problems? Electrical? Fuel? does it need to be mapped again? anyone thats had similar problems id love to hear from. ive got plenty of ideas, new injectors, new pump, grounding kit, coils, spark plugs. But I would love it if someone has had this problem too. Thanks







2001 Audi S4
ASP 3" DP's
Borla 3" cat-back
Bailey Motorsport Diverters
Samco silicone hoses
RS4 kit
18" ADR M-sport wheels
HP racing full suspension
Giac 93 Oct chip upgrade
UUC short shift
RS4 Grill
Smoked Tail Lights

 

What was the code? Flashing light = BAD.

Might be a failing coil pack, loose plug, bad injector, way to much to just guess.

can you put it in stock mode & redo your test?

 

MIL only flashes to indicate catalyst damage i.e. raw fuel being spewed into the converters. definately an ignition issue. check coil packs. let it idle and get a squirt bottle w/ water and spray each coin individually. if you spray one and it starts arcing and misfirring...booya, thats a bad coil. if not, check other ignition componants.

 

I had this problem last year and it was EGT sensor drivers side. It was throwing P0300 code(Random misfires)
the engine RPM was cutting and the power was bad. You may look out for that ! The sensor itself
sells for 180-200$ range and it's about an hour to change on the drivers side or 25 min on the
passenger side. I don't beleave that Coil Pack are an issue unless they are on the same cylinders
all the time. Try to VAG for codes and you'll know.

 

Chebert you make a good point, the random cylinders and the fact that ALL of the cylinders would misfire doesnt specify any one bad coil, unless they are all bad which is pretty impossible. AND, I am losing a lot of power from driving, sometimes I can pour out the speed, other times I feel like im driving the A4. (nothing personal to any A4 owners) EGT sensor? The code was P0300! Thanks man, ill get on that and let you know if it does the trick by the end of the week.

 

The problem is fixed, but im out of the frying pan into the blazing hot abyss of hell. My car loves me sooooooo much it decided to triple-screw me over. Coming back from somwhere I hit a bump, nothing special, just a bump. I lost my stability control and ABS, which according to the owners manual, go hand and hand. So if the ABS kicks so does Stab Control. I turn the car off then back on to attempt to reset and clear the code (assuming it was a minor joggle from the bump) and WHAM! Check engine light strikes again. Except now its making things tough. When the car is turned on the ECU fuse pops. So I take it to Audi and they replace the fuse, then start the car, again the fuse pops. They cant figure it out but they wanted to pull the ECU and replace it. Now I have Giac and my performance tech racing all over this problem because the car runs......it just has decreased performance and brake light issues. Looks like ill have to get the ECU reloaded. Or just clear the ECU by disconnecting the battery for 10 min and then resetting it with the key in the on position for 5 min. Anyone have any other thoughts?