For god knows what reason, I bought my wife a 98 2.8QS rather than for me. I do drive it once a week or so and I really do drive it.

I've noticed recently when I have really gotten on it, that I feel like the engine is holding back even at 3800 + rpms. All of the sudden it will let go and I'll get more power. It's not like I'm going to stall or anything but I definitely have more power at different times during heavy accel. Does this sound normal or should I be concerned or do I need to run some injector cleaner through the tank?

Advise please.

I usually don't press my A4 very hard, but on a few occasions it feels like the engine is hesitating just a little in the 4-5rpm range. The feeling is very subtle, and I sometimes think it's my imagination. But, perhaps not. Would be grateful for any comments, suggestions.

Thanks in advance.

The 2.8 30V engine has a real nasty flat spot in the 3500-4500 range. The Wetterauer chip has adequately countered this dip in the engine's power curve.

Jeff J 1999 2.8 QMS Wett

they both did that as well. Must be something in the programming of the ECU.

I've noticed that jamming the accelerator to the floor doesn't seem to be the optimal way to go about things. My guess is that there are a couple of reasons for why this is. First, if I'm not mistaken, the ECU will attempt to cut power to the climate control under full throttle. This will cause some funny business at first. Why there's a noticeable sluggishness between 3500 and 4700 RPMs is beyond me, but both cars exhibited it. The valve timing changes at about 4700 RPMs which accounts for the sudden surge of power right there.

I've heard that the chips for the 2.8 will help with that flat spot in the middle. Is it worth multi-hundreds of dollars? Not to me. I'll just ease the throttle to the floor instead of jamming it. Seems to work well enough.

Keith

The ECU controls a vacuum valve that opens the short runners at 4000 rpm regardless of load. This causes more air to enter the cylinders as the short runners are also larger. And this is why you feel the 2.8 having more power at 4000 rpm or so, because it does. The long runners are smaller and provide a smooth idle and smooth get up and go. At high rpm, all the engine cares for is more air fast.