Surging at 1500-2500 rpms?

[KenC]

When I drive my car (M10) in first or second gear I experience some sort of surging of the engine (similar to the surge when you're running out of gas). It happens between 1500-2500 rpms, just when I'm driving slow through a parking lot or something. What could be causing this?

Less than 5k miles ago:
Valves adjusted
Fuel Injectors cleaned
Fuel Filter replaced

Car idles steadily at 850 rpms.

[EtaSport]

Yea, my car started doing that a bit. Feels like the clutch has a flat spot, or its like a super grippy race clutch holding 500 hp, but the old eta is no beast. How old is your O2 sensor? I usually dont plug mine in, but ive been having idle problems with the cold and it helps keep the rpm low. So mine is like completely trashed, i cant believe it would survive my fuel problem. It surges in usually the first three gears when im pulling out under normal acceleration. It also lugs along in parking lots in 2nd gear if im off the gas. The O2 for the m10 cant be more than 70 bucks, check it out, test it.. see what happens.

[Mystikal]

Screw that. Just launch hard enough to keep the revs above such pansy figures and you're good to go. :twisted:

[boom-monkey]

Could possibly be timing. My M10 wasn't timed right when I first got it and it did the same thing.

[KenC]

Yea, my car started doing that a bit. Feels like the clutch has a flat spot, or its like a super grippy race clutch holding 500 hp, but the old eta is no beast. How old is your O2 sensor? I usually dont plug mine in, but ive been having idle problems with the cold and it helps keep the rpm low. So mine is like completely trashed, i cant believe it would survive my fuel problem. It surges in usually the first three gears when im pulling out under normal acceleration. It also lugs along in parking lots in 2nd gear if im off the gas. The O2 for the m10 cant be more than 70 bucks, check it out, test it.. see what happens.

O2 sensor was replaced with the cat and downpipes about 5-10k miles ago.
So I think that can be scratched off of the list.

The O2 for my M10 is only $45 by the way 8)

[KenC]

Could possibly be timing. My M10 wasn't timed right when I first got it and it did the same thing.

Wouldn't that lead to other problems?
The car idles great.
It just had a tune-up at the mechanic less than 5k miles ago.

[BavarianBimmer]

mine does it too but above 4.5k in 3th and 4th gear
i went to my Bimmer dealer 'cause i can't fix the problem
they gave me a bill of $390 and the problem wasn't fixed, adjusted the valves,
new air and fuel filter, advance adjusted,new sparkpugs and wiring, new coil (320i)
cleaned the fuel tank and hoses and a other used fuel pump :roll: