Hesitating above 6500...

[windsor318is]

i think its a combination of pump and filter, we are forgetting how old these cars are. and its been awhile im sure since people have changed there filters.

[e30s52]

If it's not fuel, it might have something to do with vanos?

its not vanos my m50 non-vanos did the same thing. i just replaced the fuel filter and it stoped.

[scabzzzz]

In my M52 swapped car, my fuel filter was dirty and it did that. I had stock programming as well.

[DCColegrove]

What engine are we talking about?

I've had M52's and TUs float valves at high rev's when the oil was nasty.

Bad coils, plugs etc can do it too under heavy load.

[dark89e30]

Ignition. OE plugs? VCG?

[e30polak]

If it's not fuel, it might have something to do with vanos?

[matt]

Only once in a while?

[BigD]

How old is your fuel pump/filter? Me and windsor318is are having an extreme version of that. He knows it's his pump, I'm 99% sure it is (and/or filter).

[MR 325]

Once is a while when I take the car to redline it will start to hesitate starting anywhere from 6200-6500 and all the way to redline. I'm wondering if anybody has had anything like this go on with their cars and what may cause it.

I'm thinking it's a fuel issue but of course haven't really looked in to it much at this point. It's definitely not a bad ground to the engine or coils. The wierd thing si I have been driving this car since November with the motor and this has only started to happen in the last couple weeks.