hello im new to this forum but friends tell me its the best! i have a 1991 850i that starts up ruff then idles smooth,soon after driving a few moments it boggs down and i retap tap gas petal and it jumps back to life. it does this all day while im driving. i changed the eml both throttle bodies and changed both O2 sensors is there anything else that could be giving me this problem and are there any ideas what i should do next thanks!!!!!!!!!!!!!

sounds like the fuel filters may need to be changed.

Intake manifold gaskets in good shape?

Check if the O2 sensors are connected correctly, i.e. driver's side sensor hooked up to left bank DME and vice versa. I've had this issue twice. First time on my E34-540i and second time on my 850. In both cases the engine ran like sh** and it drove me nuts until I found the root cause.

Good luck
Wolf

it actually ran better after changing O2 sensors for about 30 min then same ole same ole there after?

also changed both fuel filters?

Wolf's probably right though, Make sure the O2 connections aren't crossed.

Here's my 2 cents:

1. Fuel Filters need to be changed every couple of years
2. O2 sensors crossed
3. Intake Manifold gaskets
4. VCV valve aka Volume Control Valve (PCV for V8)
4. Check for vacuum breach

my car did this, and after changing all sensors it turned out to be a bad fuel pump. check to see if you have good fuel pressure on both fuel lines.

2 baterys.3 wokke chips. gallons of wuffer red. and lots of luck.

2 baterys.3 wokke chips. gallons of wuffer red. and lots of luck.

Give me some of the wuffer red!