help! Bad hesitation no power, (i read the 78page thread)

[325iklu]

Hey guys i need your help, the 78 page offical thread helped in the begining but now im stumped

I have a 92 325i and it has a bad hesitation between 1k and 3k rpm. It idles rough at about 500rpm. and as NO POWER through the whole rpm range. I had it at WOT just to try to merge on the hwy this morning.

I replaced plugs, fuel filter, swaped in another set of coils, cleaned MAF, then replaced with another MAF and no dice.

Now whats next, bad injectors?

I am picking a multi-meter ftom a friend tonight and gonna test the coils and boots. How do i go about doing this? What ohm range?

:help
-Thanks

[skiboard06]

Did you swap new coils and boots in or just used ones? The resistance should be consistent across the coils, I forget the exact values, there was a thread recently with a guy who posted what it should be. I am confident that this is a coilpack/boot issue for you. Order a new set from BavAuto.com that come with boots and be happy again.

[Flup]

02 sensors maybe? Also check for vacuum leaks (I use either carb cleaner or a small stream of propane and see if the idle bogs down or goes up)

[k3nny]

Sounds like an O2 sensor... from 1-3k RPM and not WOT, you're in closed loop operation, meaning the fuel injection is being based off of your fuel map + oxygen readings. As soon as you put your foot to the floor, you're in open loop operation and not using the oxygen sensor.

How does the car drive when you floor it?

[325iklu]

No i got NO power through the whole RPM range, even at WOT.

I swaped in a set of used coils i had sitting in the basement. No vacuum leaks, checked for that.

I called a local shop and he said that the resistance is .45 ohm + or - 10% for the coils. does this sound right. He also mentioned a weak fuel pump, FPR, or the ground strap on the right side motor mount.

[bobweav]

Check the fuel pressure

[thundercat]

did u warm up the car properly?
because ive had that problem before
Try driving below 3k and easy throttle for like 10 min to warm up the car/.
I do that all the time, and the car is very responsive

[325iklu]

I warmed it up but itended up being 3 of the coil boots had no resistance at all. So i was running on 3 of the 6 cylinders.

CHECK YOUR COIL BOOTS!

[thundercat]

how do i do that?
does this happen all the time, or when cold?
is is a PITA to change?

[325iklu]

get a milti-meter, pull of the boot from the coil and check the resistance from one end to the other.

[fun2drive]

Be aware that checking the ohm range of the coil is WORTHLESS. All you are checking is the primary coil and the coil that breaks down is the 2ndary coil.
The only way to truely test the coil is to remove and replace it with a known good one.
Heed the advice of Mike Miller on BMW Roundel Tech Talk. I screwed around an entire summer and did 3 tests of my coils all checked good. I came to the conclusion that the advice was bad on doing a water spray test and ohm reading test just as I read the November Roundel article by Mike Miller stating the exact same thing...
Glide you got your car running again...

[zarbat007]

http://www.bimmerfest.com/forums/showthread.php?t=188365