Acceleration lags - United Bimmer Community

**DBB** · 05-08-2007, 05:06 PM

my 325e has a pronounced hitch in its acceleration. gears 1-5. still gets up to speed alright...feels like timing, plugs, wires, fuel injection? wires look ok, not experienced finding vacuum leak. what do i do?

**stevo** · 05-08-2007, 05:15 PM

start by getting the car serviced or do the service yourself making sure you use the correct grade and gapped spark plugs, new bmw spec air filter, use a good injector cleaner additive (redex) or similar, get your timing checked make sure your belts are tensioned correctly, maybe get your ignition coils checked if you still got lag.
check out the knowledge base here on ub plenty of information there.
if all else fails take it to a reputable garage or main dealers and get a full diagnostic done .

**DBB** · 05-08-2007, 05:21 PM

thank you for your reply. one other thing, i'm hearing a light knock shifting down or up between gears. sounds like its coming from passenger side rear.

**stevo** · 05-08-2007, 05:38 PM

Quote:

Originally Posted by DBB

thank you for your reply. one other thing, i'm hearing a light knock shifting down or up between gears. sounds like its coming from passenger side rear.

could be a number of things, you need to get under the car and check all mountings and heat shields also rear trailing arm bushes which i suspect it could be

**theSMELSINATOR** · 05-08-2007, 06:16 PM

try getting a chip for it, too. that helps remove any lag in the RPMs. i hear good things about EAT chips, but you'll have to see if they make one for your car.

**Numark318i** · 05-08-2007, 06:26 PM

I am experiencing the rear thumping noise also. It is a bushing more then likely. might be a subframe bushing.

tell if you find out.

also, check your hoses again, they may look fine, but twist them a little to check if they only look fine. I know my vacuum hoses looked fine, but under closer inspection they were holy. (not the religious type.)

**1985 325E** · 05-09-2007, 11:36 PM

Quote:

Originally Posted by stevo

start by getting the car serviced or do the service yourself making sure you use the correct grade and gapped spark plugs, new bmw spec air filter, use a good injector cleaner additive (redex) or similar, get your timing checked make sure your belts are tensioned correctly, maybe get your ignition coils checked if you still got lag.
check out the knowledge base here on ub plenty of information there.
if all else fails take it to a reputable garage or main dealers and get a full diagnostic done .

Is there a specific area in this forum that has a "library" of this knowledge base you refer to? I have several electrical issues, and have been searching and searching, but have not been able to find anything. I would LOVE to try and find a complete wiring diagram for my 325E.

witeshark · 05-09-2007, 11:43 PM

Try here and http://www.realoem.com

**celsdogg** · 05-10-2007, 08:32 AM

http://www.unitedbimmer.com/forums/129019-post2.html

try downloading that haynes manual. it has electrical/wiring diagrams.

**elsabor67** · 05-10-2007, 11:22 PM

Quote:

Originally Posted by DBB

one other thing, i'm hearing a light knock shifting down or up between gears. sounds like its coming from passenger side rear.

Check your rear bushings. That happened to me on my last E30. and it was NOT fun to change. If you can put it on a lift and push up on it with little effort, get ready to do some wrenching. Good luck.