I hate this car!!! - BMW Forum

Lower_Level · 10-03-2008, 07:47 PM

sorry for the ranting in advance *mumble*

Well, another day; another attempt to fix failed.

Computer can now be ruled out as the reason for my 325's rpm issues. Still the same; car will not hold between 1200-1800 rpm. It holds for about 3 seconds, then rpm drops to 1200 for a second (almost as if you turned off the car) then jumps back up & repeats. At 2000 rpm's there is a noticeable miss; but no drop in rpm and anything above & below seems fine. Car accelerates strong and doesn't show any driveability issues.

plugs, coils changed, cams checked for timing, all seals on intake replaced, repeated checks for vacuum leaks, sensors checked for resistance & voltage, now computer swapped out

Now what is the most baffling to me is why in the blue hell won't the car tell me what's wrong??? Surely to god the car can't think that everything is fine, and obviously there is something horribly wrong; a sensor or something that is failing; or something is installed incorrectly from when I put the head on months ago. (the problem's been there since day one BTW)

But scans of the car don't show any codes!!!!

WHY! WHY! WHY!!!!

I'm going to do a compression test on the car tomorrow & see if maybe I pooched the head gasket on installation. I haven't seen any signs of coolant in the oil; but there is some condensation coming through the tailpipes. Just looks like carbony water; not oily residue. No overheating issues thus far & doesn't seem to be losing any coolant.

Would the head gasket even cause this type of a problem? or will this be another wasted weekend

spazout1 · 10-03-2008, 11:20 PM

check if itz pulling air simply take sum crab cleaner nd check nd spary araound the intake manifold nd if it corrects itz pulling air

witeshark · 10-03-2008, 11:32 PM

Never give up! I know the feeling!

marti5 · 10-04-2008, 05:13 AM

Well I would say faulty PCV valve.

Lower_Level · 10-04-2008, 07:27 AM

where is the PVC valve on these cars?

marti5 · 10-04-2008, 08:11 AM

It's located under the intake manifold, to the left of the throttle body. It's not really visible without moving the engine harness and the throttle boby, there are four hoses connected to it, one from the valve cover (front of engine valve cover), one from the dip stick, a small 1/4" vacumm hose and another that goes to the intake manifold. The vapors from the engine (via valve cover and dip stick) are routed back into the engine to be burnt again (via the intake manifold), the diaphram in this separator does brake and creates a vacumm leak, in some cases the excessive passing of oil will soften the hoses.

Lower_Level · 10-04-2008, 11:18 AM

will look for that... I don't remember seeing any hoses attached to my oil dipstick tube... maybe that's where the problem is?

marti5 · 10-04-2008, 11:23 AM

Some models differ slightly, but im sure you will work it out, any probs get back to me.

olds72 · 10-04-2008, 12:48 PM

I would look at cleaning the idle control valve (ICV) I have not searched this forum for it but another forum i subscribe to has something on it.
DIY: Cleaning/Replacing Idle Control Valve (ICV)- - Page 3 - Bimmerforums - The Ultimate BMW Forum

Lower_Level · 10-04-2008, 02:06 PM

I looked all over the place & didn't find any loose hoses, or places where there should have been a hose on the dipstick tube.

ICV has been removed & cleaned... twice. Didn't make any differences.

Also did a cold compression test today: 220,210,215,210,210,205 so I guess there's no big problems there.

Will do a test at operating temp maybe later when it stops raining; but I don't think that's where the problem is...