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Autotechnica
07-11-2003, 02:58 PM
I just got my alternator replaced because my voltage regulator was malfunctioning on my old one. I thought that was the cause of my rough idle and "Check Engine" light. But after the alternator was replaced, I still have the same problems. When I turn on the fan or A/C the idle gets even more rough, at times feels like it's going to stall.

A few things I thought about, possibly the O2 or Oxygen sensor? I've seen some people post about clogged PVC casuing rough idle as well.

Anyways, totally new problem recently and it seems to be getting worse. The check engine light is still on and I noticed that somtimes when I accelerate say from 2500rpm (just an example) the car will bog and then start to accelerate. Almost like turbo lag. Sometimes when I shift from 1st to 2nd I get this bog as well. The car will bog, then start to accelerate again. I don't think it's a misfire, I just changed all the spark plugs and ignition wires. I use Octane 92 fuel. I've also done the clutch slip test and it isn't my clutch. I don't want to change things if it isn't necessary. Just in the past month I've spent over $400 on repairs and I'm really starting to get fed up with it.

I've said it a million times and I'll say it again. BMW's are real money pits.

Any help would be appreciate, thanks!

Just to update, I've owned my '94 318 for 1 year. Here is what I've had replaced/repaired...

engine mounts
shocks/struts/springs
exhaust
A/C freon refill
thermostat
L/R control arm bushings
L/R ball joints
tranny seals
wipers and blades
brakes (rear)
shock mounts
shifter linkage
battery
alternator
ignition wires
spark plugs
X-brace (entire reinfocement bar was missing)
exhaust heat shield (was missing)
power window arms

Lots more I can't recall right now, but god, what a lemon. I enjoy driving the car, it handles great and I can't think of any other car I'd rather own. But the repairs are driving me nuts.

Bry

Gamite
07-11-2003, 03:06 PM
02 sensor? Distribu cap/rotor?

are you running rich? Does the bogging continue after you've driven the car for a while?

djcontra
07-11-2003, 03:09 PM
I know it sounds silly, but check to make sure all the fan blades are still attached to the engine fan. When enough brake off, it creates a really rough idle and problems.

Autotechnica
07-11-2003, 03:13 PM
Originally posted by Gamite
02 sensor? Distribu cap/rotor?

are you running rich? Does the bogging continue after you've driven the car for a while?

It's not running rich, but I haven't really driven the car enough to know when it kicks in exactly. I mean when it does happen the car was driven for no more than 10 min. So I'm sure the normal running engine temp. was not reached, yet it was enough for me to notice there was a problem. The check engine light is on, so there is definitely something wrong.

I can't recall if I've experienced this bogging problem after the car has been driven for a while. However, the rough idle continues reguardless.

Thanks,

Bry

Autotechnica
07-11-2003, 03:15 PM
Originally posted by djcontra
I know it sounds silly, but check to make sure all the fan blades are still attached to the engine fan. When enough brake off, it creates a really rough idle and problems.

Hmmm, that's actually a good idea. I noticed that the previous owner of the car must got been in a minor accident, because the side of the fan cover was ripped up. The fan must have hit the cover when the side was hit. However, when the car is started, the fan seems to spin without hesistation and very smooth. Since Charlie had removed my fan previously I doubt the blades are missing but I will check. Thanks for the advice though, everything helps. :)

Bry

djcontra
07-11-2003, 03:32 PM
Also, one thing I usually suggest first is trying to reset the computer by disconnecting the battery for 15mins. It did wonders for my car the other day when I reset the computer. Now the drive is much smoother and I get better gas consumption.

sadda///M
07-11-2003, 03:32 PM
ummmm could be a number of things:

vacuum leak
fuel injector
fuel pump
fuel pump relay
fuel pump regulator
air mass sensor
clogged fuel filter
clogged air filter
dist cap/rotor (if yours em)
comp

KIRASIR
07-11-2003, 05:04 PM
I agree with sadda///M. Start by changing the fuel filter first.

SL


Originally posted by sadda///M
ummmm could be a number of things:

vacuum leak
fuel injector
fuel pump
fuel pump relay
fuel pump regulator
air mass sensor
clogged fuel filter
clogged air filter
dist cap/rotor (if yours em)
comp

Autotechnica
07-11-2003, 05:39 PM
It's not a vaccum leak for sure. I changed all my hoses in advance after I purchased my car. The MAF is also not malfunctioning, I had this checked out. The air filter is a new K&N CAI. I haven't changed the fuel filter before and I have no idea how.

Where is the fuel filter located and how much does it costs? Can I change this myself?

I used 2 bottles of fuel injector cleaner (concentrated) but how can I check to see if an injector is physically clogged? Will it be easy to remove?

My mechanic suggested that I change the O2 sensor, does this sound like an O2 sensor problem?

I realize that it's difficult to diagnose the problem. But I just wanted some opinions before I try the replace everything till it works method.

Thanks!

Bryan

djcontra
07-11-2003, 05:51 PM
A fuel filter is only about $15 or less. I had it changed on my last car and it made the car run a lot smoother. Only downside is I used more fuel afterwards :)

I'm not sure where it'd be on your engine though :(

Autotechnica
07-11-2003, 05:52 PM
Originally posted by djcontra
A fuel filter is only about $15 or less. I had it changed on my last car and it made the car run a lot smoother. Only downside is I used more fuel afterwards :)

I'm not sure where it'd be on your engine though :(

Thanks! Did you change it yourself? If so, was it difficult?

Bry

moregothanshow
07-11-2003, 07:41 PM
i have that same problem too...it kinda lags right when i start driving the car...but after that it is fine/when it warms up....can someone tell me what is wrong with my car?
Thanks!

djcontra
07-11-2003, 07:52 PM
Originally posted by Autotechnica
Thanks! Did you change it yourself? If so, was it difficult?

Bry

No, my mechanic did it for me, and later told me I could have probably done it myself. He didn't charge me any labour for the job since he said it was so easy.

Gamite
07-11-2003, 07:53 PM
Originally posted by djcontra
I know it sounds silly, but check to make sure all the fan blades are still attached to the engine fan. When enough brake off, it creates a really rough idle and problems.

I've had a similar problem, my clutch fan siezed up and all the ball bearings inside were messed up, it was incredible to the amount of vibration it made.



Bryan, check your fan, maybe the clutch is gone too?

Gamite
07-11-2003, 07:54 PM
Originally posted by moregothanshow
i have that same problem too...it kinda lags right when i start driving the car...but after that it is fine/when it warms up....can someone tell me what is wrong with my car?
Thanks!

My car is doing that right now, and I think its running rich.

sadda///M
07-11-2003, 10:05 PM
Originally posted by Gamite
My car is doing that right now, and I think its running rich.


o2 sensor plays a role in air/fuel mixture so if car is running too rich or too lean, most prolly the o2 is the culprit.

and just in case someone would just to adjust the timing, i think the comp manages the timing so it's not adjustable...to newer model cars anyway

KIRASIR
07-11-2003, 10:36 PM
The fuel filter is 40 bucks and is located under the drivers seat, under the car. Takes about 10 min to change.

m42/m44 have electric fans(not engine driven) so it's not a fan clutch and not a broken blade.

SL

moregothanshow
07-12-2003, 01:30 AM
i think i should change my fuel filter....any more in-depth instructions on how to do this? i think it hasnt been changed since 95....
Thanks!

Autotechnica
07-12-2003, 01:37 AM
Originally posted by KIRASIR
The fuel filter is 40 bucks and is located under the drivers seat, under the car. Takes about 10 min to change.

m42/m44 have electric fans(not engine driven) so it's not a fan clutch and not a broken blade.

SL

Wow, so the fan isn't robbing any precious HP from the engine? I never knew M42/M44 had electric fans. So I guess my idea of an electric fan conversion was totally retarded. Are you positive the M42's fan is electric? Thanks! Learn something new everyday!

Where is the best place to get a fuel filter? Dealer or crappy tire?

Bry

KIRASIR
07-12-2003, 02:28 AM
Look inside your engine and tell me if the fan is connected to the engine in any way? Is there a belt going to it? I doubt it. :)

Get the OEM filter from the dealer. To change do the following:

1) pull the fuel pump fuse
2) run the car dry of fuel
3) jack up the drivers side
4) take off the filter cover
5) undo the 2 hose clamps from the fuel filter, and the bracket.
6) take out the filter
7) put the new one in, make sure the direction is correct,
8)put the clamps/hoses back on
9)bolt it up and reattache the cover
10) put the fuse in, and start the car, make sure that no fuel is leaking from the hoses
11) done.

SL


Originally posted by Autotechnica
Wow, so the fan isn't robbing any precious HP from the engine? I never knew M42/M44 had electric fans. So I guess my idea of an electric fan conversion was totally retarded. Are you positive the M42's fan is electric? Thanks! Learn something new everyday!

Where is the best place to get a fuel filter? Dealer or crappy tire?

Bry

moregothanshow
07-12-2003, 07:05 PM
ok wehn u say run the fuel dry, do u mean to drive til there is no fuel in my car??!?
Thanks!

KIRASIR
07-12-2003, 07:43 PM
Yes. Take the fuel pump fuse out. Start the car, and wait till the car dies.

SL

Originally posted by moregothanshow
ok wehn u say run the fuel dry, do u mean to drive til there is no fuel in my car??!?
Thanks!

moregothanshow
07-12-2003, 08:42 PM
oh ok....i thought u meant to drive the car around the block til there was no fuel in the tank or car at all... i was like say the car dies at the end of the block?!?!:confused:
Thanks!

Autotechnica
07-12-2003, 10:07 PM
Originally posted by KIRASIR
Yes. Take the fuel pump fuse out. Start the car, and wait till the car dies.

SL

Isn't that bad for the car? Anyways, seems like more than a 10 min job. Probably going to take me an hour +.

Thanks,

Bry

Gamite
07-12-2003, 10:49 PM
isnt that bad for the car? wouldnt it be better just to use 2 vice grips to clamp the hoses?

moregothanshow
07-12-2003, 10:51 PM
thats what i thought.....hey autotech u want to find some time and do this?!? i am afraid i am pretty newb....but would like to try...

KIRASIR
07-13-2003, 02:57 AM
Clamping the hoses can be a bit tricky since the fuel lines are metal with 5cm rubber pieces on both sides of the filter. It might work but getting the filter out will be a total pain in the ass since there is very little space in there.

BTW make sure you have a container to catch the fuel that will come out of the fuel filter.

SL

Originally posted by Gamite
isnt that bad for the car? wouldnt it be better just to use 2 vice grips to clamp the hoses?

Adriano
07-19-2003, 03:34 PM
PLEASE PLEASE do me a favour! Get your engine code read!!! That will give us more info as to what the problem is. If your O2 is NFG, then the code will be stored on the computer. Don't waste your time doing anything else untill you get your codes read!!!

nzer
07-20-2003, 02:27 AM
Originally posted by KIRASIR
Look inside your engine and tell me if the fan is connected to the engine in any way? Is there a belt going to it? I doubt it. :)


there probably wouldn't be a belt going to it.. it would be connected to the water pump and be a viscosity clutched fan, a belt to the water pump perhaps.

Autotechnica
07-20-2003, 04:06 AM
Fan is belt driven. Driven by the engine and runs the alternator and the fan.

Adriano,

I forget how to do this. I have Motronic 1.x. I tried turning the key to the on position but not starting the car. Pressing the gas pedal and releasing it 5 times. This is what I did on my previous '92 and it worked. Only this time on my '94 it doesn't work. Am I doing something wrong?

Thanks,

Bry

Jon@Bimmersport
07-20-2003, 03:50 PM
my bros car does this as well at idle...it shakes like it has a 5.0L mustang motor in it..wtf is up with that?

Autotechnica
07-20-2003, 05:52 PM
Originally posted by E46_lover
my bros car does this as well at idle...it shakes like it has a 5.0L mustang motor in it..wtf is up with that?

Maybe the Engine/Tranny mounts are worn?

My engine is only rough when the idle is irradic. When the idle is constant the engine is very smooth and quiet.

Bry

Adriano
07-20-2003, 11:53 PM
I forget how to do it for your car because I have a friend with a OTC computer. You can buy the basic BMW code readers from ebay for a good price. This will definately tell you what the problem is.

Autotechnica
07-22-2003, 07:12 PM
Got the fuel filter today at BMW T&C for $40 w/ BMWCC discount. I saved like $8! BMW membership pays for itself in the long run.

Anyways, to anyone who is familiar with the fuel filters, I got the short version. It seems to have a plastic cap inside the filter which I can see through the hole. It has the number 5 on it. Should that be in there? Doesn't look like I can remove it.

Thanks,

Bry

djcontra
09-13-2003, 11:31 AM
bryan, did you ever get this fixed ? I'm having the same trouble right now, and I'm almost positive it's my o2 sensor.
The shitty thing is, is that I just replaced it only 4 months ago, and it's already fried :(

My symptoms are, the car will run at 750rpm when started, but then if I step on the gas, when the rpms drop back down, they drop almost to the stalling point, and then it levels itself out after a few computer driven revs. It does this whether the car is hot or cold. I know it's not my PCV, EGR, Carbon Canister, or any of that stuff because I dont have any of those things on my car anymore! :D

R_JAY
09-13-2003, 04:56 PM
Contra, I've been having the same problem since the end of last winter. I was told that my idle control valve is sticking so you could try looking at that.

Autotechnica
09-13-2003, 07:50 PM
Hey guys,

I got it fixed. Turned out to be my "Purge Valve" which was what the fault codes read anways. One of the wires were corroded and broke off. So once it was reconneted the problem was fixed.

Bry

djcontra
09-13-2003, 08:00 PM
hmm i'm going to check that next myself.
I think I've fixed my problem though, or at least figured out what it was. My idle control valve was REALLY gummed up, so I removed it, cleaned it with throttle body cleaner, and put it back in. It made a HUGE difference for me; my car runs like it's brand new now! The unit was such a pain in the ass to remove though, and I hurt my arms pretty bad in the process.
My next task is to clean the spark plugs from all the carbon deposit that's caked on from all these idle troubles.

djcontra
09-15-2003, 03:22 AM
I finally figured it out! My intake boot (the rubber piece that connects to the throttle body) blew a hole out the bottom from all the supercharger pressure! lol!
no wonder my car was going so slow lately heheheh
I remember hearing a huge "POP!" sound when I was racing a mustang on kingston road, but I figured it was something inside my engine (something serious). I guess I'll just have to replace it with a metal one soon enough...luckily I had spares lying around, so all is well now, and TiTAN is back in action! *th-up*

Autotechnica
09-15-2003, 04:04 AM
Originally posted by djcontra
I finally figured it out! My intake boot (the rubber piece that connects to the throttle body) blew a hole out the bottom from all the supercharger pressure! lol!
no wonder my car was going so slow lately heheheh
I remember hearing a huge "POP!" sound when I was racing a mustang on kingston road, but I figured it was something inside my engine (something serious). I guess I'll just have to replace it with a metal one soon enough...luckily I had spares lying around, so all is well now, and TiTAN is back in action! *th-up*

Yeah that's a very common problem. It's happened to me twice already. It's always the first thing I check when there is rough idle or loss of power.

Bry

DriveItSideways
09-16-2003, 09:49 PM
i just started getting the same problem minus the check engine light, when i first start the car, the rpms jump up to 2500 and then almost all the way down until the car starts to stutter then it starts to idle somewhat smoothely, and also when im at a stop and i accelerate very slowly the car boggs down, i checked all my hoses and it looks good, my throttle body was kinda dirty so i cleaned her up but that didnt help at all, wtf is going on?! its a really annoying problem..

djcontra
09-17-2003, 02:49 AM
probably the idle control valve like I experienced on my car. It just needs to be cleaned out, and relubricated.
it's a b*tch to get out though; I have bruises on my arms from wrenching it under the intake plenlum trying to get ICV out.