rough running 318 help

[tmd7089]

Hello all. I am new to this forum and bmw in general. Ive already read through some of the sticky threads to familiarize myself with with this car.

Anyway, I recently got a 1994 318is. The car had been sitting for a long time. It took a little while to get it to start, but eventually it did. Now the car starts right up for the most part, but after running for a few minutes, it starts to misfire and if it sits idling unattended, it will die. I am in the process of doing a tune up on it, I have new plugs for it that I plan on installing. I am just waiting on getting the O-ring spark plug seals that go between the valve cover and the head because currently cyl 1,2, and 3 are bathed in oil. Now I am hoping that this is the cause of my problem.

However, If after I change the plugs and gasket, the rough running persists, does anybody have any other ideas as to how to get the car to run correctly again? Does this sound like it could be 02 sensor or MAF related? Also, I changed the fuel filter and put some fresh gas in it too, so that should be ok. I need to get this issue sorted out quickly because I'll be taking the car away to school with me which is like 6 hours away.

Thanks in advance for any suggestions and I look forward to learning from this forum.

[keeslinger31]

tune up as said. Compression test just for giggles. Oil change since its been sitting. You say the plugs are bathed in oil? The electrode end?

[UnderCoverGuy11]

Spark plug o rings? Why not replace the whole valve cover gasket? That's your problem if you have oil there. Is the car throwing any codes at all? If you think the MAF is the problem just unplug it and if it works normally then replace the MAF. Clean the idle control valve, might solve your unattended idling problem. As for rough running, can you be a little more specific as to what the problem is?

[tmd7089]

Already change the oil. I intended on replacing the entire gasket and I ordered one from advance auto (yea I know) and it arrived but it dosen't include the o rings. My buddy said the orings were part of the gasket on his m3, don't know if this is the case on the m42? I'll try diconnecting the maf for now. The oil was all the plug wire. I didnt actually pull the plug so Idk what the electrode end looks like.

As far as what it does: It just misfires after its been running for a few minutes. At idle it starts missing and the car starts to shake like any other car not running on all cylinders. When you drive down the road it sputters also.

[RsKeyz]

The O-rings are separate and need to be ordered separately, unless the place you purchased your gasket from put them together as a kit. Pelican parts sells entire kits which also include the rubber grommets for all the valve cover bolts., check their website out. Also check out realoem.com. Type in your car and look at the diagrams. You will get a good idea of all the gaskets involved.
Misfiring could be quite a few things, possible vacuum leak, MAF, etc. Start by replacing those gaskets and inspecting your vac hoses for cracks while your hands are dirty and go from there. Badly deteriorated gaskets could effectively act as a vacuum leak and cause rough running.

[tmd7089]

just ordered those o rings thanks for the site recommendation. Hopefully they do the job

[Im Over It]

Check the dizzi cap and rotor, mine have now done 320,000kms and when it was mis-firing i checked em and they were all arked out, put new ones in and now its fine.

[flyfishvt]

94 318 is a M42 engine. It doesn't have a cap and rotor. they discontinued those after the M40.

[wbarfels]

do a search for "stuttering Beemer hell....fixed" or just click on my name and youll see it in my post list, May be of some use to you.

[DeanR]

Plugs, plug wires and coil pack are all areas to check if you have spark issues.
Also clean you MAF and check for vaccum leaks.

[medic1dl]

I don't think anyone mentioned that one possibility could be that the cat is blocked.

[flyfishvt]

This whole discussion is taking place before he cleans the plug wells and replaces the plugs. I'm waiting for this to take place before offering any further advice. I'd bet he will end up with a perfectly running car after doing the plugs.

[318bud]

youd be suprised what an oil change could do....if you havnt already

[tmd7089]

do a search for "stuttering Beemer hell....fixed" or just click on my name and youll see it in my post list, May be of some use to you.

Just read through your thread and its definately helpful. I really wanna do these damn plugs already to see if they are the problem. The o rings are supposed to come tomorrow. I have my fingers crossed as I'd rather not have to lay out the $ for an 02 sensor, wires, coil, etc.

[tmd7089]

-Ok so heres an update. I replaced the plugs along with the valve cover gasket and plug o rings. Same as before if not worse.

-Afterwards, my father and I checked a few things out. With the car running, pulling a wire off of the spark plug made the car run worse on each cylinder.

-After that, we sprayed carb cleaner around the engine bay with the engine running to try and find a vacuum leak. There was in fact a leak which seemed close to the fuel rail. So, I replaced the intake manifold gaskets (upper and lower) and replaced the fuel injector o-rings. Also I replaced whatever crappy vacuum hoses I could get to while I was in there.

-Just tried it and its still the same as before. It seems like the engine has the most trouble when trying to hold a constant rpm. It starts sputtering after holding the same rpm for like 1 secound. When you drive the car up and down the street, you don't really feel anything out of the ordinary. when you stop, you must keep the car running via your foot or it will die.

Any more suggestions? I'm running out of ideas and time at this point.

[slocar]

Sounds to me like the idle control valve is clogged/dirty and not responding quickly enough to maintain idle and it dies due to lack of air ... when you keep your foot on the throttle, you're letting air in through the throttle body (ie the ICV isn't really doing anything) and it runs alright.

[tmd7089]

yea but the thing is it dosent miss just at idle. If you sit there in neutral and fold the revs at say 2.5k rpms, it'll sputter. It seems like it runs ok when you are accelerating casually, but as soon as your at the same engine spped for too long, it starts to miss.

[mateo m3]

clean the icv

[tmd7089]

Well I just got done cleaning the icv and still the same deal. Running out of ideas at this point. I may try and see if I can get the plug wires from my sentra to work just to rule out the wires. Other than that, Im starting to run out of ideas.

[RsKeyz]

Have you checked your DME for water or corrosion? It's a longshot but worth a look... Even just a small amount of corrosion in there can make your car do some funny things. If that is OK, you might want to check your coil pack too. I also noticed that we haven't established if you're getting any codes or a CEL? If you aren't getting a CEL, check to make sure it's functional. I had my light burn out, didn't notice, so I didn't even know the car was throwing codes til I went through for inspection.

[tmd7089]

I checked the codes before and it didnt have any. However, there is some sort of electrical issue with the car as well. The dash lights and license plate lights are always on. There is a battery kill switch inside the car that you can disconnect so that the battery dosent die on you. So everytime I leave the car, I have to disconnect the battery, thus erasing any codes that would be stored and the car dosent run long enough for the car to throw any codes.

I'll make sure to check the dme for corrosion tho.

[RsKeyz]

Have you checked the trunk wiring harness?

[tmd7089]

I looked for corrosion in the dme and it looks clean. I didnt actually open up the tape on the trunk wiring harness but it looks ok otherwise.

[4bangin318is]

Check for breaks in your intake elbow..Over time they will become brittle and crack. ICV is a must too.