New E30 M42 owner has stalling problems

[G-Man]

Gang,

I need some help diagnosing an M42 engine stalling problem.  I'm a long time BMW owner, over 20 years of numerous 2002, tii and E3 ownership.  I've been searching for an E30 with M42 motor for some time and I saw this ad in the LA Craigslist that appealed to me.  

FOR SALE: 1991 BMW 318i 4-Door Sedan. $1500 OBO, new paint job, leatherette interior, Brand new Black paint (some minor scratches), impecable black interior, CD player, new speakers, STICK SHIFT

IMPORTANT: THE CAR DOES NOT RUN AND WILL BE SOLD AS IS!!! THE CAR DOES NOT START, AND WHEN IT DOES, THE ENGINE SHUTS OFF AT RANDOM TIMES. AIRCONDITIONING BROKEN. WE HAVE TAKEN IT TO 3 GERMAN CAR SHOPS AND BMW SPECIALISTS AND NONE KNOW HOW TO FIX IT. LOW MILEAGE (115,000). NEW TIRES, RECENT REPAIRS, NEW BELTS, NEW HOSES, NEW RELAYS, ETC.

Jack Fahuna owner of JFPRO BMW service in Van Nuys, my friend Pierre, (91 318is owner) and I went to the owners house weekend before last to check out the car. We brought along a spare battery and put it in the car and cranked it right over, the owners were speechless that it started right up. We drove it around, I liked it and I offered the owner $1200 which they accepted. PO threw all kinds of money at the car, the stack of receipts was incredible. To try to fix the stalling problem, a new fuel pump, fuel filter, fuel pump relays, was installed. PO said when they had it, car would stall and sometimes it would start immediately and sometimes take several minutes to restart.  We put a new battery in the car and had zero problems until yesterday. (had it for 9 days without any stalling problems).  Yesterday AM, I had the same stalling problems as the previous owners did.  The PO took it in numerous times to the dealer (Rusnak BMW) and independent shops and the problem would never duplicate while in for maintenance.  

I am now the owner of a 91 318i 4 door, previous one owner with only 118K on the car. It's black with a black interior and 5 speed. Any ideas of why it stalling while driving down the road or at a stop light?  Tank is 2/3's full.  When it dies while driving, it's sudden and when I down shift immediately after it stalls, it will start but that's like doing a high speed push start and dumping the clutch.  I am now scared to drive this car until I can get a better handle on what to look for in diagnosing the stalling problem.

After buying it last week,  the shocks/struts were original and needed replacing so some Bilstein HD went in along with new control arms and bushings. It has the original steel wheels with hubcaps, they have got to go, Bottle caps would look much better than the current setup. but I'm keeping my eye out for 15" & 16" wheels. It will need H1/H4 lights as well. the sealed beams will have to go as well. I've seen E30 owners putting in elipsoid lights, is this a retrofit from another BMW or would I have to just buy them?  I'll worry about the AC later, if it gets to 80 where I live, it's a warm day (N Santa Barbara county).

Woo-Hoo, this car is so cool. It revs so freely up to 6500, what a blast to drive (when it's not stalling).

Gordon
91 318i
74 2002tii, 5 speed, limited slip
73 Bavaria, 5 speed, Weber's, Bilstein's (for sale)145K miles
70 2800, Euro spec, 95K original KM's
96 4Runner, parts hauler

[johna]

I had what sounds like a similar problem. Turned out to be the main voltage input wire into the fuse box had come really loose. I was surprised the car ran at all.

[Jtuner]

Gosh, really you can replace parts, and replace parts, and replace parts, etc etc.. What you really have to do is just start somewhere with a DVOM, and voltage drops and compare to specs.. It seems like it could be an electrical problem, so start at the transfer pump and back-vdrop.. you gotta use the process of elimination! otherwise, check the continuity in your coolant temp sensor by putting it in whatever temperature water spec says, and testing the ohms.. My 318 was doing this similar type of thing (not as extreme) and I just threw in a new coolant temp sensor and life is good
Now this does sound like another recent car me and my brother were working on, an 86 325es that was having very similar issues.. I could drive it for days with no problem, nice smooth pull to redline, and it was stellar,, then the next day I'd turn the key and it'd kill.. then itd start and die,, etc.. SO it ended up being a very VERY sludged gas tank, which in turn sludged the gas lines, which sludged the fuel rail, and in to the head where it made a valve or two stick on occasion(thus the stalling, dieseling, and dying..) Do you know if the car sat for a long time before you bought it, with a low amount of gas in the gas tank? Lets fix your car!!

[FL318is]

Welcome to the M42.  I just got mine a little over a month ago.  Did not have your problem but did have a couple.

The guys on this board successfully diagnosed and encouraged while I went through each issue.  I have learned that sometimes the big problem with the M42 has the simplest solution.  Stay with it and these guys will get it fixed.

[Febi Guibo]

off the top of my head, it sounds like:

- PO had weird problems
- New battery solved the problem
- 9 days later, problem comes back

I would think about really checking the alternator out; also there's a ground wire from the alternator to the engine block; the alternator vibrates, the wire often breaks (it's a big 0 gauge wire) or comes loose.

[thumper3ld]

Since people are suggesting electrical, I would also check the battery ground in the rear. Mine was damn near broken through at one point.Dont think this would cause ur symptoms, but it doesnt hurt to look.

[Jtuner]

Since people are suggesting electrical, I would also check the battery ground in the rear. Mine was damn near broken through at one point.Dont think this would cause ur symptoms, but it doesnt hurt to look.

/agree,, if it got better when you changed your battery, then got worse, this could be a very simple thing,, check those cables out good! I also agree with Febi, that alternator wire can be tricky.. if its hanging on by a thread, or not at all, that could cause such issues... Good luck with it man :cool: