Strange behaviour...
Greetings all,
I'm new on the forum, but not to the BMW world. I've owed a couple E30s and one E34. The car in question is my daily driver 84 318i. I've recently passed the hideous CA smog test thanks to a friend. The downside, my baby now runs like crap. Before the smog, I had the AFM spring wheel dialed a few teeth richer, and the computer idle bypassed, now it's set back to stock. I now have a consistant rhythmic hesitation that is most notable when the engine is cold. And by notable I mean it's barely drivable until it warms up. Cold start is perfect, cranks right over and runs, however as the engine speed comes down (about 10 secs or so), it sputters and dies unless you practicaly floor it. Even after it's warm, the acceleration is not linear at all, it's still jumpy and not too powerful, not that the M10 is a beast anyway. It has a 5 speed manual, and I have replaced many, many parts. I'm trying to get it to run stock again (better mileage). Recently I have replaced the cap, rotor, plugs, AFM ($$$), fuel filter (correct OEM parts), and last year I replaced the ignition coil, wires, starter, pressure regulator and many other non engine parts. I have tested most everywhere on the intake for vac leaks with TB cleaner. I also have pulled and cleaned most of the ground points under the hood and the one under the steering column. I'm getting tired of replacing everything and having little effect. I did read a bit on this site about having excess play in the distributor shaft. I have about 3/16" play up and down. Also the main fuel pump makes a noticable buzz from under the car. I have put my ear to the tank and heard that one working as well. I do have two newer pumps on the shelf from my old 318. I just don't want to replace them unless necessary. Another note, I ran the car this morning, and as it would idle and stumble, I would spray a mist of TB cleaner in front of the air box and it would smooth out for a second and then go back to its behaviour. I can only guess it isn't getting enough fuel. However, I'm hoping someone here can help shed some light on my baby's bad temper. Thanks in advance.
Cheers,
Matt
I'm new on the forum, but not to the BMW world. I've owed a couple E30s and one E34. The car in question is my daily driver 84 318i. I've recently passed the hideous CA smog test thanks to a friend. The downside, my baby now runs like crap. Before the smog, I had the AFM spring wheel dialed a few teeth richer, and the computer idle bypassed, now it's set back to stock. I now have a consistant rhythmic hesitation that is most notable when the engine is cold. And by notable I mean it's barely drivable until it warms up. Cold start is perfect, cranks right over and runs, however as the engine speed comes down (about 10 secs or so), it sputters and dies unless you practicaly floor it. Even after it's warm, the acceleration is not linear at all, it's still jumpy and not too powerful, not that the M10 is a beast anyway. It has a 5 speed manual, and I have replaced many, many parts. I'm trying to get it to run stock again (better mileage). Recently I have replaced the cap, rotor, plugs, AFM ($$$), fuel filter (correct OEM parts), and last year I replaced the ignition coil, wires, starter, pressure regulator and many other non engine parts. I have tested most everywhere on the intake for vac leaks with TB cleaner. I also have pulled and cleaned most of the ground points under the hood and the one under the steering column. I'm getting tired of replacing everything and having little effect. I did read a bit on this site about having excess play in the distributor shaft. I have about 3/16" play up and down. Also the main fuel pump makes a noticable buzz from under the car. I have put my ear to the tank and heard that one working as well. I do have two newer pumps on the shelf from my old 318. I just don't want to replace them unless necessary. Another note, I ran the car this morning, and as it would idle and stumble, I would spray a mist of TB cleaner in front of the air box and it would smooth out for a second and then go back to its behaviour. I can only guess it isn't getting enough fuel. However, I'm hoping someone here can help shed some light on my baby's bad temper. Thanks in advance.
Cheers,
Matt
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