Posted by Marlen Padberg on January 28, 1999 at 15:13:57:
In Reply to: Loss of Power while running posted by Chandler Ogden on January 27, 1999 at 22:28:56:
When was the last time you ran a bottle of Injector cleaner thru? I've had dirty Injectors give miserable performance, but symptoms are usually different from what you're suffering. Like Troy says, if your battery is not holding its charge like it used to, and the ignition is not getting enough voltage, this leads to a weak spark and at low RPM situations, you would have exactly that. I had my alternator fail on me once (in a different car), and as I kept driving, I had the same condition, and it became more pronounced as the battery drained. Finally, car stalled and that was it. Swap alternator, charge battery, good as new.
: Hey-
: I would appreciate a little diagnois/troubleshooting help...I was driving my '85 535i on a 200mile trip today, and had a wierd mechanical problem..
: I drove the first 45 miles fast, with no problems. I then stopped, picked up a friend, and began the next leg of the trip. After a short while, at 65-70 mph, 2-3K rpm, the car stuttered and lost power. I reacted by downshifting and pumping the pedal a bit, and it cleared up and drove fine. Seemed like a slug of bad gas or something... This happened sporatically for the rest of the day, and each time, it would seem to clear up with more gas/higher rpm. It seemed to happen when the motor was more unloaded and at lower rpm, such as when I had backed off of the throttle and was just mainaining speed.
: I filled 'er up last night, and thought I could have gotten some bad gas, so I added some fuel additive. This does not seem to have made a difference.
: My initial guess was fuel filter or something wrong with the fuel pump. On further thought and consultation with a motor-head friend, I am thinking it may be a partially plugged catalytic convertor.
: The car idles fine, and runs and accellerates OK otherwise.
: Before I sink a bunch of cash into a catalytic convertor or into random part replacement, I am looking for opinions...
: Any guesses on what the problem could be, or what a good troubleshooting approach would be?
: Thanks!
: Chandler