In Reply to: WAs it hesitation? posted by Vladimir Vooss on August 24, 1999 at 01:14:54:
Seems to be some type of hesitation, but usually we get a flat spot at some point in the powerband and once past that point the car runs fine again. I would suggest that you give your car a good tune-up and start testing. If you don't have some basic equipment such as a good digital multi-meter (preferably with averaging), fuel pressure gauge, and spark tester go out and get them. They are necessities with these cars.
Your problem may be either fuel or ignition related. On the fuel side, if you notice that the problem gets worse as the level in the gas tank gets lower then it may be your transfer pump. Or it could be a lack of pressure due to a bad fuel pressure regulator. Or maybe your injectors are clogged. On the ignition side you should test for a good spark at the coil. You definitley need a spark tester for this to get the proper load on the coil. Then test the plug wires. And don't forget to read the plugs. They can tell you a lot about the condition of your engine. These are just some possibilities of many. My car had a hessitation in the low band that was cured with a new fuel pressure regulator and ICV.
How's this for a good weekend of fun?
: It occurred to me that the problem that's getting a tad bit worse with time may or may not be hesitation. When accelerating my '85 528e, it usually accelerates as nicely as these cars do. Then after a second or so, while my gas foot is still increasing pressure for more gas and continued acceleration, then some big hand, or something checks the acceleration - meaning, more gas is being given, the engine is trying to rev, but something is bleeding the strength of the acceleration. On short accelerations, the car will jerk backwards from the forwards "jolt" of the initial acceleration. After a very unpleasant couple of seconds, the bleeding acceleration effect lessens as the car reaches a shifting point, let's say, but it's definitely not accelerating freely. Is this what's called hesitation? And whatever it is, does anyone recognize this effect and what can I do about it?
: Thanks for any tips, and give me something to do this weekend.
: Vladimir Vooss