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halifax318ti
07-23-2008, 05:05 PM
I have a '98 318ti with the M44 engine in it with roughly 180,000 kms on it. Have started to notice that it hesitates during accelearation from a dead stop. As well, when I am on the highway at cruising speed, it will every so often hesitate a bit. It doesn't do it all the time and it isn't that severe but would like to get it diagnosed before it gets worse.

Not sure if anyone else has had this problem but any insight would be helpful. The engine light hasn't come on as of yet.

b.u.ti-ful
07-23-2008, 05:59 PM
Could be a lot of things.

First check for any obvious air leaks at the throttle body, intake manifold and associated hoses.

Then look at the spark plugs and see if any of them look particularly sooty or oily.

If these things look okay the next thing to examine is fuel delivery such as dirty injectors.

This should get you started.

madfronter
07-23-2008, 06:15 PM
Is your CEL on? If so you should have the codes read so you can narrow down the issue. Sounds like it could possibly be the camshaft position sensor. Those are the same symptoms I and many others experienced when theirs went bad. Though I would take a look at your plugs, wires, ignition coil pack, vacuum leaks...

Marv17
07-23-2008, 06:18 PM
check your ccv (crank case valve). i had a bad one that made everything rough.

Jcompo
07-23-2008, 06:22 PM
I had that problem, it was a torn vacuum hose.

Caliburnes
03-10-2014, 05:18 PM
I understand this thread is way old but I am having this issue and it is bad. I had posted another post Thinking it has something to do with my ASC but not sure. The ASC light is on but I'm not sure its related anymore. The car doesn't hesitate so much on take off but it does while cruising sometimes so bad I loose speed. I thought it was the ABS acting up cause the RPMs dont change. But on applying the brake and throttle together it still does it. I was driving back from salt lake to Idaho so I decided to change the spark plugs just as a precaution but no change. I did add some Lucas fuel injector cleaner before I left to and about half way through my trip the hesitation stopped but then came back again not as bad. The hesitations would happen during acceleration even slight so going up a minor grade or even flat it would happen and get worse up a big grade and not when coasting down a hill. I'm pretty sure the plug wires are original cause they are BMW but if not they are at least 70K old. So I'm thinking either fuel pump or injection or wires? Lots of this I didn't notice on my drive there cause it wasn't as bad but was way worse on the way home other than when it sort of stopped. I just dont know if its necessary to replace fuel pump if wires are easier. Long explanation but I'm still also concerned about ASC light to maybe its the power limiting valve before throttle?? Any ideas??
Oh as an edit the can sensor I replace a couple thousand miles ago but used cheaper aftermarket one cause thats what I could afford at the time.