BMW no acceleration and shaking

driving
acceleration
bmw
gasoline
pump
528

#1

I have a 1999 BMW 528i, I got used 4 years ago. In the last 2 months, I put on about 8K miles on it. Now it is up to 125K miles. I have been having two problems, I think are related, since they feel the same but I am not sure.



The first is that when I am on the highway and want to accelerate from say 40 to 60, I hit the gas and the car shudders as it tries to accelerate, it has done this for the last 4 months, occasionally, like once a week. The shudder feels like a piston is missing, it is a really hard, ongoing shake, the car will accelerate, slowly and then when I back off the gas the shudder will go away, and then I can accelerate without problem.



The second one happened for the second time on Friday. I tried accelerating, like above, however the shudders stayed for as long as I was pushing the gas peddle down. If I would let up from the peddle, to keep the car at a constant speed, it would be fine, but any acceleration would make it shake. I pulled over to the side of the road, turned the car off and on and I was fine I ziped back into traffic … For about 2 miles when it started again. I then pulled to an exit, went to a gas station, opened the hood, looked for the large switch that would say ?turn problems off?, but could not find the switch, so I filled up the tank (I was close to empty) and tried again, there were no problems for the remaining 40 miles back home. I am pretty sure that the last (and first) time this happened it was also low on gas, and turning the car off and going to a store made the problem go away.



When the shudder is sustained, the check engine light comes up, during the problem, but does not stay on after I turn off and on the car.



My thoughts are that this is a gas getting to the piston problems, and that it could be a fuel pump, fuel line or computer problem. Could this be a tran$mi$$on thing?.. I am not sure I want to put more money into this car?



Any ideas?

N2L


#2

Since the check-engine light came on, the first step is to have the codes read. Many auto-parts chains will do this for free.


#3

Have the codes read. Most parts stores will do it free. The codes may give you some indication where the problem lies.

I can’t imagine there’s anything inexpensive to fix on this car so if you’re not sure about putting money into it you may have a conumdrum on your hands.

Has the fuel filter ever been replaced?

Have you checked the transmission fluid level? Is it even possible to check the fluid on this car?


#4

“I am not sure I want to put more money into this car?”

I think that you may have answered your own question.
If you have not done the extensive (and expensive) maintenance that is due or–more likely–overdue, this problem will not be resolved easily.

Step #1 is to have ALL of the 120k mile maintenance done. This will likely include replacing the spark plugs, all filters, and all fluids. After doing the necessary maintenance, have your mechanic do a scan of the car’s OBD system.

While there is a good chance that simply doing the required maintenance will take care of the issue, even it the problem remains, it will be much easier to diagnose once the car’s essential maintenance has been attended to.


#5

The local parts shops did not have the code machine for the BMW (they mentioned an adapter they did not have). It is with the mechanic now. I have kept up with the 15K/30K mile maintenance program with BMW. I have brought it to the same non-dealer shop, who specializes in BMWs, and he has fixed all the things that have broken (computer, radiator (once the radiator, once the supplemental tank), door window guides (3 of the 4 windows), wheel rims & break pads). I told him about this shuddering problem when it was only the first problem, and he said he worked on it, but there was no line item on the bill about it. I am trying to figure out what to expect…


#6

These are great cars, no reason at all to suspect the transmission. 125K is simply “break in” mileage. You may be trying to make chicken soup out of chicken feathers here (check Service Information first with any BMW driveability sympton).

I am again thinking throttle body as there are known issues that fit your symptons. The info is in a Service Information bulletin.

I went and looked for you. Your mechanic should be familar with
SI 12 02 97 DME reprogramming

SI 12 07 99 Motor drive throttel valve

BMW SI’s are a bit difficult to read (they are really for those trained in BMW speak)

Don’t assume that because you car fits the SI info that you have postively identified the problem, it is merly to give you a place to go to when you examination of the fuel and ignition system does not reveal the cause of the concern.

I have serviced hundreds of this model BMW and they had very few driveability issues, they are not “lemons”.


#7

Well the answer was: 3 burnt out spark plugs!.. apparently though I have taken the car to the same guy for 50K miles (and 4 years) he did not keep track of the spark plug changes, I would take it in ever 15K miles and annual inspection and just say “do the maintenance”… Was that my responsibility or his?


#8

I am not sure whose responsibility it is. As far as I know and what my mechanic tells me (I own a 2003 525i) the car runs on long-lasting high performance spark plugs that are expensive to replace but in exchange last 10s of 1000s of miles. So whenever I bring it for the annual checkup and talk about spark plugs he tells me I don’t need them. Sounds to me like you bought the car used and it might not have been equipped with these long-lasting spark plugs. In that case the mechanic could of course have checked (his fault) but then again: They usually don’t need replacement.

These cars are bullets, especially when it comes to engines and transmissions. You shouldn’t expect any major problems at this relatively young age.


#9

There is no place to go but an argument with someone about who’s responsibility it is to make sure the plugs were changed BUT I would say it is your responsibility when writing in for help to say at least "I don’t know what has really been done in the area of maintenance as I just say “do the maintienance”.I feel you have a responsibility to us here at CT,not to waste our time.

Now why this mechanic would not sieze upon an opourtunity to do a plug change before it turns into an issue when he knows he has a customer who chooses to delegate this responsibility to him is also a mystery. I would be very suspect as to this mechanics ability to not miss other things.

At least i did tell you to do the easy stuff first.