Rough Ride! 97 328i

[lukyjoe31]

I've recently reached the age of man hood (in my mind) and decided to get my vehicle back to tip top shape. I've gone through the cooling system sage and replaced the radiator, water pump, and the external coolant thing that allows you to poor the coolant in. The ignition cylinder broke and I replaced the the cylinder and housing. So now I am trying to get my car to run as smooth as possible in order to prevent another roadside breakdown. I notice many things wrong: when I press the gas pedal down it feels heavy and a little harder than normal to press down. The second I press the gas pedal down the RP M's go up and than the car begins to move after the RP M's have gone up some (that could be normal). The second I release the pedal, the car feels like it is doing an extreme engine brake, but my car is an automatic (not sure on that one). Also the low humming noise that comes with pressing the gas pedal and the RP M's going up is much louder than normal. Now the problem only occurs when I press the gas pedal, of course I haven't tried to listen with it sitting in an idle position. Any help would be perfect. I changed the air filter and spark plugs today.

J-smooth

[Wayne 962]

Hmm, lots of questions here. What's an ignition cylinder? These cars have six individual coils for each cylinder.

The problems your describing sound almost like a transmission problem, have you checked the fluid level in the auto tranny? We have a tech article on this in our tech articles section (click at the top of this page).

-Wayne

[Jeron]

The ign cylinder is where u put the key to start the car. Wayne, I'm surprised you can even type at 2am, I'm usually stumbling toward bed at that time.

My guess is tranny or torque converter.

[lukyjoe31]

I talked with a friend at my church who turned out to be a BMW Mechanic. The downside is that he is not allowed to work on BMW's due to a contract with the shop he works at. Although he is allowed to answer questions and give me his opinion and he suggested to have the transmission flushed and maybe replace the filter. Im afraid that it will cause more problems with my transimission in the long run. What do you think?

[Manolito]

BMW says that the tranny fluid in your car is 'permanent'. Bunk.

I changed tranny fluid my wife's '97 328 at 100k miles and it significantly improved the way the tranny worked. The car is now my daughter's car and has 140k on it.

You have probably noted that these trannys work much differently when cold than when hot. When cold, they are much more hesitant to shift, so you get engine braking when you back off the gas rather than an upshift. It should stop doing that after a mile or so.

Change the fluid and see what happens.

[Manolito]

There were more questions in your original post that I did not address.

You can turn the throttle valve by hand and figure out why it is difficult to press the throttle. Could be a worn cable housing. On some cars, there is a second cable that runs from the throttle plate assembly down to the tranny. It's function is to force an immediate downshift when you floor it. I don't recall seeing this secondary cable on the BMW, but if it has one, that would be the most likely suspect in a stiff throttle.

Regarding the louder than normal engine noise, put the car on ramps, start the car. and then quickly before it get too hot, hold your hand near each of the joints in the exhaust manifold. You are looking for an exhaust leak. Also check to see if the noise is blowing back through the air pump. The air pump is that vacuum cleaner-like motor on the passenger side back near the firewall. Its air inlet is a hose that goes over the passenger side shock tower.

While you are doing routine maintenance, you should clean the throttle plate assembly and inspect all the inlet air tubes carefully for cracks. The car is 11 years old and plastic parts are starting to get brittle.

[Jeron]

If you are already having tranny problems then you nothing to loose by changing the fluid.

[lukyjoe31]

Took the car to a Transmission Show because the mechanic said he would look at it for no charge. A WEEK LATER!!! He calls and says he thinks it is the Throttle Position Sensor but isn't sure. I think I am going to take my car back and replace the TPS because there is no telling how long my car will remain at his shop if I let him do it. If the problem persists than I will take it to a reliable mechanic who did marvelous work on my drive shaft. Any suggestions on how to handle this situation?

[coolbear1]

If you have a bad TPS, your check engine light will be on and a fault code will be stored in the ECM, P0222 thru 229.
You can check the TPS with a digital OHM meter. you should have 4,000 (4kOHMs) between the top and bottom terminals with the trottle at rest.
Connect the meter to the bottom and middle terminal and open and close the throttle.
The resistence between these terminals should ramp up and down between 1 and 4 kOHMs from full closed to full open.
Hope this helps.
Good luck.