320E36
01-04-2007, 08:25 PM
Hi folks,
Here's an interesting one. On a '93 320i, when driving at highway speeds (120 k/hr approximately), the engine starts to lose power as if an engine brake was being applied or something. Giving more gas seems to clear it or, if I don't add more gas, the car seems to clear itself and then accelerate as if to catch up. This happens very often, but not consistently.
Here's the history. A few months ago, I failed an emissions test. After studying the readings and making assumptions why it failed, I replaced the plugs (ended up buy from dealer since all others were out of stock, and i was out of time), I also replaced the O2 sensor with a univeral one (2 white, 1 black, 1 grey wire). Since then, I've had some serious and intersting performance issues. For a while, when I was starting from a stop, the car would seem to bog down, backfire from the intake area, and then seem to clear itself and go normally. This stopped recently, but I'm still getting the highway symptoms.
After no luck doing my own diagnostics, I took it to the dealer who found water in the DME/ECU unit, and recommended replacing the O2 sensor and air flow meter. The DME was dried out which seemed to help slightly.
I'm assuming that the univeral O2 sensor is not the correct type (zirconia instead of titania), or, since the highway symptoms are intermittent, a loose wire somewhere?
Thoughts?
Here's an interesting one. On a '93 320i, when driving at highway speeds (120 k/hr approximately), the engine starts to lose power as if an engine brake was being applied or something. Giving more gas seems to clear it or, if I don't add more gas, the car seems to clear itself and then accelerate as if to catch up. This happens very often, but not consistently.
Here's the history. A few months ago, I failed an emissions test. After studying the readings and making assumptions why it failed, I replaced the plugs (ended up buy from dealer since all others were out of stock, and i was out of time), I also replaced the O2 sensor with a univeral one (2 white, 1 black, 1 grey wire). Since then, I've had some serious and intersting performance issues. For a while, when I was starting from a stop, the car would seem to bog down, backfire from the intake area, and then seem to clear itself and go normally. This stopped recently, but I'm still getting the highway symptoms.
After no luck doing my own diagnostics, I took it to the dealer who found water in the DME/ECU unit, and recommended replacing the O2 sensor and air flow meter. The DME was dried out which seemed to help slightly.
I'm assuming that the univeral O2 sensor is not the correct type (zirconia instead of titania), or, since the highway symptoms are intermittent, a loose wire somewhere?
Thoughts?