Questions and Answers
BMW 328i DTC #DE
Q. Hi Vincent, I own 1998 BMW 328i, 50,000 miles. My check Engine light came on. I checked it with scanner I purchased from Peake research. The scanner registered Code # DE which in their code chart means, (Time to close loop temperature too long). I do work on my car, with the help of the shop manual, I enjoy it as a hobby.
I don't understand what this code mean, I noticed my car temperature gauge doesn't worm up fast enough. Does this code mean the thermostat needs to be replaced?
The service manual that I use is Bentley, but it's not listing the code interpretation for OBD II. I expected the publisher to include that in his manual. They do have a list of codes, and what they mean for OBD I, but not OBD II. Please help.
Thank you,
RafaelA. Long answer: Since the PCM uses engine temperature to go into closed loop (O2 sensor kicks in). The pcm gets engine temperature from the Coolant Temperature sensor. So if the thermostat is stuck open, and it takes a long time to get to normal operating temperature, it will throw that code.
Short answer; Yes, you need to replace the thermostat.
