Alright folks, so have a 81k mile 1989 325iX with stock M20B25 and have the following symptoms:
- Car idled poorly and had light black smoke coming out of the tailpipe during cold start today in 80-ish degree weather. This previously never happened. As the car warmed up, the black smoke and poor idle went away (I’m thinking this happened when the O2 sensor got hot enough).
- When fully warmed up, the car intermittently throws a Check Engine light with code 1222 is thrown at or below 1500 RPMs. The car also struggles to maintain a stable idle and there is a noticeable loss of power below 1500 RPM. If I’m at a stop and give the car gas (normally opening the throttle 25-70% and revving the engine to 2000-2500 RPM), the Check Engine light disappears and the engine runs a lot better
- The car previously had hard starting issues when the weather was warm and I just drove it around and let it sit for like an hour (coolant temp gauge was usually between the blue zone and the 1/4 mark when this happened). Now if I let it sit for an hour after driving it, it will start then die unless I give it a good amount of gas for like 20-30 seconds.
- Before all of these symptoms happened, the car had a steady 500 RPM idle with light vibration but otherwise drove fine. This doesn’t sound right to me as the Bentley says idle RPM should be around 750.
Based on the symptoms I’m seeing, it sounds like the car is running rich. Any idea what the culprit is here? I’ve heard the 1222 code could be a bunch of things and don’t want to just throw parts at it. My guess is the ignition system is slowly failing. Don’t see any maintenance records indicating a replacement in the set that I have. Anyone have the same exact set of issues? If so, what was the cause?
So far I have diagnosed to coolant temp sensor and it checks out okay. Checked the FPR line to the intake manifold and don’t see a drop of fuel coming out of it. Will be diagnosing the ignition system when the weather gets better (no garage)
- Car idled poorly and had light black smoke coming out of the tailpipe during cold start today in 80-ish degree weather. This previously never happened. As the car warmed up, the black smoke and poor idle went away (I’m thinking this happened when the O2 sensor got hot enough).
- When fully warmed up, the car intermittently throws a Check Engine light with code 1222 is thrown at or below 1500 RPMs. The car also struggles to maintain a stable idle and there is a noticeable loss of power below 1500 RPM. If I’m at a stop and give the car gas (normally opening the throttle 25-70% and revving the engine to 2000-2500 RPM), the Check Engine light disappears and the engine runs a lot better
- The car previously had hard starting issues when the weather was warm and I just drove it around and let it sit for like an hour (coolant temp gauge was usually between the blue zone and the 1/4 mark when this happened). Now if I let it sit for an hour after driving it, it will start then die unless I give it a good amount of gas for like 20-30 seconds.
- Before all of these symptoms happened, the car had a steady 500 RPM idle with light vibration but otherwise drove fine. This doesn’t sound right to me as the Bentley says idle RPM should be around 750.
Based on the symptoms I’m seeing, it sounds like the car is running rich. Any idea what the culprit is here? I’ve heard the 1222 code could be a bunch of things and don’t want to just throw parts at it. My guess is the ignition system is slowly failing. Don’t see any maintenance records indicating a replacement in the set that I have. Anyone have the same exact set of issues? If so, what was the cause?
So far I have diagnosed to coolant temp sensor and it checks out okay. Checked the FPR line to the intake manifold and don’t see a drop of fuel coming out of it. Will be diagnosing the ignition system when the weather gets better (no garage)
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