Everything started with a bad Crankshaft Sensor (the motor suddenly went off on city and highway speeds and won't restart for a while).
I put a new Crankshaft Position Sensor on, aligned it carefully several times. It fired it up but ran badly and went off after a few seconds. I put a new harmonic balancer on, aligned the Sensor again and fired it up again. It stayed on and everything felt well for the moment, so I started driving it. Sitting in front of a red traffic light, the idle speed was still a bit high, maybe 200 RPMs and the idle was a bit rough. When accelerating you can feel a misfire. The more the motor warms up (after 10 miles) the more you can feel it. Climbing up hills is more or less impossible.
I checked the Camshaft Position Sensor and checked the magnet on the Camshaft Timing Wheel - Everything looks fine.
I put new sparks, spark plug wires, a new ICM and coil pack on. - Noting changed.
I took the wiring harness that connects the ICM with the sensors and the ECM out of a good running car. - Nothing changed.
I installed a new Mass Airflow Sensor and Idle Air Control Valve. - Nothing changed.
I checked vacuum lines for cracks. - Found nothing.
I put a new ECU in. - Nothing changed.
I sprayed some brake cleaner around the intake and listened to higher idle speeds. - Nothing happened.
I checked the catalytic converter to see if it was clogged. - No, it's 3 years old and still fine.
Checked fuel pressure by pressing down the little valve in the fuel rail next to the injectors. - There is nice pressure on it (new Fuel Pressure Valve, Fuel Filter and Fuel Pump were installed 2 years ago).
I checked engine oil for whether or unburned fuel, debris, metal flakes or any kind of smell. - Nothing special in there.
Other options are maybe the O2-Sensor and the Engine Temperature Sensor for the ECU (both came new 2 years and 20,000 miles ago).
Mabey a bad injector. I got them checked at least 2 years ago.
I'm not able to tell you anything about codes at the moment, because I don't have a test tool for the OBD and the bulb for the Check Engine Light seems to be burned. I will put in a new one to see if I can pull any codes by get it blinking with a wire clamp.
Again, the symptoms:
- Rough idle.
- Deeper sound out from the muffler and a bad unburned fuel smell.
- Higher fuel consumption (maybe 25% more).
- Jerking and misfire under load.
- Sometimes jerking and scratching sound from the belt tensioner in idle speed when it misfires.
- 200 RPMs too much in idle speed and engine warm.
As you can see, I'm running out of options. Hopefully you guys have further ideas. Any ideas are welcome.
have the same problem?
Sunday, August 7th, 2022 AT 3:11 AM