Hi everyone,
I have a warm start issue with my Mercedes 190E 1.8 automatic. It has the M102 1.8 engine and a 4-speed automatic transmission.
The problem has been there for quite a while now. When the engine is warm, it can be very hard to start again. For example today, after sitting for around 30 minutes in the sun, the engine temperature was still showing over 80°C. I had to turn the ignition off and on several times and give it some throttle before it finally started.
I attached a video clip where you can hear the issue pretty well. You can also hear a weird noise when I turn the key to position 2, before actually starting the engine. It sounds like something is briefly stuck, blocked, or struggling, maybe somewhere near the fuel pump area, but I’m not sure. The fuel pump itself was replaced in 2024, so I’m a bit lost here.
Relevant work already done:
- New air filter: 01.09.2024
- New spark plugs: 01.09.2024
- New fuel filter: 18.09.2024
- New fuel pump: 18.09.2024
- New ignition leads: 28.12.2024
- New distributor cap: 28.12.2024
- New engine mounts
- New transmission mount
- New thermostat: 16.04.2026
- New distributor rotor: 16.04.2026
Current mileage is around 234,105 km.
The car is a Mercedes 190E 1.8 automatic with the M102.910 engine and 722.420 automatic transmission.
Does anyone have an idea what could cause this? Could it be fuel pressure loss, the fuel accumulator, injectors, EHA, cold start valve, ignition-related, or something else in the KE-Jetronic system?
Any ideas or things I should test first would be really helpful.
Thanks!
Tom