'88 190E 2.6, 84K miles... after a one hour freeway drive and one hour stopped the engine cranked but would not start. It initially felt like no spark.

After several more attempts, it started, but ran very rough for a few seconds while I rapidly pumped the throttle, then it smoothed out, and I was able to drive off with no further issues.

The next morning on a cold start, it cranked-started-died twice. On the third try I rapidly pumped the throttle when it fired, and it kept running, but very roughly for a few seconds before smoothing out with normal fast idle, and I was able to drive off without further issues. So now I suspect it's not getting enough fuel while cranking, hot or cold.

Ambient temperatures were in the 60s-70s...no check engine or ABS warning lights, so I don't suspect the OVP, which is original.

The other suspects are fuel pressure regulator, fuel accumulator, and fuel pump relay.

For a number of years on a hot restart it will often crank-start (on all six) -die, but I figured out how to work around this by just giving the throttle a kick once it fires, which keeps it running and it quickly assumes normal idle. Cold starts up until Saturday were normal - fired quickly and assuming about a 1200 RPM stable idle in 60-70 degree temperatures.

Does anyone have any suggestions on how to go about troubleshooting this problem? I've never done anything with the KE-system other than check the duty cycle (no adjustment required) and changed the fuel filter with the last time being 9000 miles ago, and the old filter was not at all clogged.

Duke