M117.963 Low Power Misfire at 3500 RPM

[oden007]

Howdy, I have a 1985 G Wagon with a M117 swapped in. Replaced fuel pump, vacuum hoses, and intake boot. The truck sat for at least 5 years so I am looking at running fuel system cleaner and hoping to free up the fuel distributor a bit.

Should I just throw parts at it, new plugs, ignition systems, injectors, etc.

Other issue is hot start issue, I have to restart when hot by pushing the air meter plate all the way down and then it will fire up with a stumble and then smooth out.

A lot of issues, but the truck is to cool to give up on.

New here, any help on where I should start is appreciated.

[Sugar Bear]

Hard to say for sure but since it sat and you have to push on the plate for hot starts, I'd try BG fuel cleaner if you can find it, Techron or LiquiMoly in multiple strong doses with premium Top tier fuel.

Plugs are cheap and looking at them might give a clue so I'd put standard Bosch or NGK's in it too. Stick with normal old school plugs not fancy expensive upgrades.

Good luck!!!

[porkface]

hot start could be a fuel pressure issue. put gauges on it and check the pressures, cold and hot.

for the misfire, i'd scope the ignition and see. could be the coil cutting out.

[Sugar Bear]

Scoping the engine...good idea...for a DIY at home I've had success using a timing light and looking for intermittent flashes. Of course an oscilloscope would be far superior.

Good luck!!!