Engine will not start when warm

JCJ15766

MEMBER
1994 FORD F-250
7.3L
V8
4WD
MANUAL
150,000 MILES

Truck listed above with a 460 v8 won't start when warm. It struggles to turn the crank unless you let it sit for an hour or so, and you cannot even jump it. I've replaced the starter, ignition coil, ignition module, battery, alternator, and solenoid.

Sometimes if I crank it long enough smoke will come out of engine compartment from passenger side fire wall area (starter side).

Sometimes if I run through the gears or roll the truck a short way it will start. This feels like some kind of electrical connection or flywheel position issue.

I don't want to spend any more money replacing things until I have a confident next step.

Please help!

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

We need to check the voltage at the starter on both wires when this is struggling to crank the engine.

https://www.2carpros.com/articles/how-to-check-wiring

I am thinking you have a wiring issue so that would explain the cranking issue and allowing it to cool down and it cranks fine.

The smoke that you are seeing if you crank it long enough is most likely a wiring issue or even the solenoid that is getting overheated. I would recommend not doing that because it will just burn up the starter.

Once we know what the voltage is when this is acting up, we will have a better idea on what to do next.

Please let us know what questions you have, and we can go from there. Thanks

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