Won't start! Will start if I coast down hill and pop clutch! Options

[Ian Stott]

As described! What is up with this situation? Engine runs beautiful when warmed up, will restart no problem if It has been shut off for even a few hours. Kudos to the battery and starter as I have tried to start it normally when it has been sitting for a few days, won't catch, thank goodness I live on a hill, coast down the hill a bit, put her in 3rd gear pop the clutch and vrooom! Have done this 6 times now!

Ian Stott
Moncton
Canada

[Spoke]

So it doesn't start when cold but will start if you push/coast start it?

What are the differences in both methods?

Engine speed:
Starter: slow
Coast: slow

Ok, so engine speed should not be the issue.

Extra fuel when cranking:
Starter: YES, the ECU extends the injector pulses to put in more fuel when cranking.
Coast: NO, the ECU sets injector pulse width by temp of engine/ambient/CHT

Here's a difference, pulse width during cranking may be flooding the engine. Maybe not. Does the engine run rich? Have you had the AFR checked?

Voltage at coil:
Starter: Voltage at coil will be lowered by IR drops in the wiring applying less voltage at the coil.
Coast: Voltage should be close to battery voltage since starter is not cranking.

Check the voltage at the coil with a voltmeter when cranking. Measure from coil + wire to engine case ground, not the battery ground. Also, pull a plug wire and install a spare plug on the wire and ground the plug and look for spark when cranking.