GS400 1998 Random no-start <solved>

[Spinnetti]

This is a transplant. Car has been running great, instant start, runs smooth etc... Suddenly I'm getting no-starts randomly. It cranks fine, and starter spins over quickly, but doesn't catch or catches and dies right away. Seems to be totally random. Either it starts immediately or not at all. Any ideas? I have a fuel pressure regulator on it and its showing 43psi regardless of start or no start. I got a new ignition switch, but that didn't seem to have any effect.

Ideas?

 

[George_R]

There are countless options
Just one: crank position sensor wire has been damaged
Valid reasons also include wrong phase of moon, or retrograde venus, accounting for engine age and zero input data given by you

 

[Spinnetti]

Thanks(?) zero input data? I don't know what to provide. Its got the full engine, trans and wiring from the GS, so essentially a stock 1998 GS400 from an operational standpoint. It has a kill switch (otherwise the battery will drain for other reasons) so I don't have any codes. I'll hook it up to a tender after I run it next and see if I get any codes. I wondered about crank position sender wire - no idea where that is, so will look it up. thanks.

 

[Spinnetti]

ok, no codes so far. Fuel pump is new. CPS wiring looks ok. Will pull it to see if gunked up.

 

[George_R]

Scan tool => real time data => compare RPM reading in normal and no-start condition
Then proceed to usual checks like fuel spark etc

 

[Spinnetti]

- Swapped out the MAF, no change
- Swapped out the ignition switch, no change
- Changed the key battery, no change
- CPS seems fine, no gunk on it, wiring seems good.

HOWEVER.... I do have Prius EPS on this car, and I THINK what might be happening is some times the voltage is pulled low by the EPS energizing preventing the ECU from running the car. Disconnected that and it seems to start normally now. Will rewire the key on power for that and see if that does it.

 

[Spinnetti]

Thanks for the replies... figured it out. EPS was pulling down voltage. Rewired EPS to not power up until start and alls good.