I’ve searched a bunch of different threads but nothing shows the same symptoms that my car is showing. Basically I go out, turn key on, and try cranking over but the PFC Commander shows no rpms, just stays at 0. However sometimes if I leave the key in the on position for a couple minutes and then crank it over it’ll finally start. Battery shows good voltage, new plugs, new wires. Already did the deflood procedure a couple of times. Fuel pump is aem 240lph rewired to get constant 12. When it is running it runs great, aside from slight hesitation issues I get every once in awhile but I believe that’s unrelated. Any ideas and help would be much appreciated. Again I’ve searched a bunch but couldn’t find a thread that would give me some troubleshooting tips. Car is a 95 RHD with slight mods, intake, down pipe, cat back, and pfc.

 

Check the wiring at the cas plugs. Leaving the key in and it just suddenly working is really odd but maybe the wiring has something funny going on. If the commander isn't registering rpm then starting with the cas makes the most sense. Its also not unlikely it could be a problem with the pfc itself.

 

should I be mainly just testing for resistance? And then the gap size with a feeler gauge?

 

You can but I meant just literally look at it.... like just put eyes on the wiring actually at the plugs on the cas. Touch them as well and just verify their integrity.

 

alright I’ll take a look, thank you!

 

Wondering if its a few separate issues. What tune is on the PFC?

When it does finally start, are you getting a lot of unburned fuel/smoke?
Does it start easier after the deflooding? Wondering if you have a stuck or leaky injector that might be causing the start issues. Mine was harder to start and was flooding. I ran a few bottles of Techron fuel cleaner through and it ran, idled better and got rid of a lot of the hesitation.

Are you using rotary plugs or standard plugs?

 

stock base map on pfc, I’m not getting any black smoke or any odd smoke coming from the exhaust, I get white smoke on startup but this goes away after it warms up, thinking normal no big deal, and I wouldn’t say it starts any easier after a deflood. I will say that I have thought about either clogged or leaky injectors however I’m running more rich than I am lean which steers me away from clogged injectors. Notice it would go slightly more lean during the intermittent hesitation, +1 or +2 from where it’s normally at around 12. I know.. it needs a tune badly just waiting on my cable to come in. I’m hoping if I still have these issues after I try and put new wires and connectors on the cas sensor that a tune will clear it up but I’m not too sure. I still think the no start and hesitation issues are separate. Plugs are 7s and 9s

 

no engine speed during cranking is like a fundamental issue with your wiring.

What is the history of the vehicle? Did someone "simplify" the harness or is it a high mileage one that's totally melted/baked?

 

sat in a auction lot on mainland japan for awhile before getting shipped to Okinawa, I then bought it from the dude who shipped it, 128k km so it’s not super high mileage

 

My CAS wires broke right by the connector. The worst part is that the wires broke inside of the wire insulation, so it wasn't detectable to the naked eye. Another thing I've seen is the OMP wires that hang right above the trigger wheel fell into the way of the CAS sensors and caused an rpm signal loss. A quick little hail Mary that you can do, is to have someone crank the car and stare at the PFC while you wiggle the CAS wires. If it starts picking up an RPM signal, you have a wiring problem in that area. If that doesn't work, bust out the ohm meter and measure the resistance from the CAS to the ECU. You probably have an open circuit somewhere in there. The CAS wires also ground by the ECU, so I'd check to make sure that is grounded properly.

 

The good ol' fashioned "wiggle it a bit". : )

 

I got a new connector pigtail in the mail the other day so I’m going to splice that in and see if it was a connection issue. But yeah, I still need to try the wiggle test lol thanks for the help!

 

For anyone following this, I got a new sensor and it fixed the issue, however the old one tested out with good resistance so I’m not sure what actually fixed it.