mluu92

New day new issue it seems….


Today I drove the car home from the workshop I have been working on it. All good and the car ran as expected.

I got home and washed the car as I think it was deserved after 8 months standstill.

now the PFC commander says “Connection Error” and the fans turn on. Car will turn but won’t start?

I have checked:
- ECU for loose connectors. Plugged and unplugged twice
- all connectors are bone dry
- battery voltage (12,5V)
- ECU print - does not look fried.
- all fuses look fine

What can be wrong? The car is giving me headaches and sleepless nights.

Mike

FDAUTO

iTrader: (4)

Likely the power fc died. Not uncommon. You'll need another one to verify

mluu92

also my first thought. Still hoping for a better diagnosis.
Don’t know anyone driving RX7 let alone PFC near me (located in Denmark).

FDAUTO

iTrader: (4)

Oh man... bigger problem, even if you got another power fc do you have a datalogit?

mluu92

nope, no datalogit either

j9fd3s

iTrader: (3)

do you have a stock ecu to try?

mluu92

Unfortunately not..

FDAUTO

iTrader: (4)

youre kind of stuck here. youre only real option is to buy another ecu. its extremely unlikely there is another problem causing what your issue. the most difficult part is the lack or resources to do anything. youre going to want to buy a datalogit or a more modern ecu if you want to continue your FD ownership. at a minimum there are some really good threads here on power fc usage and tuning that you could do for yourself what you cannot obtain locally.

mluu92

Yeah, also feels kinda stuck now.
was planning on upgrading to Haltech in the winter anyways but was hoping to drive the car for the rest of summer without issues.

If I were to source a datalogit it should be possible to see if the ECU is dead? The theory of dead ECU is still only qualified guessing I suppose.

FDAUTO

iTrader: (4)

a dead power fc will still allow the datalogit to connect in some cases. in other cases it will not. it really depends on how it failed internally whether or not it will allow for a connection. if the commander cant establish a connection with it then it will be likely the datalogit will not either

mluu92

It may be easier to find a stock ECU to verify the PFC is fried. But would the stock ECU even work
when I am running single turbo, rats nest delete, OMP delete etc. or does it have to be and
PFC?

j9fd3s

iTrader: (3)

stock ecu might not be happy, but it would work. you're just verifying that the ecu is the problem

mluu92

Exactly. It would only be with the purpose of ruling out other issues.
thanks! It should be easier to find a stock or PFC rather than PFC only

FDAUTO

iTrader: (4)

No rats nest, no omp, likely much larger injectors..... it won't even start. It will definitely crank but it won't start. If you had stock injectors MAYBE it would try and turn over but with different injectors the stock ecu is useless

mluu92

4x850cc injectors. Secondary are stock and stock secondaries in primary

FDAUTO

iTrader: (4)

with that, you have a chance of it starting. if it does, it will not be good. the stock ecu will be hit with so many errors and it will be in limp mode. i guess all you need is for it to fire off to confirm the suspicion. its worth a try

mluu92

Worth a shot! If anything I should be able to hear fuel pump running (which it does not do now) and my fans won’t be running. If that is the case I think It is safe to say the PFC is fried.

FDAUTO

iTrader: (4)

the non priming fuel pump is usually the biggest giveaway the ecu is dead

j9fd3s

iTrader: (3)

open it up, maybe it would be literally fried

mluu92

already did. Nothing to see

DaleClark

iTrader: (55)

First off I kind of doubt the PFC died. Really they are pretty hardy.

You need to do some troubleshooting as to what the engine is not getting that is causing the no-start. Fuel pump running? Ignition firing? Fuel injectors firing?

I would also look at whatever has changed between when it ran fine and now, whatever was touched is most likely the culprit.

Also probably worth doing a fuse check as well.

And dumb question - you spoke about washing the car. You didn't move the car out of the garage, shut it off when cold, wash it, now it won't start? Like you may have flooded it?

Dale

ptrhahn

iTrader: (9)

^^^^ Indeed.

If the power comes on and you can check sensors and such on the commander, it seems more like a relay, fuse, or exposed connection got wet when you washed it. I HAVE had a PowerFC go bad, but it didn't manifest like that.

mluu92

Already checked all of the above. And can’t check anything on the commander since it is dead (showing “Communication Error”).

I just sourced another PFC for testing and fuel pump primes and everything seems normal - which was not the case with my own.

I think it is safe to say my PFC is dead.

ptrhahn

iTrader: (9)

Yup, sounds like it.

mluu92

Was planning on going Haltech. Guess this is a gentle push in that direction