Power FC Pro...Help....My car won't start...No sound of fuel pump pressure

[Kriskouki]

Hi,

I am new to Power FC.....

I got an Power FC Pro, which the label states that "PFC SR201 XXXX-XXXX", which after I looked it up, it's matching with my current ECU, which is the "red WC" (Zenki s14 sr20det)

Today, I plugged in my Power FC. The commander gets powered fine and I can play with all the functions on the Power FC, but once I tried to crank my car, it will not turn over......Then, I went back to read all the Power FC faqs that many people write about and did all the things that are recommended such as turning off the boost control kits, resetting the ECU and such....Again, the car won't start.....And, when I put my stock ECU back, everything fires right up.......

However, with Power FC installed, I noticed that I didn't hear the sound of the fuel pump pressure when I turn the iginition key to "ON" like I usually do with my stock ECU......So, I am asking you guys to see that is it normal or not......

Please help and suggestions are more than welcome.........

[Mikester]

IIRC, there is a "power" signal and a "backup power" signal going into the main harness connector at the PFC. PFC needs power to both in order to function; standard ECU does not, so you will never know the problem is there until you try to install a PFC. You should definitely check the pinouts for your car to verify... but I am fairly sure what I'm telling you is correct.

[Taylor008]

You sure your other ECU plug is plugged in? The one that goes up by the glove box.

I don't know how power FC's work, but fuel pump wire and starter signal wire go through that smaller white/brown plug. Car should crank even if it doesn't have an ECU plugged in.

[Kriskouki]

IIRC, there is a "power" signal and a "backup power" signal going into the main harness connector at the PFC. PFC needs power to both in order to function; standard ECU does not, so you will never know the problem is there until you try to install a PFC. You should definitely check the pinouts for your car to verify... but I am fairly sure what I'm telling you is correct.

i'll check that out, but I am quite sure that the wiring is completed as i did the work myself......

Anyways, please tell me that once you first install power fc when you turn the igition switch to 'ON' position, did you hear the fuel pump working? (did your fuel pump relay working).....i didn't hear it when power fC plugged in......is this normal?.......i am positively sure that the engine doesn't fire up because the fuel pump isn't pumping the gas but as i am new to power FC so i need to ask someone who has worked with it before

[e1_griego]

No, it's not normal. He's telling you to check the wiring b/c it should kick the pump on.

[Kriskouki]

No, it's not normal. He's telling you to check the wiring b/c it should kick the pump on.

is it true?.....Well, the power Fc I have is the same model as my stock ecu....and all the function is working through the handheld commander....but the only problem now is the car won't start.....

[Kriskouki]

Updates:

I double-checked all the power wires (+12V) and ground wire (0 V) of my ECU and everything is correct.....The ECU backup power also maintains at +12V after I turned off the key....So, I am pretty sure that wiring is correct......

Do you have any other ideas?....

What I noticed is that when the car was cracking, it looks like the Power FC is restarting.....Do you have the same thing?

[steve shadows]

Sounds like your wiring harness is not plugged in tightly or all the way into the power FC female receiving end of the harness. OR Your wiring harness is shredded and falling apart just above the EMS/ECU blue plug and there is something major loose or with a shotty connection.

[EvoVIII808]

ECCS relay.

Blue relay in passenger side fuse box.

You can swap it with any of the blue relays just to see if it is bad.
I had this same problem with my SR swap and the ECCS relay was no good. I put the AC relay in its spot and it has been working every since.

[Kriskouki]

Sounds like your wiring harness is not plugged in tightly or all the way into the power FC female receiving end of the harness.
http://www.booksstore.info/11k/bass.jpg
http://www.booksstore.info/jokelist/boa.jpg

Everything was plugged in all the way......

I popped up the Power FC box to inspect all the circuit and everything looks good...no smell...no burnt...no surprises.......

I even measured the voltage across pin 18, which is the fuel pump relay on the power FC, it turned out that when I turned the ignition to ON position, it always has a constant +12V. However, the result is different when I plugged in to stock ECU.....The stock ECU would send a ground signal (0Volt) to the fuel pump relay to prime for about a second and after that it sends (+12v) to disable the fuel pump relay........

Furthermore, I am sure that my fuel pump relay is working perfectly as I always hear a click sound when I turned my ignition to ON position with stock ECU......And, I am so sure that the ECCS relay is working as I have measured all the supply and ground following by the pins diagram and everything is perfect.......

Anybody has other ideas?......

Now, I am prone to think that it might be the software inside the Power FC itself, but I have no other tools to check unless I have a datalogic.....

[EvoVIII808]

yeah this is weird, ill check pin 18 and see what mine does once i get off work.

[fliprayzin240sx]

I just went thru this crap, make sure the ECCS relay is turning on. My relay was faulty and wasnt passing full 12v into the PFC. You need to bust out a multimeter and check to see if you're getting voltage into the switched 12v pins into the PFC, with the key on.

[Jake1992]

I had kind of the same problem.. i had this in a thread a while back it was my eccs relay.. and would turn the car on on stock ecu swap ecu's to the power fc and it would prime ... i remember hearing my fuel pump though, but wouldnt hear the click of the relay( bought the car from the previous owner which stated the power fc was off tune it would not start, he brought it to many places and people which told him the ecu was fried, he sold it to me like that telling me it was not tuned right :S ) after some measuring by the relays i got the problem it was wired wrong, my battery's would drain in 3 days , there was a positive lead coming in that the ecu would stay on....

measuring those relays and sorting that out might be your problem check all grounds too , power fc ecu's are very sensitive and not getting full 12v they start tripping

[Kriskouki]

I just went thru this crap, make sure the ECCS relay is turning on. My relay was faulty and wasnt passing full 12v into the PFC. You need to bust out a multimeter and check to see if you're getting voltage into the switched 12v pins into the PFC, with the key on.

I had kind of the same problem.. i had this in a thread a while back it was my eccs relay.. and would turn the car on on stock ecu swap ecu's to the power fc and it would prime ... i remember hearing my fuel pump though, but wouldnt hear the click of the relay( bought the car from the previous owner which stated the power fc was off tune it would not start, he brought it to many places and people which told him the ecu was fried, he sold it to me like that telling me it was not tuned right :S ) after some measuring by the relays i got the problem it was wired wrong, my battery's would drain in 3 days , there was a positive lead coming in that the ecu would stay on....

measuring those relays and sorting that out might be your problem check all grounds too , power fc ecu's are very sensitive and not getting full 12v they start tripping

can you guys please help confirm back to me..." Even on the bad ECCS relay, do you still hear your fuel pump prime with Power FC?".....If the answer is yes, then...I am going to replace the ECCS relay to see the difference......

[Jake1992]

can you guys please help confirm back to me..." Even on the bad ECCS relay, do you still hear your fuel pump prime with Power FC?".....If the answer is yes, then...I am going to replace the ECCS relay to see the difference......

Yes mine was ... it would turnover too smell like gasoline in the whole house but wouldnt start... Man i went nuts .. did everything i gave it up , then after a month or so i was looking at the power fc on a saturday and i decided to do it again... even passed new wire from ignition (key) to the ecu... that was keeping the ecu on :S

[fliprayzin240sx]

Well, whats weird with mine was it works fine with the stock ECU. Moment I plugged in my PFC and try to turn it on, my fuel pump relay starts clicking and pump wont prime. Thought maybe it was a bad fuel pump relay, swapped it with a known good one, same crap.

Read my adventures here: http://zilvia.net/f/engine-tech/500050-s14-fuel-pump-relay-buzzing.html

[Kriskouki]

Yes mine was ... it would turnover too smell like gasoline in the whole house but wouldnt start... Man i went nuts .. did everything i gave it up , then after a month or so i was looking at the power fc on a saturday and i decided to do it again... even passed new wire from ignition (key) to the ecu... that was keeping the ecu on :S

Well, whats weird with mine was it works fine with the stock ECU. Moment I plugged in my PFC and try to turn it on, my fuel pump relay starts clicking and pump wont prime. Thought maybe it was a bad fuel pump relay, swapped it with a known good one, same crap.

Read my adventures here: http://zilvia.net/f/engine-tech/500050-s14-fuel-pump-relay-buzzing.html

I am going to replace both fuel pump relay and ECCS relay as soon as I have time......

[EvoVIII808]

anyupdate??

[Kriskouki]

anyupdate??

Not at this moment...but everything will be answered very soon as I just got another Power FC which has the same part number....And, this one fired right up on the other car.....So, we will get the answer very soon......

[EvoVIII808]

ECU problem...damn that sucks!

[Kriskouki]

ECU problem...damn that sucks!
Still not get the conclusion yet.....I have been busy with my jobs.....Still need to wait guys....

[Kriskouki]

Still not get the conclusion yet.....I have been busy with my jobs.....Still need to wait guys....

Problem solved.....I plugged the power FC on my friend's car and it fires right up......Already shot a video to show it to you......will post the link a little later

So, it is confirmed that the wiring on my car is not 100% completed...not a Power FC's problem.....

[Maverick06xx]

Problem solved.....I plugged the power FC on my friend's car and it fires right up......Already shot a video to show it to you......will post the link a little later

So, it is confirmed that the wiring on my car is not 100% completed...not a Power FC's problem.....

Hey im having the same problem, did you ever find what the problem was?