I just installed my PowerFC + Commander and now my car woln't start. I double and tripple checked the wires I cut and I'm sure they are the correct ones.

The car turns over and starts to start, but then just dies.

My commander turns on and I can monitor anything... what can I look for!? what do I do?!!?!?

BAH... I thought you just plug this thing in and let the car idle. Too bad mine woln't idle

Any help would be appreicated!
Thanks in advance!
Chris

 

Just a little more info... when I turn the key to the ON position I hear fast clicking from under the hood... perhapes the fuel pump? (but why would the sound be comming from under the hood?)

 

The fuel pump does not make a clicking sound plus it is in the gas tank not under the hood.

Reinstall your stock ECU along with the wires cut, and try starting the car. You need to isolate the problem as PFC or something else first. Then go from there.

 

I wanted to try that last night but I wasn't sure if installing the stock ECU w/ wires cut would hurt it or not. I guess when I get home I'll try that. Thanks.. if that works fine does that mean my PFC is bad? or is it possible that it has somthing other than base maps on it? I got the PFC from www.phase2motortrend.com.

 

1) wire the wires back together - for now - maybe wire them up to a 4-wire connector.

2) see if that helps. The PCF should run with the wires in place, it just happens to not do such a good job determining what electrical load there is, so you might idle a few 100 rpm higher than you would otherwise.

3) go back to your stock ECU. Does it run? If not then something bad may have happened and you will need to fix it. If it works put the PFC back in (with the wires connected)

4) If the PFC still fails, then something is probably wrong with the unit....

that's my $.02
-Erik

 

Those are good sugestions. The diagram is kind of backwards and I think if you cut the wrong wires your car won't start.

 

Reconnected the 4 wires and it still wouldn't start... not even w/ the stock ECU but I think I know why.

https://www.rx7club.com/vforums/show...threadid=33021

I posted that on the 3rd gen board because it gets more hits and this isn't exactly PFC specific anyomre

Thanks for all the assistance... and if you have anymore ideas.. I'm open!

 

Let's get this straight. It was running before. You cut the 4 wires and plugged in the PFC and then it wouldn't start? Then you hooked the wires back up and it still wouldn't start? Then you plugged in the old ecu and still won't start?
If it was running before, and now everything is back the way it was, this does not make sense.
My memory is coming back to me on the 4 wires. I think if you cut the wrong wires, like if you read the diagram backwards, some of them are for the oil metering pump. Maybe it ran for a little while?
Are you sure the PFC and the wires are the only thing that were changed? If the PFC was screwed up then maybe the car is flooded now. Once that happens it can be a bear to start even after everything else is fixed.
Why didn't you get the PFC from Jason? Hard to believe you found a better price...

 

OK.... I got the PFC from phase2motortrend on a group buy $1050 for PFC and commander. This was after Jasons group buy so it turned out to be a better price. All 4 wires WERE the correct wires... I have checked them w/ the wiring diagram and aginst several photos of others cars done. All 4 wires are reconnected and the stock ECU is back in the car. The car runs.... I can step on the gas lightly and run it up as high as I want no problems... BUT if I slam on the gas or anything that causes the boost to kick in it will try and die. The Check engine lights on and the code is for the Boost Pressure Sensor. I spent 2 hours this morning testing EVERY connection in the ECU wiring harnes and not a one is crossed and all of them are fine. I then opened up the Stock ECU and tested to make sure there is continuity between the prongs INSIDE the ECU and the back of the wiring plug, all is ok there. Then I tested what the ECU is sending to the Pressure sensor and that is OK. Sooo.... techinically the ONLY thing left is to get a vacuum pump and conntect it to the Pressure sensor and make sure it's sending the correct voltages back to the ECU. I have a feeling that either the boost pressure sensor just went out... or the PFC poped the boost pressure sensor. I found my auto parts store will let me rent a vacuum pump for $40 and I get it all back when I return it. If this is the problem then I guess it's time to find someone w/ a pressure sensor they can sell me and install that to make sure everything works again. Then try the PFC again... if it pops again then I know its the PFC otherwise it was just time for the sensor to go... *shrug*

 

Forget it... I'm stumped! Just went out and bought a vacuum pump and hand pumped the sensor and the voltage comming out was adjusting... so I'm guessing the sensor is correct. Maybe it IS the wiring harness. BAH! Where to next.............

 

To test the map sensor, you need to apply pressure, not vacuum.

I use a hand bicycle air pump. Connect it through a one way valve to a "T" connector. You can use a cheap aquarium valve. From the "T", run a hose to your boost gauge and the other to the map sensor. As you apply pressure, you can read the voltage on the commander and read pressure on the boost gauge. This then can be checked against what the RX-7 manual. If you have a high impedance volt meter, you can also check the voltage right at the map sensor.

 

Not the map sensor... the boost pressure sensor (Page F-181 in the workshop manual).

 

Posible reason for not originally starting with PFC. On page 32 of the manual you will see the cranking fuel injection correction menu. You go to the water temperature menu first then go right from it to get to this menu. When I "test" set the values today to the values listed on the page, my engine did not start . Returning them as they were, the engine started right up.

Those of us here in Houston who have PFC from Ray, have more fuel added in. Here are my values.

+80C:12.0
+50C:17.3
+30C:32.0
+10C:59.0
-10C:87.2
-30C:104.2

 

I reinstalled the PFC (w/ the 4 wires disconnected just for the heck of it and my settings matched what you have there. I'm really starting to think that 1 of 2 things happened. Either the wiring harness is messed up or the PFC messed somthing else up.

BTW the fast click sound is comming from under the intake manifold where it connects to the pipe going out to the intercooler. If I put my hand right there I can feel the clicking also! But thats w/ the PFC installed so if the wiring harness is messed up that could be causing that I guess.... BAH.. time to search for a wiring harnes.

 

Talking about wiring harness's. I replace both the main engine and ignition harness's when I rebuilt my engine this spring.
Besides the few broken connectors due to heat, I noticed that many wires had high internal oxidation. Most of the copper wire is not tinned and the insulation has poor moisture/O2 protection.
My O2 sensor connector was bad due to oxidation of the copper wire at the connector , and that connector is definitely in a dry warm area.

I had always had an ignition problem where it would start misfiring around 6800 rpm as soon as boost went over about 11PSI. I installed a Crane HI-6R but this did not solve the problem. Then I disconnected the ignition harness from the chassis harness and ran it directly to the Crane and ignitor.
This did not help either. When I installed the new ignition harness this year the problem was fixed. By the way, this new harness does not have shielding on it


wiring harness, engine, ignition coils, N3A3-18-05Z(3),$78

wiring harness, engine, ECU & trans, N3A1-18-05ZF/G,$825

 

Chuck,

Are those the prices you paid, or are they list? I am planning on putting new wires in with my rebuild in the future. What did you use for insulation/wire wrapping? I was considering using the thermal wrap type but I am worried about the moisture. What about a dual wrap, electrical tape and then thermal type?

Thanks.

 

Those were Houston dealer prices with tax. Mazadtrix does not sell them. The only place I used thermo wrap was were the cable passes over the DP along the firewall. Since my engine is non-seq it now gets more air flow around and through the engine.