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The voltage at my battery with the ignition on is a steady 12.2v. On the laptop it’s not steady at all it bounces anywhere from 10v-11.85v. It tends to be in the mid 11v range but like I said it’s not steady it just bounces all over the place. Once I turn the ignition off I see the voltage goes up to somewhere in the low 12v but still not steady.
I tried installing a fairly newer battery from one of my other cars and still had the same problem. I think I might have wiring issues, it’s just weird that sometimes it works and sometimes it doesn’t. Where does the pro-m gets its voltage reading from? I can start by checking there.

I was reading on a website that Ford ecm need to see 18v to be able to do any programming, I wonder if the pro-m is set up the same way.
That's not good. The voltage reading in the Pro M software should be steady and match or be ever so slightly lower than the voltage measured directly at the battery.

The Pro M EFI harness has a relay for ECU power in the kickpanel. I'd start by looking at that. Make sure the wires are securely in there. It's possible that one came loose when pulling everything through the firewall.
 

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I'm considering this system. Would paying the $150 fee to have Pro-m enter vehicle specifics allow you to bypass this mess?
 

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Discussion Starter #23
That's not good. The voltage reading in the Pro M software should be steady and match or be ever so slightly lower than the voltage measured directly at the battery.

The Pro M EFI harness has a relay for ECU power in the kickpanel. I'd start by looking at that. Make sure the wires are securely in there. It's possible that one came loose when pulling everything through the firewall.
I checked that relay I believe it says ECU & sensors. I had slightly lower than battery voltage there but it was steady. I’m considering disconnecting the sensors one by one and see if I possibly have a shorted out sensor. I will recheck everything again and write notes so I can remember exactly what voltages I’m getting at every spot. I might have to get a hold of Chris cuz I’m at a lost here.
 

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I'm considering this system. Would paying the $150 fee to have Pro-m enter vehicle specifics allow you to bypass this mess?
Partially, but it really depends on what you're calling the "mess." The $150 would get all the injector data entered for you, so there wouldn't be the issue with the battery voltage offsets having been entered incorrectly. The $150 would have done nothing to prevent the high fueling corrections that almost certainly result, at least partly, from the dipstick being out. Any leak of air into the crankcase with a PCV system results in unmetered air entering the combustion chambers and a lean condition. The beauty of this system is that we very easily saw that the system is adding 20% fuel when it shouldn't have had to, so something must have been wrong. The $150 would not prevent this voltage issue. I'm suspicious of a loose connection, but that remains to be proven.
 

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Discussion Starter #25
I'm considering this system. Would paying the $150 fee to have Pro-m enter vehicle specifics allow you to bypass this mess?
No. For the $150 you will get basic info entered into the calibration. You still have to do the basic start up procedures. TPS, Base timing, fuel pressure, idle speed and injector slopes. Its not hard to do if you read the write up and your car is in good running condition. I thought mine was cuz it was running what I considered fine with the stock computer but now that I have this system and I can see everything on the laptop and now see I car has issues.
 

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I checked that relay I believe it says ECU & sensors. I had slightly lower than battery voltage there but it was steady. I’m considering disconnecting the sensors one by one and see if I possibly have a shorted out sensor. I will recheck everything again and write notes so I can remember exactly what voltages I’m getting at every spot. I might have to get a hold of Chris cuz I’m at a lost here.
I think you should talk to Chris. He deals with the harnesses everyday. I haven't directly looked at one for several weeks, and that was only to add boost control wiring. I didn't look at relays. But... if memory serves me correctly, the the one labeled ECU and Sensors is the main power one. Mine is labeled PCM PWR, but I have the first 96-98 prototype so it has some minor differences. You want to make sure the wires in there are all tight. Did you check voltage on the side of the relay heading to the ECU with the key in the ON position?
 

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Discussion Starter #27
I think you should talk to Chris. He deals with the harnesses everyday. I haven't directly looked at one for several weeks, and that was only to add boost control wiring. I didn't look at relays. But... if memory serves me correctly, the the one labeled ECU and Sensors is the main power one. Mine is labeled PCM PWR, but I have the first 96-98 prototype so it has some minor differences. You want to make sure the wires in there are all tight. Did you check voltage on the side of the relay heading to the ECU with the key in the ON position?
I just checked. Ignition off I’m at 12.47v at bettery post and 12.2v at ECM & Sensors relay (only ECM relay in this harness). Once I turn the ignition on it dropped to 12.2v at battery post and 12.02v at relay. I checked power coming out of relay and the wire coming out of the relay and there isn’t any voltage drop there. However the power that switches the relay on and off is at 11.9v. All voltages are steady but the voltage reading on the laptop is all over the place anywhere from 10-11.8v.
 

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I just checked. Ignition off I’m at 12.47v at bettery post and 12.2v at ECM & Sensors relay (only ECM relay in this harness). Once I turn the ignition on it dropped to 12.2v at battery post and 12.02v at relay. I checked power coming out of relay and the wire coming out of the relay and there isn’t any voltage drop there. However the power that switches the relay on and off is at 11.9v. All voltages are steady but the voltage reading on the laptop is all over the place anywhere from 10-11.8v.
I'd be looking at the power wires in the main connectors to the ECU next then. I'd have to look up which ones they are and can't right now. You're best bet on this is to give Chris a call in the morning.
 

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Discussion Starter #29
I'd be looking at the power wires in the main connectors to the ECU next then. I'd have to look up which ones they are and can't right now. You're best be on this is to give Chris a call in the morning.
Yea that was my next go to but I don’t know which one connector has the main power wire. last night I was trying to wiggle the wires around at the connectors while watching the laptop to see if I saw any change but had no luck.
 

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Any chance that this is an alternator issue?
I don't think so. I think you'd see low voltage when reading at the battery which isn't happening here.

Aside from the power into the ECU, bad grounds could also be causing an issue. Make sure you have grounded everything exactly as described in the instructions.
 

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Discussion Starter #32
I checked alternator voltage while car was running and it’s at 14.4v. I also tried wiggling the wires at the alternator connector while watching the laptop and still no change.
 

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Discussion Starter #33
John do you know where the ECM gets its voltage reading from?

When I installed the supplemental harness I had to solder some wires, I’m going to try and go back and check make sure they didn’t come apart. I know I’m far from good at soldering. As far as ground there was only 1 ground cable going directly to the battery terminal and that was it, no power wires.
 

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i would go right to the pro m connections that are directly connected to the battery terminals. but i think you would have a lost communication code as well.
 

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No. For the $150 you will get basic info entered into the calibration. You still have to do the basic start up procedures. TPS, Base timing, fuel pressure, idle speed and injector slopes. Its not hard to do if you read the write up and your car is in good running condition. I thought mine was cuz it was running what I considered fine with the stock computer but now that I have this system and I can see everything on the laptop and now see I car has issues.
I just had to do the whole thing over because i screwed with my laptop and lost everything. Wasn't hard to do. Im lucky I kept the hard copy of the maf transfer function.
 

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John do you know where the ECM gets its voltage reading from?

When I installed the supplemental harness I had to solder some wires, I’m going to try and go back and check make sure they didn’t come apart. I know I’m far from good at soldering. As far as ground there was only 1 ground cable going directly to the battery terminal and that was it, no power wires.
So the supplemental harness is in play, and you didn't have these problems before its installation? That's good information. If that's the case, the big red flags for me are going to be the new connections related to power. One is the area where the red wire in the supplemental gets spliced in with the red wire on pin 87 of the power relay. The other is going to be the area where the supplemental's black wire gets spliced into the main ground wire that connects to battery negative.

You've got me thinking about battery voltage in general now. If you voltage is dropping way down, that's going to put you into lower regions of the injector battery voltage offset table, which was messed up. I am more hopeful that ever that once this voltage issue is resolved and the correct offset table is uploaded, you are going to be in much better shape.
 

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Discussion Starter #37
I will check the ground connection at the battery terminal, I used one of those crimp connectors but can’t remember if I also solder it there as well.

I can’t answer that question, I bought the system second hand and then purchased the supplemental harness and wired it in. Then I installed them both together, I never ran the system with the old software. According to previous owner it was working just fine, and like I said it was working fine for me to until 2 weekends ago when I started getting that error. I let the car sit throughout the week since I was working and then this past Friday I made a couple of changes and worked fine at first, later that same day I went back to change the voltage offset to what you recommended and it started doing it again. I will check the soldered connections and report back tonight.
 

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FYI,
Made a log for "PCM power" at idle.
The first graph is at startup.
The second graph, coolant temps are approx. 203 degrees F or 95.1 degrees C.
And the last graph is with the cooling fan #1 is "ON" at 205.4 degrees or 96.4 degrees C.

This log was taken at idle and as you can see voltages will move around some but not the huge differentials you're getting from 14.5 vdc.

Startup
1060524



Second graph, coolant temps are approx. 203 degrees F or 95.1 degrees C
1060525



Last graph is with the cooling fan #1 is "ON" at 205.4 degrees or 96.4 degrees C
1060523


I hope this helps for a comparison at idle.
Michael Plummer
 

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Discussion Starter #40
FYI,
Made a log for "PCM power" at idle.
The first graph is at startup.
The second graph, coolant temps are approx. 203 degrees F or 95.1 degrees C.
And the last graph is with the cooling fan #1 is "ON" at 205.4 degrees or 96.4 degrees C.

This log was taken at idle and as you can see voltages will move around some but not the huge differentials you're getting from 14.5 vdc.

Startup
View attachment 1060524


Second graph, coolant temps are approx. 203 degrees F or 95.1 degrees C
View attachment 1060525


Last graph is with the cooling fan #1 is "ON" at 205.4 degrees or 96.4 degrees C
View attachment 1060523

I hope this helps for a comparison at idle.
Michael Plummer
Michael I see your voltage also fluctuates but stays in the mid 14v range. On mine the alternator puts out 14.4v while running but on the laptop I never see nothing more than mid 13v. It’s like I’m loosing 1v somewhere in the system.

I been wanting to check the soldering connection where the supplemental and main harness main power join but for I’ve been really busy with this kitchen remodel.

And now I have another problem, for the past 2 days I haven’t been able to find my car keys lol. I think my kids might have gotten a hold of them.
 
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