Ford vs Chevy Build-up

fordteacherguy · 05-02-2015, 09:38 AM

Rich,
These older Ford EFI systems didn't give live data so as Ford Tech we installed a "break out box) interface between the EEC processor and harness that had exposed pins where we could measure the pin voltages with a digital volt meter. You can do similar sensor checks with a thin paperclip and your voltmeter by slipping the clip along side the sensor wire in the sensors backshell until it hits the connector (back probing) and directly measure voltage coming from the sensor wire to ground and comparing to spec. Most 3 wire sensors have a wire that is 5V reference (orange) Sensor Ground (Black) and sensor output (green or some other color). I just probe and can identify signal wire (usually the one in the middle) that has the voltage between o and 5. Two wire sensors (IAT and ECT) jut tap into either ide and read voltage. Take readings with sensors hooked up.

Typical Values at idle and warm

TP around 1 volt
Baro 159 HZ +/-6 (Frequency, set meter on HZ)
ECT 1,3-..6 Warm
IAT 1.3 -.6 Warm
MAF 1V-? More with more air going through.

Make sure MAF wire is clean and doesn't have contaminants on it...maf is a major player with A/F.

Good luck!

fordteacherguy · 05-02-2015, 10:01 AM

Rich,

Looking at your photos, you don't have a vacuuum line hooked to baro do you? It looks like the same as a MAP sensor but baro's just read atmospheric pressure so the connection is open, no vacuum goes to that sensor.

Look like TP and IAT/ECT are working just curious of that Baro reading at -29.HG

FireSale · 05-02-2015, 11:46 AM

If that's barometric pressure as in weather, 29 hg is about right for Rich's area. Atlanta is 30 right now. The - could be a dash or a wiring glitch generating a negative value. EFI is a black box to me, so this is just a guess.

Dale

HandOverFist · 05-02-2015, 11:58 AM

Brian -

The only vacuum line I have hooked up on the car is the one you recommended to the fuel pressure regulator.

This sensor I replaced yesterday is the Map, correct?

The Baro is one I have not seen. Where in the engine bay/harness would it be located if in fact it is still present?

Edit : Ok, seems the sensor pictured above is actually a "BAP" sensor. I asked for a Map sensor at the parts store...any difference? At any rate this is the only sensor that resembles this in the engine compartment. Found this link for sensor locations... http://www.cjponyparts.com/tech-fox-body-engine/a/170/

Found this link also... http://sbftech.com/index.php?topic=19336.0

Fuel line fittings just arrived and I'm off to re-plumb the system as recommended. I also have a one wire alternator in hand so I can finally stop worrying with the thought of low voltage being a player in all of this.

black88coupe · 05-02-2015, 02:22 PM

The BAP/ MAP sensors are pretty much the same thing. On my factory speed density setup a vacuum line attaches to the sensor. When you are running factory Mass Air you would remove the vacuum line from the sensor and just leave the port open. I can't comment on how it is done with an aftermarket setup.

HandOverFist · 05-02-2015, 08:23 PM

Got it pretty much done today. The new Bap sensor shows no change on the screen of the controller...I may at a later date check voltage/Hz readings per Brian to see whats up with it.

I do have a 3-bar MAP sensor that came with the PMS. I think it was used in a blown application. Not sure if it could be used in my case...it would require a harness/connector that I do not have on hand.

Fuel system is now plumbed correctly. I have the regulator set at 36psi...will need to check what it does at WOT. For now the car starts easily and idles well with no loading up.

One wire alternator installed and working wonderfully.

Coolant catch can in place.

Pulled it out on the concrete pad out front to check the brakes/linelock. No hesitation at all when stalled to 2800rpm and stabbed WOT.

Buster, the useless guard dog.

Pinion angle set around 4 degrees. As far as I can tell it's ready for the track as soon as the front-end is aligned. Hope to have the car at Bowling Green next Saturday evening for a shakedown run.

Dave Noll · 05-03-2015, 01:56 AM

Just for reference, the BARO reading in this area (elevation 1050) is about 157Hz. Different area's will vary, higher elevation, lower Hz.

Earlier I wasn't really suggesting locking out the O2 sensors. I just wanted to know if that particular unit had the capability. @ full throttle the stock ECU ignores input from the O2's, uses pre-programmed values until throttle goes under about 80%.

Tony Corley · 05-03-2015, 06:16 AM

Car looks good Rich. It has been a great build to watch, you should be proud.
David, the Anderson Ford PMS he is running is a piggyback system that will allow the factory ecm to do as much or as little as you want. If I remember correctly, it can go into full standalone mode over 2000 rpm, if you want it too. They are a good, simple system to use.

05-02-2015, 09:38 AM	#1
fordteacherguy Member Join Date: Jun 2007 Location: Federal Way, WA Posts: 239 Likes: 38 Liked 160 Times in 51 Posts	Re: Ford vs Chevy Build-up Rich, These older Ford EFI systems didn't give live data so as Ford Tech we installed a "break out box) interface between the EEC processor and harness that had exposed pins where we could measure the pin voltages with a digital volt meter. You can do similar sensor checks with a thin paperclip and your voltmeter by slipping the clip along side the sensor wire in the sensors backshell until it hits the connector (back probing) and directly measure voltage coming from the sensor wire to ground and comparing to spec. Most 3 wire sensors have a wire that is 5V reference (orange) Sensor Ground (Black) and sensor output (green or some other color). I just probe and can identify signal wire (usually the one in the middle) that has the voltage between o and 5. Two wire sensors (IAT and ECT) jut tap into either ide and read voltage. Take readings with sensors hooked up. Typical Values at idle and warm TP around 1 volt Baro 159 HZ +/-6 (Frequency, set meter on HZ) ECT 1,3-..6 Warm IAT 1.3 -.6 Warm MAF 1V-? More with more air going through. Make sure MAF wire is clean and doesn't have contaminants on it...maf is a major player with A/F. Good luck! __________________ Brian Thompson NHRA Stock / Super Stock Class P/SA 6665 SS/MA 6665

05-02-2015, 10:01 AM	#2
fordteacherguy Member Join Date: Jun 2007 Location: Federal Way, WA Posts: 239 Likes: 38 Liked 160 Times in 51 Posts	Re: Ford vs Chevy Build-up Rich, Looking at your photos, you don't have a vacuuum line hooked to baro do you? It looks like the same as a MAP sensor but baro's just read atmospheric pressure so the connection is open, no vacuum goes to that sensor. Look like TP and IAT/ECT are working just curious of that Baro reading at -29.HG __________________ Brian Thompson NHRA Stock / Super Stock Class P/SA 6665 SS/MA 6665

05-02-2015, 11:46 AM	#3
FireSale VIP Member Join Date: Feb 2014 Location: Lakewood Washington Posts: 1,407 Likes: 29 Liked 237 Times in 126 Posts	Re: Ford vs Chevy Build-up If that's barometric pressure as in weather, 29 hg is about right for Rich's area. Atlanta is 30 right now. The - could be a dash or a wiring glitch generating a negative value. EFI is a black box to me, so this is just a guess. Dale __________________ Dale Shearon 68 Mustang 6394

05-02-2015, 11:58 AM	#4
HandOverFist VIP Member Join Date: Oct 2013 Location: Gulf Breeze, FL Posts: 1,651 Likes: 8 Liked 33 Times in 16 Posts	Re: Ford vs Chevy Build-up Brian - The only vacuum line I have hooked up on the car is the one you recommended to the fuel pressure regulator. This sensor I replaced yesterday is the Map, correct? The Baro is one I have not seen. Where in the engine bay/harness would it be located if in fact it is still present? Edit : Ok, seems the sensor pictured above is actually a "BAP" sensor. I asked for a Map sensor at the parts store...any difference? At any rate this is the only sensor that resembles this in the engine compartment. Found this link for sensor locations... http://www.cjponyparts.com/tech-fox-body-engine/a/170/ Found this link also... http://sbftech.com/index.php?topic=19336.0 Fuel line fittings just arrived and I'm off to re-plumb the system as recommended. I also have a one wire alternator in hand so I can finally stop worrying with the thought of low voltage being a player in all of this. __________________ Rich Taylor I/SA - 321 Last edited by HandOverFist; 05-02-2015 at 12:40 PM.

05-02-2015, 02:22 PM	#5
black88coupe Member Join Date: Jan 2008 Posts: 352 Likes: 18 Liked 19 Times in 12 Posts	Re: Ford vs Chevy Build-up The BAP/ MAP sensors are pretty much the same thing. On my factory speed density setup a vacuum line attaches to the sensor. When you are running factory Mass Air you would remove the vacuum line from the sensor and just leave the port open. I can't comment on how it is done with an aftermarket setup. __________________ Mitch Beri- The Motor City 1985 GT- “Stock-ish” 5.0 motor, AOD/ trans brake. 12.68 @ 101.31mph. https://www.facebook.com/groups/FOXBODYFLEAMARKET/

05-02-2015, 08:23 PM	#6
HandOverFist VIP Member Join Date: Oct 2013 Location: Gulf Breeze, FL Posts: 1,651 Likes: 8 Liked 33 Times in 16 Posts	Re: Ford vs Chevy Build-up Got it pretty much done today. The new Bap sensor shows no change on the screen of the controller...I may at a later date check voltage/Hz readings per Brian to see whats up with it. I do have a 3-bar MAP sensor that came with the PMS. I think it was used in a blown application. Not sure if it could be used in my case...it would require a harness/connector that I do not have on hand. Fuel system is now plumbed correctly. I have the regulator set at 36psi...will need to check what it does at WOT. For now the car starts easily and idles well with no loading up. One wire alternator installed and working wonderfully. Coolant catch can in place. Pulled it out on the concrete pad out front to check the brakes/linelock. No hesitation at all when stalled to 2800rpm and stabbed WOT. Buster, the useless guard dog. Pinion angle set around 4 degrees. As far as I can tell it's ready for the track as soon as the front-end is aligned. Hope to have the car at Bowling Green next Saturday evening for a shakedown run. __________________ Rich Taylor I/SA - 321

05-03-2015, 01:56 AM	#7
Dave Noll Senior Member Join Date: Nov 2007 Location: Div. 6, Eastern, WA Posts: 712 Likes: 2,716 Liked 240 Times in 112 Posts	Re: Ford vs Chevy Build-up Just for reference, the BARO reading in this area (elevation 1050) is about 157Hz. Different area's will vary, higher elevation, lower Hz. Earlier I wasn't really suggesting locking out the O2 sensors. I just wanted to know if that particular unit had the capability. @ full throttle the stock ECU ignores input from the O2's, uses pre-programmed values until throttle goes under about 80%. __________________ Dave Noll, EF/S ,?/SA 6526

05-03-2015, 06:16 AM	#8
Tony Corley Member Join Date: Nov 2011 Posts: 264 Likes: 42 Liked 61 Times in 25 Posts	Re: Ford vs Chevy Build-up Car looks good Rich. It has been a great build to watch, you should be proud. David, the Anderson Ford PMS he is running is a piggyback system that will allow the factory ecm to do as much or as little as you want. If I remember correctly, it can go into full standalone mode over 2000 rpm, if you want it too. They are a good, simple system to use.