View Full Version : Map sensor help
Roland Jacques
10-04-2008, 03:08 PM
As im trying to hook up my EFIE. I am not getting the fluctuating voltage of 1-1.5 volts that the directions say I should be seeing.
Could my MAP be bad?
2001 GMC Savanna van.
What I think is the MAP sensor is has three wires.
Orange: no voltage (this is the one I think is suppose to be reading 1-1.5 volts)
Green: no voltage
Grey: 5.8-6.2 volts
The orange one is the one I thought should have fluctuating voltage of 1-1.5 volts
H2OPWR
10-04-2008, 03:17 PM
I am not sure what make or model of vehicle you have and I am sure they are all different. My Jeep Wrangler's MAP sensor voltage fluctuates from 7 volts down to 1 volt. My wires are 12 volt positive lead, netegative leat and the variable voltage signal lead to the ECM.
precaster1@msn.com
10-04-2008, 04:18 PM
Orange is the right one, i think your map is bad.
Roland Jacques
10-04-2008, 05:03 PM
Thanks, guys. I was thiking it should be the Orange one also.
I guess i'll go get a new sensor. The Bad Map sensor might explane my 10.5 MPG on that Boxvan, my other GM boxvan got 12 mpg.
mytoyotasucks
10-04-2008, 07:40 PM
As im trying to hook up my EFIE. I am not getting the fluctuating voltage of 1-1.5 volts that the directions say I should be seeing.
Could my MAP be bad?
2001 GMC Savanna van.
What I think is the MAP sensor is has three wires.
Orange: no voltage (this is the one I think is suppose to be reading 1-1.5 volts)
Green: no voltage
Grey: 5.8-6.2 volts
The orange one is the one I thought should have fluctuating voltage of 1-1.5 volts
the Efie hooks up to ur O2 sensor, not the map.
Roland Jacques
10-04-2008, 08:54 PM
Actually my EFIE hooks up to both MAP & 02 sensor.
on a side note. I got to say im a little confused as to how some folks use standard MAP EFIEs, on there O2 sensor. According to what ive read & and the direction with my EFIE.
To enhance the O2 sensor you need to raise the voltage to lean out.
To enhance the MAP sensor you need to lower the voltage.
FWIW Turns out the green wire on my GMC's MAP sensor was the signal wire.
Roland Jacques
10-04-2008, 10:18 PM
I just need some clarification. I thought a Map enhancer was also an EFIE.
Is an EFIE strictly for the O2 sensors?
And a MAP enhancer is not an EFIE?
Boltazar
10-04-2008, 10:44 PM
Is an EFIE strictly for the O2 sensors?
And a MAP enhancer is not an EFIE
That's the way I see it.
mytoyotasucks
10-04-2008, 11:02 PM
description of the EFIE (Electronic Fuel Injection Enhancer)
precaster1@msn.com
10-04-2008, 11:28 PM
Actually my EFIE hooks up to both MAP & 02 sensor.
on a side note. I got to say im a little confused as to how some folks use standard MAP EFIEs, on there O2 sensor. According to what ive read & and the direction with my EFIE.
To enhance the O2 sensor you need to raise the voltage to lean out.
To enhance the MAP sensor you need to lower the voltage.
FWIW Turns out the green wire on my GMC's MAP sensor was the signal wire.
Are you sure? All 3 rigs of mine its been the orange, I thought it was green once but it made the engine act really weird when hooked up. But with no voltage you still have something wrong with the map.
Boltazar
10-04-2008, 11:33 PM
when using a MAF enhancer device to control gas flow amount should the HHO inlet into the engine be placed before or after the MAF sensor
Actually my EFIE hooks up to both MAP & 02 sensor.
on a side note. I got to say im a little confused as to how some folks use standard MAP EFIEs, on there O2 sensor. According to what ive read & and the direction with my EFIE.
To enhance the O2 sensor you need to raise the voltage to lean out.
To enhance the MAP sensor you need to lower the voltage.
FWIW Turns out the green wire on my GMC's MAP sensor was the signal wire.
Curious,does the enhancer you purchased control both o2 and map sensors in one unit.And if so where did you find it?
scrode
10-05-2008, 01:38 PM
when using a MAF enhancer device to control gas flow amount should the HHO inlet into the engine be placed before or after the MAF sensor
I don't think it would matter, seeing with the enhancer you've made the sensor null. But, having said that I would put it after, just because (my random thinking only:eek:) I would think you have a truer vacuum after all the BS on the intake. It seemed to help on my car.:rolleyes: or I just think it did;)
Roland Jacques
10-06-2008, 11:53 AM
Are you sure? All 3 rigs of mine its been the orange, I thought it was green once but it made the engine act really weird when hooked up. But with no voltage you still have something wrong with the map.
Yeah, my sensor was even marked next to each wire. showing green was for sensor, i thought it was weird also.
Roland Jacques
10-06-2008, 12:00 PM
Curious,does the enhancer you purchased control both o2 and map sensors in one unit.And if so where did you find it?
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&sspagename=STRK%3AMEWAX%3AIT&viewitem=&item=110290283824
It it works good seems to be built well and the price is right.
In hind sight i rather have one with built in volt meters but im sure tat wood cost a bit more $$$
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&sspagename=STRK%3AMEWAX%3AIT&viewitem=&item=110290283824
It it works good seems to be built well and the price is right.
In hind sight i rather have one with built in volt meters but im sure tat wood cost a bit more $$$
Yeah that's not a bad price for both map and o2.Do your instructions say how to install it if you have 2 o2s?Just curious how they wire it.
Roland Jacques
10-06-2008, 02:16 PM
Yeah that's not a bad price for both map and o2.Do your instructions say how to install it if you have 2 o2s?Just curious how they wire it.
It only reads 1 O2 sensor, then enhances it, and sends out 2 signal to the ECU. so its thinks it reading from 2 O2 sensors,
Right now im not sure i even needed the Map part.
I no I leaned out my van too much yesterday. Funny thing is I only noticed hesitations when the van shifted to third gear, but no hesitations any other time.
Time to hook up the HOD and see how this works.
It only reads 1 O2 sensor, then enhances it, and sends out 2 signal to the ECU. so its thinks it reading from 2 O2 sensors,
Right now im not sure i even needed the Map part.
I no I leaned out my van too much yesterday. Funny thing is I only noticed hesitations when the van shifted to third gear, but no hesitations any other time.
Time to hook up the HOD and see how this works.
If you overlean with a map en. you will also notice some chugging when slowly accelerating when cruising at high speeds.Most instructions say to increase until the motor stumbles then back off slightly,which I've found is way too much and will cause poor performance and most likely you'll use more fuel than without it.I've found that setting the map en. low then finish tuning with the o2 efie works well.Tuning goes smoother if you tune a little then drive for a day or so then tune a little and so forth.This way the ecm is not as likely to catch on to what you're up to.
Good luck and thanks for the efie info
Roland Jacques
10-08-2008, 10:07 AM
Thanks for the tips
I’m taking a step back with enhancing. I’m just trying to understand what im doing a little better. So For now, Im trying not to do any leaning of fuel and I turned the MAP enhancer off.
Now, im only using the O2 enhancer to maintain normal readings. I'd like to just start increasing HHO production until I see some good results. After that I’ll start leaning with the MAP enhancer... I hope to see good result without leaning around 3-4 LPM. (1 LPM had no results to speak of on the 2001 GMC 3500 box van).