Anyone ever have a Bap sensor go bad on them? What symptoms did you have that lead you to the bap?
And are the 2.3 bap sensors the same as the 5.0s?
And are the 2.3 bap sensors the same as the 5.0s?
Bap Sensor?
- Thread starter Scott_B
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BAP sensors that outright fail will post code 22
Code 22 MAP (vacuum) or BARO signal out of range. The MAP or BARO sensor is pretty much the same sensor for both Mass Air & Speed Density cars. The main difference is where it is connected. Mass Air cars vent it to the atmosphere, while Speed Density cars connect it to the intake manifold vacuum. Its purpose is to help set a baseline for the air/fuel mixture and changes in barometric pressure. The MAP or BAP sensor puts out a 5 volt square wave that changes frequency with variations in atmospheric pressure. The base is 154 HZ at 29.92" of mercury - dry sunny day at sea level, about 68-72 degrees. You need an oscilloscope or frequency meter to measure it.
Baro or MAP test using frequency meter - run the test key on engine off. The noise from the ignition system will likely upset the frequency meter. I used a 10 x oscilloscope probe connected from the frequency meter to the MAP/BAP to reduce the jitter in the meter's readout.
If it is defective, your air/fuel ratio will be off and the car’s performance & emissions will suffer
Code 22 MAP (vacuum) or BARO signal out of range. The MAP or BARO sensor is pretty much the same sensor for both Mass Air & Speed Density cars. The main difference is where it is connected. Mass Air cars vent it to the atmosphere, while Speed Density cars connect it to the intake manifold vacuum. Its purpose is to help set a baseline for the air/fuel mixture and changes in barometric pressure. The MAP or BAP sensor puts out a 5 volt square wave that changes frequency with variations in atmospheric pressure. The base is 154 HZ at 29.92" of mercury - dry sunny day at sea level, about 68-72 degrees. You need an oscilloscope or frequency meter to measure it.
Baro or MAP test using frequency meter - run the test key on engine off. The noise from the ignition system will likely upset the frequency meter. I used a 10 x oscilloscope probe connected from the frequency meter to the MAP/BAP to reduce the jitter in the meter's readout.
If it is defective, your air/fuel ratio will be off and the car’s performance & emissions will suffer
Dbeck002
New Member
The BAP sensor
AKA B1tch Ass Police sensor is located right above the dash near the rear view mirror, its usually plugged into the cigarette lighter outlet...
AKA B1tch Ass Police sensor is located right above the dash near the rear view mirror, its usually plugged into the cigarette lighter outlet...
Black1987Stang
Active Member
jrichker said:
Jrichker, if i have a code 22 does it mean its bad for sure and I have to get a replacement? I dont have a frequency meter but could i test it as a MAP sensor by reading the output voltage at different vacuums? It looks like im going to have to find a replacement. I can unplug it and everything is the excat same.
The code 22 means the computer isn't recieving a signal from the MAP/BARO sensor. That can mean bad wiring (no +5 volts on the orange sensor power wire) or a broken wire between the sensor and the computer. It can also mean that MAP/BARO sensor itself has failed.87stangdiddle said:
The MAP and BARO sensors are the same type of sensor. Both produce a 5 volt peak to peak square wave that varies in frequency with the vacuum/pressure applied to the port. The voltage output remains constant at 5 volts, +/- 0.25 volt as the waveform changes frequency. The only way to check the sensor output is with either a frequency counter or oscilloscope.
Paul Perreca
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- Mar 30, 2005
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Black1987Stang
Active Member
jrichker said:
I have a good 5volt reference signal going to the Bap sensor and I have a good ground also. I checked the voltage at the signal wire (green wire i think) at an idle (I didnt no better about needing a frequency meter), and at idle i got 2.69 volts and i revved it up a little and it went up to 2.89 volts. Does this mean anything bad? Just before my car was running very lean mostly at idle and it was surging like it had a cam with .800in of lift or something. There was alot less power and it just was slow in throttle response, so i pulled the codes...heres what i got...Hard Codes
32-Evp voltage low(SONIC)/EPT circuit voltage low(PFE)
82-Air diverter solenoid circuit fault or supercharger bypass valve
95-Fuel Pump secondary circuit fault (Should be b/c i havent put in a fp monitor signal since i did my mass air swap)
Continous Memory
22-MAP/BARO sensor out of range
29-Insufficient input from the VSS(havent hooked in signal from mass air swap)
32-EVP voltage low
66-MAF below minimum voltage or at fault
95-FP secondary circuit fault (no fp signal from mass air swap)
after i pulled the codes i disconnected the battery for 15 minutes and reconnected it and now it runs like a new car, no surging, not running lean, awesome throttle response, tons of power etc. Whats going on here? whats causing it to run like crap then after i reconnect the battery it runs amazing.
"lol he's talkin bout a radar detector bap lol i think..? lol haha"
lol no hes talking about the Barometric Atmospheric Pressure sensor
Black1987Stang
Active Member
There is no way you can properly check the MAP/BARO sensor without a frequency counter or oscilloscope. Using a voltmeter just gives you and average value of the voltage output. You could have 2.82 volts DC with no square wave output. Or you might have a square wave output and not enough voltage to trigger the computer's input threshold level. A true RMS voltmeter won't even work correctly with a square wave, since most of them are design to measure sine waves.87stangdiddle said:
Code 32 - Code 32 – EGR voltage below closed limit
Let’s put on our Inspector Gadget propeller head beanies and think about how this works:
The EGR sensor is a variable resistor with ground on one leg and Vref (5 volts) on the other. Its’ resistance ranges from 4000 to 5500 Ohms measured between Vref & ground, depending on the sensor. The center connection of the variable resistor is the slider that moves in response to the amount of vacuum applied. The slider has some minimum value of resistance greater than 100 ohms so that the computer always sees a voltage present at its’ input. If the value was 0 ohms, there would be no voltage output. Then the computer would not be able to distinguish between a properly functioning sensor and one that had a broken wire or bad connection. The EGR I have in hand reads 700 Ohms between the slider (EPV) and ground (SIG RTN) at rest with no vacuum applied.
As vacuum is applied, the voltage on the slider increases (EVP). As the voltage increases, the computer knows the how much the EGR valve is opened and how much exhaust gas is being recirculated. It uses the load table to calculate the amount of exhaust gas required depending on RPM, Mass Air Flow, ACT, ECT & TPS. It then sends a signal to the Electronic Vacuum Regulator to hold, increase or decrease the vacuum being applied to the EGR valve.
Theory class is over now, let’s spin up our propeller head beanies and get with it… Go Gadget, Go…
Measure the resistance of the EGR sensor between the two end pins. You should see between 3500 to 5500 Ohms. With the sensor removed, measure the resistance again while pressing on the plunger. You should see the resistance drop from its high value to a low reading of 200-700 ohms depending on the sensor. No resistance readings, or values way out of range, the sensor is bad.
If the orange/white wire does not have Vref (5 volts =/-.25 volt), then you have some wiring problems in the circuit that supplies power to the sensor.
If you do have +5 volts on the orange /white wire, the sensor is getting power. The computer isn’t seeing the minimum voltage on the EVR pin 27: that’s an indication of wiring problems. Ohm the wiring back to the computer. Check for resistance between the brown/lt green wire on the EGR sensor and pin 27 on the computer: you should have less than 1 ohm. Repeat the process for the orange/white wire and pin 26. Do it again between the black/white wire and pin 46. In no case should you have more than 1 ohm. Remember that resistance checks are always done with the power off the circuit.
Voltage and resistance checks are good: Here’s an EGR test procedure I copied from cjones
to check the EGR valve:
bring the engine to normal temp.
connect a vacuum pump to the EGR Valve
apply 5 in vacuum to the valve.
if engine stumbled or died then EGR Valve and passage(there is a passageway through the heads and intake) are good.
if engine did NOT stumble or die then either the EGR Valve is bad and/or the passage is blocked.
if engine stumbled, connect vacuum gauge to the hose coming off of the EGR Valve
snap throttle to 2500 RPM’s (remember snap the throttle don't hold it there).
did the vacuum gauge show about 5 in vacuum?
if not, check for manifold vacuum at the EGR vacuum valve.
if you have manifold vacuum then connect vacuum gauge to the EGR valve side of the vacuum valve and snap throttle to 2500 RPM’s.
should read about 5 in vacuum
End of cjones's test.
If the test procedure fails to provide proper vacuum, check vacuum feed lines for cracks & damage. If the vacuum lines are good, check the electrical wiring to the EVR. If the EVR electrical wiring is good, look for 12 volts on the red wire for the EVR. If the 12 volts is good, look for a varying voltage on the dark green wire on the EVR. Case of last resort, replace the EVR and then the computer
Code 66 MAF below minimum test voltage.
Insufficient or no voltage from MAF. Dirty MAF element, bad MAF, bad MAF wiring, missing power to MAF. Check for missing +12 volts on this circuit. Check the two links for a wiring diagram to help you find the red wire for computer power relay switched +12 volts. Check for 12 volts between the red and black wires on the MAF heater (usually pins A & B). while the connector is plugged into the MAF. This may require the use of a couple of safety pins to probe the MAF connector from the back side of it.
There are three parts in a MAF: the heater, the sensor element and the amplifier. The heater heats the MAF sensor element causing the resistance to increase. The amplifier buffers the MAF output signal and has a resistor that is laser trimmed to provide an output range compatible with the computer's load tables.
The MAF element is secured by 2 screws & has 1 wiring connector. To clean the element, remove it from the MAF housing and spray it down with electronic parts cleaner or non-inflammable brake parts cleaner (same stuff in a bigger can and cheaper too).
The MAF output varies with RPM which causes the airflow to increase or decease. The increase of air across the MAF sensor element causes it to cool, allowing more voltage to pass and telling the computer to increase the fuel flow. A decrease in airflow causes the MAF sensor element to get warmer, decreasing the voltage and reducing the fuel flow. Measure the MAF output at pins C & D on the MAF connector (dark blue/orange and tan/light blue) or at pins 50 & 9 on the computer.
At idle = approximately .6 volt
20 MPH = approximately 1.10 volt
40 MPH = approximately 1.70 volt
60 MPH = approximately 2.10 volt
Check the resistance of the MAF signal wiring. Pin D on the MAF and pin 50 on the computer (dark blue/orange wire) should be less than 2 ohms. Pin C on the MAF and pin 9 on the computer (tan/light blue wire) should be less than 2 ohms.
There should be a minimum of 10K ohms between either pin C or D on the MAF and ground.
See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host)
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif
http://www.veryuseful.com/mustang/tech/engine/images/88-91eecPinout.gif
http://www.autozone.com/servlet/UiB..._us/0900823d/80/19/59/5a/0900823d8019595a.jsp
Code 82 – Secondary Air Injection Diverter Solenoid failure AM1. The dump valve air diverter valve (front vacuum operated valve) isn’t working on the Thermactor Air System (smog pump). Look for broken or missing vacuum lines on the solenoid valve to the diverter valve Check the solenoid valve for +12 volts at the Red wire and look for the Red/White wire to switch from +12 volts to 1 volt or less. The computer controls the valve by providing a ground path on the Red/White wire for the solenoid valve
Look closely at the code 66 & the code 22. You car will run poorly until you get them fixed. The run good after clearing the codes is because when you clear the codes, you clear the run in limp mode flag that codes 22 & 66 set.
Black1987Stang
Active Member
Thanks alot for that info...although i cant test any of my wires right now because my DMM broke. I have to exchange it for a new one tomorrow. It happened again tonight Very bad though, my car was surging like crazy, seemed like my timing was way off my vacuum had gone down to like 8 inches HG just at idle at one time. I pulled the codes and got like 4 more stored codes along with the ones i had before. Since i dont have the money for a new all new parts and dizzy (to check my pip about my timing problem) Im going to try one from another mustang. Anybody want to be a fellow TN stanger and let me try your map sensor, maf or dizzy on my car? Or try my parts on ur car. PLEASE!!!
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