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2000 Chevy Monte Carlo LS 3.4 V6. Replaced the MAF and Map Sensor after codes appeared. Problem is persisting, symptoms include a sputtering engine with a fuel smell. Code states Map Sensor - High Input

if it's the same code, check

if it's the same code, check and rule out wiring/connector or ground problems, onece your sure there's on wiring problems, replace computer.
if it's a high circuit code, thats means the computer didn't see a voltage drop when cond. in engin changed and the voltage stayed high.
most likely a wiring problem on the circuit supply wire.

Starting car work at 7am EST,

Starting car work at 7am EST, will let you know what the voltmeter reads. Also going to check for vacuum leaks using hand vacuum pump. If its the computer then the car is going up for sale. I dont have the money for that.

darrelyoungdy, You could have


You could have made the mistake that most individuals make. That is to change a sensor (or sensors) just because a code (or codes) are set. Just because a code is set, doesn’t mean the sensor has failed.


Wiring issues with sensors
Circuit issues with sensors
Wire connector issues with sensors
PCM issues

The “PCM” doesn’t know the difference between the above mention and a failed sensor. It simply recognizes an error, tries to compensate or adjust for it, then when (and if) it cannot, the PCM will set the “MIL”. There are quite a few things that could be causing the sputtering engine and fuel smell.

The fuel smell is an indication of a rich burn
The sputter is from the rich burn

There is also a strong possibility that the sputtering engine and fuel smell have nothing to do with the codes that are set.


Ambient air issues
Issues with fuel pressure and volume
Engine vacuum issues
EGR issues
Fuel injector issues
Spark plug issues
Exhaust back pressure issues

Check each sensor individually, and remember a part (any part) must never replaced until it checked and confirmed defective.


let me know if you run into a

let me know if you run into a problem.

The code error coming up is

The code error coming up is DTC P0108. I'm going to run a vacuum and voltage check on the wires from the MAP sensor. Right now this is my method of thinking:

1.) Bad wiring from signal (green wire)
2.) Open or stuck EGR valve
3.) Loose PCV Valve
4.) Wire failure at ECM to MAP
5.) Failed ECM

that code is a circuit code,

that code is a circuit code, so sitck with checking wiring.
high means the 5 votl singal has not changed, so it's probley a open in the singal wire.

darrelyoungdy, One way to


One way to determine engine load is for a MAP sensor to monitor the changes in intake vacuum. Vacuum should drop off at acceleration and, WOT (wide open throttle), and should be it’s highest at idle. As engine load increases, intake vacuum should drop off. A PCM will use the MAP sensor input to change timing and air fuel ratios. A MAP sensor issue will frequently cause:

Poor fuel economy
Engine hesitation
Engine surges
Other drivability and performance issues

As engine vacuum loads change a MAP sensor will either generate a voltage or frequency that relates to the change in engine vacuum. Vacuum leaks are the number one cause for issues with MAP sensor readings, so it is critcal to (RULE OUT VACUUM LEAKS)early in your diagnosis.

Tested all the vacuum tubes

Tested all the vacuum tubes and they are fine. Did the voltage reading on the signal wire (green) and came to 7.14 on initial reading. Pushed 5 in. Mg and no drop, continued to push increments of 5 in. Mg all the way to 20 in. and no drop occurred in voltage. So my assumption is the green wire has is open and not signaling the PCM

check continuity of the wire

check continuity of the wire from the connector at the ecm to the connector at the map sensor.

Im done with it, I dont want

Im done with it, I dont want to mess with the throttle body which is needed to remove the header and access the entire wire. I haven't checked the connector at the ECM. What should I be looking for at that connector? Any ideas on the price range of what this fix costs at a dealership?

just use a ohm meter and put

just use a ohm meter and put one lead on the term. for the map sensor at the ecm connector and the other lead to the same wire in the map sensor's connector.
you should get a reading of .01+/-.03 ohms, if not run a new wire fron connector to connector.
if you need connectors views, let me know.

If you can post connector

If you can post connector views that would be good, could you also post a pic of an ohm meter. I have a multi-meter I dont know if they are the same. What setting should I use as well if they are the same, DC?

Darrelyoungdy, There’s a


There’s a strong chance you’re not checking the MAP correctly. You stated that you pumped in vacuum and you didn't see a voltage drop. Well you could have just confirmed that the MAP is “Defective”. You never stated if you installed a new MAP, but understand that even a new part can be defective. Furthermore you stated you checked all the vacuum tubes and you found no leaks. Well that's definitely wrong. There are many places (besides tubes or hoses) on an engine for vacuum to escape. Below are just three off the top of my head.

Intake manifold gasket
Grommet at PCV valve
Grommet at Check Valve for brake booster

Check for vacuum leaks using an (ENGINE VACUUM PRESSURE GAUGE) and post the results.


With your scan tool, look at the short term and long term fuel trims. The normal range is plus or minus 8. If the numbers on the short term are plus 10 or higher for the short and long term, the engine is running lean. Now if you if you rev the engine to 1500 or 2000 rpm and hold it there for a minute or so, and the short term fuel trim drops back down to a more normal reading, (THAT CONFIRMS AN ENGINE VACUUM LEAK AT IDLE).


If the reference wire is not supplying the specified voltage, check the voltage on this wire at the computer. If the voltage is within specifications at the computer, but low at the sensor, repair the reference wire. When this voltage is low at the computer, check the voltage supply wires and ground wires on the computer. If these wires are satisfactory, replace the computer. With the ignition switch on, connect the voltmeter from the sensor ground wire to the battery ground. If the voltage drop across this circuit exceeds specifications, repair the ground wire from the sensor to the computer. Back probe the MAP sensor signal wire and connect a voltmeter from this wire to ground with the ignition switch on. The voltage reading indicates the barometric pressure signal from the MAP sensor to the computer. Many MAP sensors send a barometric pressure signal to the computer each time the ignition switch is turned on and each time the throttle is in the wide-open position. If the voltage supplied by the barometric pressure signal in the MAP sensor does not equal the vehicle manufacturer's specifications, replace the MAP sensor.

To check the voltage signal of a MAP, turn the ignition switch on and connect a voltmeter to the MAP sensor signal wire. Connect a vacuum pump to the MAP sensor vacuum connection and apply 5 in. Hg (127 mm Hg) of vacuum. On some MAP sensors, the sensor voltage signal should change 0.7 to 1.0 volt for every 5 in. Hg (127 mm Hg) of vacuum change applied to the sensor. With 5 in. Hg (127 mm Hg) of vacuum applied to the MAP sensor, the voltage should be 3.5 volts to 3.8 volts. When 10 in. Hg (254 mm Hg) of vacuum is applied to the sensor, the voltage signal should be 2.5 volts to 3.1 volts. Check the MAP sensor voltage at 5-inch (127-mm) intervals from 0 to 25 inches (635 mm). If the MAP sensor voltage is not within specifications at any vacuum, replace the sensor. To check a MAP sensor with a lab scope, connect the scope to the MAP output and a good ground. When the engine is accelerated and returned to idle, the output voltage should increase and decrease.

There is a new Map installed,

There is a new Map installed, and the first one I bought was defective and I replaced it with one right from Chevrolet. The green signal wire was measuring 7.14 with no drop when vacuum was added, the other 2 wires measured 0.00. I understand how they should drop when vacuum is added. My diagnosis is a bad signal from the Map to the PCM, im going to run the same voltage test at the PCM, if it measures where it should then that will confirm that the wire is defective at the Map side.

as i said, pics donn't post

as i said, pics donn't post here, can send info to a email ad.
and if the reading you are getting is over 5 volts, then is a short to voltage in the wiring or a bad ecm.
that circuit only puts out 5 volts!!

I understand your “GREEN”

I understand your “GREEN” wire concerns. I didn'go back to read all the other postings, but I just want to be sure that the "Horse Is Not Being Put Miles" before the cart here.

Have You Confirmed ????

Ground from the PCM is reaching the MAP ?

A 5 VOLT REFERENCE VOLTAGE from the PCM is reaching the map?

Description and Operation

Description and Operation

The Manifold Absolute Pressure (MAP) sensor responds to changes in intake manifold pressure (vacuum). The MAP sensor signal voltage to the PCM varies from below 2.0 volts at idle (high vacuum) to above 4.0 volts with the key ON, and the engine OFF, or at wide open throttle (low vacuum).

The MAP sensor is used to determine manifold pressure changes while the linear EGR flow test diagnostic is being run, Refer to DTC P0401 Exhaust Gas Recirculation (EGR) Flow Insufficient, to determine engine vacuum level for other diagnostics and to determine Barometric Pressure (BARO) .

If the PCM detects a voltage that is lower than the possible range of the MAP sensor, DTC P0107 Manifold Absolute Pressure (MAP) Sensor Circuit Low Voltage will be set. A signal voltage higher than the possible range of the sensor will set DTC P0108 Manifold Absolute Pressure (MAP) Sensor Circuit High Voltage. An intermittent low or high voltage will set DTC P1107 Manifold Absolute Pressure (MAP) Sensor Circuit Intermittent Low Voltage or DTC P1106 Manifold Absolute Pressure (MAP) Sensor Circuit Intermittent High Voltage respectively. The PCM can also detect a shifted MAP sensor. The PCM compares the MAP sensor signal to a calculated MAP based on throttle position and various engine load factors

Grunt, The information you


The information you posted is good. However it’s to (GENERAL). In the future look for a (WEBSITE) that has more (COMPREHENSIVE) information to (COPY AND PASTE FROM), then simply post the (ENTIRE) link.

This information addresses only (ANALOG MAP SENSORS). It does not address (FORD DIGITAL MAP SENSORS).

There are countless individuals who come to this forum, (NOT AS MEMBERS) or (CONTRIBUTORS) but just as (READERS), to simply read our answers and (LEARN). Those folks could find this information (CONFUSSING).

Just my two cents as a (FRIEND) and (BROTHER).

Hi everyone, thank you for

Hi everyone,

thank you for all your input, and awesome knowledge base to guide me in fixing this issue. However, the repair is a little above my skill level.

I am having the car towed to Don Mallon Chevrolet in Norwich, CT tomorrow morning. Any idea on what this diagnosis /repair may cost? I am obviously looking for a price range.

Once again thank you all for everything. I am a Veteran of the Armed Forces and your kindness is what makes this country worth fighting for.

well, have them start with a

well, have them start with a hour diag. and see where it leads them.
post thier findings and we'll let you know if it sounds right.

So after days of testing

So after days of testing Chevy finally gave me answer...

Three things are wrong:

1.) Wiring to EGR Valve is bad
2.) Wiring to transmission from PCM is bad (Bad idle)
3.) PCM is bad

In all $792 worth of repairs

ya, thought it was going to

ya, thought it was going to be wiring, sorry on the cost, did they give you a millitary member discount?

According to the Chevy

According to the Chevy dealership they dont offer military or veterans discounts.




All you had to do was (READ) my bio to see that I’m an 81 year old “MARINE OFFICER”. The first thing is why you didn’t send me a (PERSONAL) e-mail? I get more than 900 e-mails a day. Most times I don’t respond to ¾ of them, but in the “Subject Line”, if you had written “VET NEEDS HELP” I would have responded to yours (FOR SURE).


$792.00 is a (RIP OFF)!!!!
1 and 2 are “BS” (FOR SURE)!!!!
3 is a possibility, but show me the proof !!!!

they SUCK, we offer them and

they SUCK, we offer them and even ask if you look millitary.
if they send you a HOW WAS YOUR SERVICE letter, tell them they suck.

They more than

They more than (SUCK)!!!!

Tell me where they are located. I'll go there. Find the "Service Manager".

BLOW HIS F___en head off from 1900 yards out !!!!



better yet, i just did: i

better yet, i just did:

i just spoke to a friend of mine and was told he just spent $800.00 on his chevy at your dealership, and when he asked about a discount for millitary personal, he was told chevy dealers donn't offer one.
well i work at a chevy dealer and we make sure we do, if you look millitary we ask.
shame on your dealership for telling such a lie, i will make sure i speak to our district manager about it, and will never send another costumer to your dealership, i wish now i didn't tell him to go to thr dealer.
and to think your tax dollars were used to bail you out, ungreatful bastards.

what'd you think,lol
p.s. i'll let you know if they reply to my email.

Well everyone, I appreciate

Well everyone,

I appreciate all of your comments, and couldnt be more grateful for your support. As a veteran of Operation Iraqi Freedom I want to say thank you to all of you for your support. Each day soldiers, sailors, marines, and airmen get thank you's for the services they provide to all americans but the real thank you goes to the american people who stand behind us through thick and thin and make every servicemember (past and present) proud to wear a uniform that has the U.S. Flag that signifies more than freedom it signifies a bond between people no matter what the circumstance.

As for the dealership... I don't know much about cars, I know what things are under a hood but thats about it which is why I posted here. The info on the dealer is:

Don Mallon Chevrolet
774 West Thames Street
Norwich, CT 06360
(860)889-3333 Ext. 2 (Service Dept)

I would guess as any other business, an influx of calls to the service manager about the lack of support for military would change things very quickly. I've asked twice about it, 1st time I got told "we'll check into it" a.k.a. "we have one but youre not getting it", 2nd time "i dont think we have one, let me check, no we dont offer that".

To mws919,

awesome advice, thanks for everything!where is your dealership, ill come for a second look when its fixed and maybe you could price me out what it should have cost so i can sue them.


a sincere thank you for your service, and the info requested is above.

my email is [email protected]

Darrel, Where do you (STAND)


Where do you (STAND) right now on this matter?

Do you plan to talk to a district manager and Chevrolet Customer Service?

What progress (IF ANY) has been made to satisfy you?


ASE MASTER, Nothing has been


Nothing has been done this far to satisfy me, i think the bill is outrageous.

I do not have the District Manager's contact information, nor the Chevy Customer Service.

Any info would be appreciated.

Darrel, Copy and past the


Copy and past the link below into your address box then click on go. Stay in touch with us. Keep us up to date on what “Chevrolet” plans to do about your unfair treatment. From there the “Dominos” will fall into place.


All, Just spoke to Chevy


Just spoke to Chevy Division on the phone and they gave me a bulls**t excuse:

"Due to the age and mileage on your vehicle we are unable to resolve your issue, you may write to Chevy via our P.O. Box regarding your complaint and we will do our best to assist you from that point"

- That was right from the Floor Supervisor at Chevy's National Call Center.

So, because my car is a 2000 Monte Carlo with 130K miles on it, they are unable to assist me. Therefore, they can do nothing about offering a military discount, and my rip-off of a repair cost.

darrel, How did you pay for


How did you pay for the repair? By credit card is best. When the bill comes don't pay it. Call your credit card company and tell them you're not paying the charge, because it's being "Disputed" in small claims court. At that point tell your credit card company the whole story. They could help, and be able to resolve this in your favor. If you used a check to pay for the job, then pay the fee for "Stopping The Check". Either way, credit or check, take out a claim in small claims court. I was on the phone this morning with my MARINE buddies in Connecticut. We came to the unanimous conclusion that it wouldn't serve (YOUR BEST INTERESTS) if we made a move at this time. Stay in touch with us, and keep us updated.

Semper Fidelis

like i said, i'll be speaking

like i said, i'll be speaking with our dist. manager and get back to you.

I have not yet paid for the

I have not yet paid for the service, they placed the PCM on order yesterday afternoon and it will arrive today with repairs taking until tonight or tomorrow morning at the latest according to the service department representative.

Good. Problem is you have to

Good. Problem is you have to pay first or they won't release the car. So pay for it with your credit card, then follow what I said above. Keep in touch.

Semper Fidelis

car back yet?

car back yet?