2nd Gen Ram Tech 1994-2001 Rams: This section is for TECHNICAL discussions only, that involve the 1994 through 2001 Rams. For any non-tech discussions, please direct your attention to the "General discussion/NON-tech" sub sections.

What are the symptoms of a bad map sensor

Thread Tools
 
Search this Thread
 
Old May 20, 2009 | 09:23 AM
  #1  
mcss8541's Avatar
mcss8541
Thread Starter
|
All Star
Joined: Feb 2007
Posts: 946
Likes: 1
From: EL CAMPO, TX
Arrow What are the symptoms of a bad map sensor

I think my MAP sensor might either be bad or going bad. What are some symptoms of this?
 
Reply
Old May 20, 2009 | 05:16 PM
  #2  
mcss8541's Avatar
mcss8541
Thread Starter
|
All Star
Joined: Feb 2007
Posts: 946
Likes: 1
From: EL CAMPO, TX
Default

Anyone want to give me a hand with this or how do i check my current one
 
Reply
Old May 20, 2009 | 07:19 PM
  #3  
jasonw's Avatar
jasonw
Site Moderator
Joined: Jan 2008
Posts: 8,374
Likes: 28
From: Sioux Falls, SD
Default

Search Youtube for how to check a MAP sensor. There are some very good tutorials on there (thats what I did).

A bad MAP sensor can potentially cause all sorts of issues...
1. A rich or lean fuel mixture. You may notice a gas smell even after warm-up and/or pinging at random times or all the time or whenever.
2. Excessive fuel consumption (rich)
3. Rough idle
4. Hesitation

You will especially notice the hesitation off of idle when you first give it gas. The engine may even die if you don't give it enough gas off of idle.

Usually when a MAP goes bad, you get a CEL and a code for it.
 
Reply
Old May 21, 2009 | 11:24 AM
  #4  
mcss8541's Avatar
mcss8541
Thread Starter
|
All Star
Joined: Feb 2007
Posts: 946
Likes: 1
From: EL CAMPO, TX
Default

Originally Posted by jasonw
Search Youtube for how to check a MAP sensor. There are some very good tutorials on there (thats what I did).

A bad MAP sensor can potentially cause all sorts of issues...
1. A rich or lean fuel mixture. You may notice a gas smell even after warm-up and/or pinging at random times or all the time or whenever.
2. Excessive fuel consumption (rich)
3. Rough idle
4. Hesitation

You will especially notice the hesitation off of idle when you first give it gas. The engine may even die if you don't give it enough gas off of idle.

Usually when a MAP goes bad, you get a CEL and a code for it.
thanks Jason will do.
 
Reply
Old Aug 11, 2010 | 09:20 PM
  #5  
intrepid88's Avatar
intrepid88
Registered User
Joined: Aug 2010
Posts: 16
Likes: 0
Default

hello can i have a bad map sensor IF THE ENGINE LIGHT IS NOT ON IS THAT POSSIBLE.. MY CAR SYMTOMS ARE POOR ACELERATION HEAD LIGHTS GET DIM IN STOP COULD THIS BE A MAP SENSOR I REPLACE THE MAP SENSOR BUT THE SENSOR WAS FOUND IN THE JUNK YARD FOR 20 BUCKS.... IN AUTOZONE IS 94 DOLLARS ...
 
Reply
Old Aug 11, 2010 | 09:43 PM
  #6  
cmckenna's Avatar
cmckenna
Record Breaker
Joined: Jul 2009
Posts: 1,093
Likes: 6
From: Near NY for another contract
Default

No way. This is part of the EFI system. If your lights are going dim, that's either a FAULT with the charging system or, a poor connection someplace either due to a bad ground or HOT.

Check and clean all BAT connections, all ground connections first and retest.

If these connections are showing high resistance, a voltage drop will occur and, depending on how low the voltage is dropping, there's a possibility that it is also affecting the PCM.

CM
 
Reply
Old Aug 11, 2010 | 09:51 PM
  #7  
cmckenna's Avatar
cmckenna
Record Breaker
Joined: Jul 2009
Posts: 1,093
Likes: 6
From: Near NY for another contract
Default

The MAP sensor is what measures the manifold pressure. Manifold Absolute Pressure sensor. This is another master sensor that provides voltage to the PCM. This voltage reading determines in part, what the A/F mixture should be.

In addition to that, it also plays a part in determining the spark advance and injector pulse width. The PCM uses the MAP sensor to determine or calculate the following:

- Manifold Pressure
- Barometric Pressure
- Engine Load
- Injector Pulse Width
- Spark Advance programs
- Shift point strategies for specific auto transmissions
- Idle speed
- Decel fuel shutoff

CM
 
Reply
Old Aug 12, 2010 | 12:24 AM
  #8  
jasonw's Avatar
jasonw
Site Moderator
Joined: Jan 2008
Posts: 8,374
Likes: 28
From: Sioux Falls, SD
Default

Could be a bad alternator or bad battery, or a bad ground. A bad MAP would definitely not cause the lights to dim. I would follow cmckenna's instructions, he's very good at what he does.
 
Reply
Old Jan 9, 2011 | 11:54 AM
  #9  
robinhood's Avatar
robinhood
Registered User
Joined: Nov 2010
Posts: 7
Likes: 0
Default

Hi everyone i need help i have a 98 durando i bought it cuz good price and iam a fairly good mech or least i thought i was till this can into my life lol
my 98 had starting problems the old owner took to dodge the said after hours of testing the the think it needs a pcm ( but cant garintee it it is that ) so the 500 plus 800 for pcm with no garintee she says no way tows it home puts it for sell i buy thinking iam this great mech il fix it lmfao this dodge is winning. wen i first got it home no start at all this is a list of what i have done
#1 used pcm
#2new crank sen
#3 new can cap and rotor
#4 got oringenle pcm reflashed
#5 picked up anoth used pcm ( that a totle of 3 ) now
#6 i get two more reflashed
ok now what it is doing it starts then dies right away
please if there is any body out there that can piont me it the right way i dont like dealer ships there just part replacers not mech and i know they know this a reacureing problem they dont care as long as you need them i think we as dodge owner get to gether as one grope and solfe this problem i think with all our knolage we could my email is robinhood-25@hotmail.com or robert steffen on face book iam the one with the two dogs in pic look me up lets chat about the durango and solf this thing
 
Reply
Old Jan 9, 2011 | 12:38 PM
  #10  
HeyYou's Avatar
HeyYou
Administrator
Veteran: Air Force
Community Favorite
15 Year Member
Community Builder
Joined: Apr 2010
Posts: 87,468
Likes: 4,220
From: Clayton MI
Default

Try swapping out the ASD, and fuel pump relays, with some others under the hood. See if anything changes.
 
Reply



All times are GMT -4. The time now is 10:11 AM.