Go Back   Ford F150 Forum - Community of Ford Truck Fans > Pre-1997 F150 > 1987 - 1996 F150
Sign in using an external account
Register Forgot Password?

Computer and Map sensor problems

Thread Tools Search this Thread Display Modes
Old 08-21-2010, 01:04 PM   #1
Join Date: Mar 2010
Location: Miami Texas
Posts: 53
Mentioned: 0 Post(s)
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Default Computer and Map sensor problems

1994 Ford F150 XL, 4.9 engine

Since purchasing my truck, I have had nothing but problems with the Map Sensor and the computer on the truck.

I have replaced the map sensor three times and the computer once already. The check engine light will come on and then very shortly the truck will start lurching, spitting and sputtering and running really bad. You can smell the fumes from the exhaust and the gas will start mixing incorrectly. It will die when stopped and is hard to get restarted at times. Engine has 69000 miles on it and does not smoke or use any oil at all.

I have taken it to a professional mechanic each time it has acted up and all the testing equipment will show either the map sensor or computer is the problem, but changing the sensor and computer out has not solved the problems as of yet.

Anyone else had this problem and what did you finally do to solve the problems. Both myself and the mechanic are getting really frustrated with this.

Thank you,

Miami Texas
NobbyofTexas is offline   Reply With Quote
Old 08-21-2010, 01:21 PM   #2
Assistant Administrator
5 Year Member
ymeski56's Avatar
Join Date: Jul 2008
Location: Long Beach Calimexifornia
Posts: 32,203
Mentioned: 17 Post(s)
Thanked 726 Times in 420 Posts
Feedback Score: 0 reviews

Not that I don't trust most mechanics to preform the KOEO (key on engine off) & KOER (key on engine running) scans correctly but......OK, I don't!
I would do the scans manually as directed at the top of the page, or buy a $22. code reader w/ digital display. Need to do the KOEO first, & most mechanics don't even do it at all. They go right to the KOER. Big mistake! http://www.handsontools.com/Equus-In...ol_p_5574.html
We really need the actual code #'s & which scan they appear in. And if their a continuous memory code, or an active code, or both.

t will probably end up being either a compromised sensor wire to or from the MAP sensor if I had to guess. You can check that separately.http://www.fordfuelinjection.com/?p=27

What happens when you disconnect the connection to it (not the vac, just the wire connection)? No change? Check input voltage.
"Saving the World....One Ford Truck at a Time."

Last edited by ymeski56; 08-21-2010 at 01:39 PM.
ymeski56 is online now   Reply With Quote
Old 08-21-2010, 01:25 PM   #3
We'd do it
Just call me Sean's Avatar
Join Date: May 2008
Location: Orlando,Fl.
Posts: 32,276
Mentioned: 3 Post(s)
Thanked 408 Times in 364 Posts
Feedback Score: 1 reviews
Send a message via Yahoo to Just call me Sean

Yes, post the codes. Possibly bad wiring.
Originally Posted by Early Cuyler
Fights begin, fingerprints are took, days is lost, bail is made, court dates are ignored, cycle is repeated.
Just call me Sean is offline   Reply With Quote
Old 08-21-2010, 01:25 PM

Similar Threads
Thread Thread Starter Forum Replies Last Post
Camshaft sensor problems on 3v 5.4 colt4554 2004 - 2008 Ford F150 3 05-13-2014 07:06 AM
Question about Oil pressure sensor,or fake sensor posttal 2004 - 2008 Ford F150 3 03-23-2010 03:24 PM
computer problems roninbrad General F150 Discussion 0 01-17-2010 10:51 AM
Back up sensor problems jpoirier General F150 Discussion 0 09-16-2009 09:06 AM
MAF Sensor Problems?? L.Jimmy 1987 - 1996 F150 3 05-23-2009 03:13 PM

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Join F150 Forum


The Mustang Source

All times are GMT -4. The time now is 07:25 PM.

Copyright 2006 - 20011 F150forum.com
This site is in no way affiliated with the Ford Motor Company.