Just replaced cam, installed a CompCam 250H extreme 4x4 cam shaft. I had the engine completely rebuilt professionally, and we think I am going to need to install a map sensor Adjuster to compensate for fuel mixture. Has any one run into this issue, and does anyone carry these in the DFW area? Thanks in advance, Terry
Map Sensor ???
- Thread starter 360-gpn
- Start date
eflores
NAXJA Forum User
- Location
- Greg's place
i know how to build um.....parts cost about 15 bucks
5-90
NAXJA Forum User
- Location
- Hammerspace
The MAP sensor is fed a +5VDC reference voltage, and is a variable resistance that divides that voltage per manifold pressure (MAP = Manifold Absolute Pressure.)
The "Adjustable MAP Sensor" is little more than an LM317-derived circuit that is adjustable to provide a variable voltage - the +5VDC is fed into the circuit as a supply, and the output is varied according to the regulator.
OK - you feed the thing +12VDC, not +5VDC. Still, the rest of the principles are the same. Be sure to heat-sink the LM317, it do get a bit warmish...
http://www.go.jeep-xj.info/HowtoMAPsensor.htm
The "Adjustable MAP Sensor" is little more than an LM317-derived circuit that is adjustable to provide a variable voltage - the +5VDC is fed into the circuit as a supply, and the output is varied according to the regulator.
OK - you feed the thing +12VDC, not +5VDC. Still, the rest of the principles are the same. Be sure to heat-sink the LM317, it do get a bit warmish...
http://www.go.jeep-xj.info/HowtoMAPsensor.htm
eflores
NAXJA Forum User
- Location
- Greg's place
.... not a highly gaurded secret
eflores
NAXJA Forum User
- Location
- Greg's place
did you break it in properly?
Haven't had a chance, haven't had it running long enough yet. My mechanic is coming over next week to install the Maps adjuster and to hopefully fine tune it. We are going by the book on this one as far as break-in goes. I'd like to have it ready for the next 
run.
run.
eflores
NAXJA Forum User
- Location
- Greg's place
too bad you arent closer or id come help ya break it in right
- Location
- Richardson, TX
Come show it off to me sometime! :sunshine:
eflores
NAXJA Forum User
- Location
- Greg's place
ya im in wichita falls....come down one weekend....we do informal little get togethers about once a month, the house looked like a jeep convention this weekend
MischiefMan
NAXJA Forum User
- Location
- Denton, Texas
psst..hey Flores, turn your map over man...WF is UP from the Metroplex....we go UP to WF, not DOWN to WF.
eflores
NAXJA Forum User
- Location
- Greg's place
lol up down blah its all relative
Last edited:
MischiefMan
NAXJA Forum User
- Location
- Denton, Texas
Dude.....seriously, we don't need to know what you do with your relatives!!!
Tough Trucks came over to the house yesterday and installed the Map Adjuster. Chris did a nice job on this thing, looks like it belongs there. They fine tuned it and got 80 to 85% of the miss out of it. I still feel it at cruising speed. So I am going to replace the TPS today and see what happens. I'm pretty happy with the performance so far, and as it breaks in it will only get better. I have to remember that I've got a brand new heart in this this still surrounded by 20 year old stuff, it will just take some time to work it all out. But I've got no complaints so far. I'll get some pix up soon as I can.
