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Hight altitude CPS??
- Thread starter Xjcowboy
- Start date
goodburbon
NAXJA Forum User
- Location
- Westcliffe Colorado.
On the engine or in a store?
96XJ9705
NAXJA Forum User
- Location
- California
CPS = crank position sensor?
Blaine B.
NAXJA Forum User
- Location
- Northwest Indiana
or cam position sensor.....?
I didn't know either mattered with high altitude. The crank position sensor is just a magnet!
I didn't know either mattered with high altitude. The crank position sensor is just a magnet!
philip_g
NAXJA Forum User
- Location
- back in CO
the local parts shops sell the straight low alt model. the high alt you'd have to get from a dealer for 140 bucks or so.
xjbubba
NAXJA Member # 1524
- Location
- santa barbara, ca
Anyone know the difference between a "high altitude sensor" (how high?) and the normal sensor?
Harlee&Tahoe
NAXJA Forum User
- Location
- South Lake Tahoe, CA
iirc pickup is moved to advance timing
5500ft. (oops it's 4000ft)
I'm trying to find picture for my emmisions con. info. sticker. Which also states I have a "XG" dosen't state "XJ"
I'll post pic later I have to go to work now.
5500ft. (oops it's 4000ft)
I'm trying to find picture for my emmisions con. info. sticker. Which also states I have a "XG" dosen't state "XJ"
I'll post pic later I have to go to work now.
Last edited:
Hellbent
NAXJA Forum User
- Location
- san diego, california
yep...the sensor is offset slightly on it's bracket(relative to the "standard" cps) to advance the base timing.
1985xjlaredo
NAXJA Forum User
- Location
- Kansas City
Hmm never new that. Can you change the different ones out?
goodburbon
NAXJA Forum User
- Location
- Westcliffe Colorado.
yes you can change them out but only on the earlier models, OBD II vehicles only have one available CPS
Hellbent
NAXJA Forum User
- Location
- san diego, california
yeah, i should have mentioned that...only on the renix rigs. although i saw something somewhere, i think someone was modifying stock late model cps's by elongating the mounting holes. i don't think i'd want to get into that...
- Location
- on the beach in Ocean View, VA
I've often considered elongating them and playing with slight timing adjustments-- if it wasn't such a royal PITA to adjust it, that'd be a fun project!
Any guesses how much advance is built into the high alt. CPS? I guess that would still be OEM tech, just a modified OEM tech!
--Shorty
Any guesses how much advance is built into the high alt. CPS? I guess that would still be OEM tech, just a modified OEM tech!
--Shorty
Hellbent
NAXJA Forum User
- Location
- san diego, california
iirc, i believe that it was 5* advanced...
- Location
- on the beach in Ocean View, VA
same flexplate, same bellhousing, diff CPS-- all advance is from position of pick-up on bracket?? yes? Seems like an oval mount that poistions the pick-up anywhere between standard location and high alt position would give me 5* adjustable timing...hmmm..
time to investigate if the ECU will slowly re-learn the new position and retard the timing back to normal.... hell, I live AT sea level (actually 100 yards from the water and 11' above sea level), I might even try a degree or two less than factory and see if the bottom end will pick up anything!
Damnit, now I've gotta start researching and thinking again-- I'm a recovering thinkaholic and I'm about to fall off the wagon!:doh: I'm startin' to hate Renix, 'cuz it keeps making me think I can outsmart it and find the hidden potential that I'm sure is still there for the taking-- I swear it was designed by the smartest guy in the world and he built "just enough" safety into it to keep it as reliable as a claw hammer--but at the expense of power. I know he's just sitting back waiting for the first person to find the silver bullet that makes it everything the "beancounters" didn't allow it to be!
--Shorty
time to investigate if the ECU will slowly re-learn the new position and retard the timing back to normal.... hell, I live AT sea level (actually 100 yards from the water and 11' above sea level), I might even try a degree or two less than factory and see if the bottom end will pick up anything!
Damnit, now I've gotta start researching and thinking again-- I'm a recovering thinkaholic and I'm about to fall off the wagon!:doh: I'm startin' to hate Renix, 'cuz it keeps making me think I can outsmart it and find the hidden potential that I'm sure is still there for the taking-- I swear it was designed by the smartest guy in the world and he built "just enough" safety into it to keep it as reliable as a claw hammer--but at the expense of power. I know he's just sitting back waiting for the first person to find the silver bullet that makes it everything the "beancounters" didn't allow it to be!
--Shorty
I have two other thread going, all related.
Long story short -
Went to store. Dumped cheap injector cleaner in full tank.
waited 30 minutes to install less-used CPS to repair high rpm power loss.
Engine would hardly run at all.
Replaced with "working" CPS.
no fix.
Changed fuel filter.
no fix.
stumped.
Running so far off spec, Cat is glowing.
Bad.
Long story short -
Went to store. Dumped cheap injector cleaner in full tank.
waited 30 minutes to install less-used CPS to repair high rpm power loss.
Engine would hardly run at all.
Replaced with "working" CPS.
no fix.
Changed fuel filter.
no fix.
stumped.
Running so far off spec, Cat is glowing.
Bad.
Hellbent
NAXJA Forum User
- Location
- san diego, california
i don't think the computer would dial back the timing after the hi-alt cps. if it did, why would the factory have offered a different version to begin with? i believe the computer adjusts the timing from the "base" reading onward. change the base timing and all adjustments go up from that new reference point. made quite a difference on my '88, i never checked it with a timing light, but even after 10,000 miles it never felt like it went back to "stock".
this is interesting.
sounds like a VERY picky gap going on here...
http://autorepair.about.com/library/a/1i/bl534i.htm
sounds like a VERY picky gap going on here...
http://autorepair.about.com/library/a/1i/bl534i.htm
Hellbent
NAXJA Forum User
- Location
- san diego, california
some of them are VERY picky about distance. some of the late model jeep cps's have a little installation distance-pad-thingy on the bottom that gets knocked off upon start-up, it's something like .025 thick. i know the signal of the cps disappears exponentially as the gap increases. something about square waveform signals-definitely has an effect, although that's not really my bag. that sounds like 5-90's department.
