Just changed the crankshaft sensor now it jerks at 50 mph
Which engine? (asked now 1000 times, only 2 ever answered)
tune up time, spark parts, rotor to plugs. filters. both.
its called a 60k mile tune up solves most.
my guess, is its misfiring or
is this the ASD relay dropping out then back in, as driven.
jerked before and after CKP sensor, did you know its the last thing to fail......
see the list of ASD drops.
misfiring, can be felt, its like a misfiring chain saw, ever here a 2 stoke misfire, ratta, tata ,tat?
some call it jerking, its not, is misfiring. (3reasons ) and 25 causes.
but jerkin real, like if you cut the ignition that is and instant bog.
but if you off the key and back on , fast, that be a jerk
that is total power loss. not misfire. its loss spark and fuel.
and jerks hard.
so does loss of 12vdc to the EFI system.
so the first step is to see if its the ASD relay dropping out.
on all jeeps.. 93 to now.
ASD
http://www.fixkick.com/Jeeps/ASD.html
automatic, shut down. (relay and EFI logic)
key point, the ASD will kill the engine, if fit sees spark is bad.
so its a chicken and egg deal.
here is the logic.
key on , crank , ASD closes, fuel injects and engine starts
then dies in seconds. or runs full time.
note that if the ECU sees spark dead, it cuts spark.
Sounds odd , huh. but is NOT.
this relay stops all car fires. (caused by this protection not in place)
ps: good luck finding it with no scan tool.... near impossibe. as it does throw codes. you will never see.
4.0L straight 6 4x4 done the tune up as well spark plugs, wires, distributor cap, rotor button, pick-up module the filters done it all because it used to cut off while driving but that was fixed with the crankshaft postion sensorit started after the crankshaft sensor was replaced it sounds like its my drive shaft ive been hearing like a ticking noise under it so i bought a u joint but still not sure thats the problem but i will check the asd relay as well it has probably close to 300,000 miles on it the speedometer doesnt work
just thought i would add the jerking solution was the ethanol in the gas whenever it would go through the injectors it would **** so started using non-ethanol gas and it has stopped jerking
×
SOURCE: serpintine belt
This link will take you to a picture of the diagram. If the link doesn't work contact me and I can email you the picture directly.
http://autorepair.about.com/library/illustrations/bl506a-lib.htm
SOURCE: change a serpentine belt on 04 jeep grand cherokee laredo
Check this link & scroll down to your engine. Click on picture to expand.
http://www.autozone.com/shopping/repairGuide.htm?pageId=0900c1528004328a
SOURCE: location of crankshaft position sensor Jeep grand cherokee 1997
left rear of engine block,on transmission bell housing.best way from top under brake booster use a wrench,
SOURCE: crankshaft sensor located 98 jeep grnd cher 4wd 6cy
it is located at the back of the engine on top of the transmission bell housing,the plug runs over to the passenger side of the engine bay and it comes out from behind the engine,you can actually get your hand on the sensor itself from under the hood on the drivers side,and i believe its a 13mm bolt holding it in,the new sensor will have a sticker on the end of it...leave it there,it is used for correct spacing between the sensor and the flywheel,hope this helps
Testimonial: "Everything was just like you said but as a not atleast for my jeep it is an 11mm not 13mm. Works great so far (keep fingers crossed) "
SOURCE: where is the crankshaft position
The Crankshaft Position Sensor (CKP) is mounted to the transmission bellhousing at the left/rear side of the engine block...
Inatallation: 4.0L Engine
New replacement sensors will be equipped with a
paper spacer glued to bottom of sensor. If installing (returning) a
used sensor to vehicle, a new paper spacer must be installed to bottom
of sensor. This spacer will be ground off the first time engine is
started. If spacer is not used, sensor will be broken the first time
engine is started.
New Sensors:
Be sure paper spacer is installed to bottom of sensor. If not, obtain spacer PN05252229.
Used Sensors:
Clean bottom of sensor and install spacer PN05252229.
Hope helps (remember to rate and comment this free answer).
587 views
Usually answered in minutes!
4.0L straight 6 4x4 done the tune up as well spark plugs, wires, distributor cap, rotor button, pick-up module the filters done it all because it used to cut off while driving but that was fixed with the crankshaft postion sensorit started after the crankshaft sensor was replaced it sounds like its my drive shaft ive been hearing like a ticking noise under it so i bought a u joint but still not sure thats the problem but i will check the asd relay as well it has probably close to 300,000 miles on it the speedometer doesnt work
The word jerk, has may meanings, it can be , stalls, misfire, or drive line, slack (u-joints) any mechanic can drive it for 5min and tell you which it is.
its the injectors got it fixed thanks for the help though
×