Crank Sensor Mod for those with big hands
This can also be accomplished by using a software tool to re-program the CKPS and CPS offset. You can do it that way vs. elongating the holes in the bell housing. The problem with hole elongation is that it is not a very accurate way to time and, if they are not parallel, the sensor will sit ****-eyed in the hole vs. sitting perpendicular as it's supposed to. Too much of an offset leads to the rest of the EFI system being out of whack. The injector pulse width changes, the coil pulse changes etc.
How I go about getting to that sensor in the rear is to simply reach around the head or valve cover. I use a 3/8 in drive coupled to a U-joint. Once they are loose, remove both by hand.
Upon inserting the sensor, one needs to be aware of one thing and that is, when inserting this sensor into the rubber seal, those seals have a tendency of being pushed inside the bell housing. To prevent that from happening, apply a small amount of mineral oil to both sensor and seal. Do not apply oil to the face of the sensor. This makes sliding it in very easy. Remember to torque it to OEM spec. If it's not torqued down, it will come loose and start bobbling around which throws the timing way off.
As to the question regarding the face of the sensor being smooth or having grooves: A new one is smooth but, it is supposed to "settle in". This will leave two very slight depressions in the face of the sensor. Unless the sensor is not made to spec or, someone sold you the wrong one, the length is to be exactly the same as the OEM sensor so that the gap remains to OEM specs.
How I go about getting to that sensor in the rear is to simply reach around the head or valve cover. I use a 3/8 in drive coupled to a U-joint. Once they are loose, remove both by hand.
Upon inserting the sensor, one needs to be aware of one thing and that is, when inserting this sensor into the rubber seal, those seals have a tendency of being pushed inside the bell housing. To prevent that from happening, apply a small amount of mineral oil to both sensor and seal. Do not apply oil to the face of the sensor. This makes sliding it in very easy. Remember to torque it to OEM spec. If it's not torqued down, it will come loose and start bobbling around which throws the timing way off.
As to the question regarding the face of the sensor being smooth or having grooves: A new one is smooth but, it is supposed to "settle in". This will leave two very slight depressions in the face of the sensor. Unless the sensor is not made to spec or, someone sold you the wrong one, the length is to be exactly the same as the OEM sensor so that the gap remains to OEM specs.
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This mod seems to be a rather risky one pending who is doing this mod, could be an "ok" mod or one that could create alot of troubles to someone who is a little less mechanically advanced?? Guess unless someone who says that there is a real difference in power gains or mileage i can't justify doing this mod.
New to me here but, quick question: are the OBD I models NOT programmable?
I was talking to a guy with a Jeep today and he claims that more can be done with the older ones than the new ones as they allow more parameter changes vs. the newer ones where, there are fewer parameters that are adjustable. Whether that is true or not, I have no idea.
Last edited by cmckenna; Oct 29, 2009 at 01:33 AM. Reason: typo
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Thanks aimforsquirrels for answering my question and as for as my Ram being an OBD1 i am just fine with it. Spending the money on a aftermarket PCM isn't no worse then spending the money on a tuner, not that i really looked into the tuners either tho.. no need to for me. As far as everthing else is pretty much the same i believe?
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Well today I finally figured out a way to get at the crank position sensor to mod it. I have pretty big hands for a 6'1" guy, I've been able to palm a regulation size basketball since I was 14, (unfortunately, the height never caught up with the hands.) I've been struggling with this for a while, and I know a few others have too, so I thought I'd share with you how I finally got to it.
Anyway,I could just get my hand around the back of thepassenger side header, but I didn't have enough room to move it, (I wore gloves the first timeI tried and they got caught on the header bolts andI had my hand stuck for 10 min trying to undo the velcro strap on my mechanix gloves to free my hand.)[:@]
Today while looking at it, I noticed for the first time there was a heat shield directly behind the headerthat I could remove. I crawled under the truck and removed the heat shield bolts witha 1/4" drive socket wrench using a 7/16" deep well socket (need a deep well to get over the pointed bolts in the firewall). I couldn't get the heat shield out from under the exhuast so I just pushed it under the y pipe heat shield and ran it up over the top of the trannypan until it was far enough down and out of the way.
I disconnected the car battery as I didn't want to give myself an accidental jolt,then I wentback tothe engine bayon the passenger sidestanding on a 6" platform (2 of those greyBlitz Rhino wheel ramps pushed upperpendicular the passenger wheel)so I couldbend over thefender and back to thework areawithout standing on mytoes the whole time. I removed the round air filter so I could getover the valve cover, and threw a rag on the throttle body to keep debris out of the intake. Reached my right hand back there and could finally touch both crank sensor mounting bolts. The '01 has a 1/4" hex head hole in the top of both bolts, otherwise you'd need to use a 1/2"open end wrench. I broke thetwo bolts loose using the hex wrench the normal way (holding long end, short end in the hex hole).I then shoved my left hand just over the valve cover (under and aroundall the spark plug wires, ground wires, accessory vaccuum lines,heater hoses, etc.)just on the other side of the tranny dip stick and used that hand to flip the wrench over (long end in the hex hole) and guided it back into each hex hole. I used both hands to back the bolts out andpulled the crank sensor out of the rubber grommet and removed the rubber grommetfrom the bell housing.
Took about 10 mins toslot the bolt holes to 3/8" so the sensor would slide toward the oil filter using a handheld pigtail file. Cleaned it off with electric parts cleaner (it's a magnet and it grabbed a few filings), and placed it back in the bell housing. Replaced the easiest to reach bolt first and hand tightened it until it justheld the crank sensor in it's new place (slid toward the driver's side to advance the timing).ThenI threaded theharderbolt in place and tightened both down with the 1/4" hex wrench.Replaced the air hat and checked to make sure that I hadn't pulled any spark plug wires loose,climbed under the engine and replaced the heat shield, reconnected the batteryand cleaned up my tools.
Then I got in the truck and crossed my fingers. I have heard that the crank sensor is pretty fragile and Ihoped I hadn't damaged it.It ran slightly rough for about 20 secondsand I thought "Oh, crap" but it calmed down again and ran smoother than it had before the mod.
The whole ordeal lasted 2 1/2 hours,most of it trying to guide thehex wrench into the bolt holes blind. After Ifigured outa way to get the left hand in there, it went much faster.
I can't say that I noticed much of a performance gain, but I'm still getting used to the truck with the new gears, so there could be some, but not anything thatI really obviously noticed. One thing that I did noticewas that the truck seems to run smoother and for whatever reason (maybe psychological)it feels like I'm holding more power back when I'm on the brake at a stop,almost like the truck just wants to jump, but I don't have that feeling at cruising speed. I have heard thatmodding the crank sensorcan cause a truck to ping, but with the superchips I'mrunning premium gas anyway and it only calls for 91 octane, so there's probably a little head room left in there.
I know this is ratherlong-winded, but hopefully it'll help somebody out in the future, who has a similar problem to me.
Cheers! Tomorrow I'm going to flush the power steering system.
Anyway,I could just get my hand around the back of thepassenger side header, but I didn't have enough room to move it, (I wore gloves the first timeI tried and they got caught on the header bolts andI had my hand stuck for 10 min trying to undo the velcro strap on my mechanix gloves to free my hand.)[:@]
Today while looking at it, I noticed for the first time there was a heat shield directly behind the headerthat I could remove. I crawled under the truck and removed the heat shield bolts witha 1/4" drive socket wrench using a 7/16" deep well socket (need a deep well to get over the pointed bolts in the firewall). I couldn't get the heat shield out from under the exhuast so I just pushed it under the y pipe heat shield and ran it up over the top of the trannypan until it was far enough down and out of the way.
I disconnected the car battery as I didn't want to give myself an accidental jolt,then I wentback tothe engine bayon the passenger sidestanding on a 6" platform (2 of those greyBlitz Rhino wheel ramps pushed upperpendicular the passenger wheel)so I couldbend over thefender and back to thework areawithout standing on mytoes the whole time. I removed the round air filter so I could getover the valve cover, and threw a rag on the throttle body to keep debris out of the intake. Reached my right hand back there and could finally touch both crank sensor mounting bolts. The '01 has a 1/4" hex head hole in the top of both bolts, otherwise you'd need to use a 1/2"open end wrench. I broke thetwo bolts loose using the hex wrench the normal way (holding long end, short end in the hex hole).I then shoved my left hand just over the valve cover (under and aroundall the spark plug wires, ground wires, accessory vaccuum lines,heater hoses, etc.)just on the other side of the tranny dip stick and used that hand to flip the wrench over (long end in the hex hole) and guided it back into each hex hole. I used both hands to back the bolts out andpulled the crank sensor out of the rubber grommet and removed the rubber grommetfrom the bell housing.
Took about 10 mins toslot the bolt holes to 3/8" so the sensor would slide toward the oil filter using a handheld pigtail file. Cleaned it off with electric parts cleaner (it's a magnet and it grabbed a few filings), and placed it back in the bell housing. Replaced the easiest to reach bolt first and hand tightened it until it justheld the crank sensor in it's new place (slid toward the driver's side to advance the timing).ThenI threaded theharderbolt in place and tightened both down with the 1/4" hex wrench.Replaced the air hat and checked to make sure that I hadn't pulled any spark plug wires loose,climbed under the engine and replaced the heat shield, reconnected the batteryand cleaned up my tools.
Then I got in the truck and crossed my fingers. I have heard that the crank sensor is pretty fragile and Ihoped I hadn't damaged it.It ran slightly rough for about 20 secondsand I thought "Oh, crap" but it calmed down again and ran smoother than it had before the mod.
The whole ordeal lasted 2 1/2 hours,most of it trying to guide thehex wrench into the bolt holes blind. After Ifigured outa way to get the left hand in there, it went much faster.
I can't say that I noticed much of a performance gain, but I'm still getting used to the truck with the new gears, so there could be some, but not anything thatI really obviously noticed. One thing that I did noticewas that the truck seems to run smoother and for whatever reason (maybe psychological)it feels like I'm holding more power back when I'm on the brake at a stop,almost like the truck just wants to jump, but I don't have that feeling at cruising speed. I have heard thatmodding the crank sensorcan cause a truck to ping, but with the superchips I'mrunning premium gas anyway and it only calls for 91 octane, so there's probably a little head room left in there.
I know this is ratherlong-winded, but hopefully it'll help somebody out in the future, who has a similar problem to me.
Cheers! Tomorrow I'm going to flush the power steering system.
I'm a big boy and probably have bigger hands and forearms than most, but no matter what angle I try to attack this job I just can't get a feel for what I'm doing. I can't even see the sensor or the bolts, nor have I located where it's electrical plug is yet. I "think" I touched the rubber boot with my fingertips (horseshoe shaped, right?) but I couldn't feel the two bolts next to it. I have a 1996 so are these bolts hex head or recessed hex (allen)? Seems this should be more intuitive.
I was overjoyed when I found this thread thinking I would found the solution but squirrel's technique doesn't seem to work for me. Any advice to all that have gotten behind there? Also, anyone in the Maryland Eastern Shore area that know how to get a crankshaft position sensor changed out, there's a beer or two in it for your trouble if you can come over and help.