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Lacation of knock sensor?

CW

NAXJA Forum User
I know its a dumb question but I pulled my '89 4.0 and don't remember taking it out. Is it located on the head or the block? My FSM says it's on the head in one section and block in another with no real description of location.
 
The factory knock sensor resembles an oxygen sensor, has a white barrel. On my 88 it is maybe 2 inches above the oil pan. It forward of the engine mount but not very much. The tip off is it uses the same connector as the fuel injectors. If recommend you install a new one since you have the engine out.

Guys says you can get them at NAPA but I had no luck. I paid around $70 for one at the dealer. The new one is a completely different design. They give you a stud to screw into the block then you place the doughnut shaped knock sensor on the stud, apply lock-tite to the threads and torque to 13 ft lbs.
 
:huh:

17? 89 inch pounds of torque is what my manual says. It also calls for teflon tape not lock-tight. Bad news is my $100 torque wrench didn't fit all that well because of the axle and track bar and everything else. The directions stated that torque was CRUCIAL to it's operation. I did my best and got to 89 and it seems to work fine. I bought it at NAPA which doesn't seem to stock it anymore. Here's one from Advance which is exactly the same as the one I bought from NAPA:

http://www.partsamerica.com/PartDet...nie&MfrPartNumber=AL1209&PartType=412&PTSet=A

FSM may be calling for the old part not the redesigned one. Maybe someone can clear this up for us.
 
Hawaii the "new design" knock sensor from chrysler has a different torque because of the different design. The first version looked like an oxygen sensor, the revised design was the doughnut which mounts on a stud.

IF you install the oxygen sensor type then use the value in the 88 EFI manual, but if you get the new style then follow the directions included in the package. The instrutions with the new design call out the lock-tite and new torque value.
 
Hi Martin,

I used the instructions that came with the sensor and with the manual. The link I posted is to the part which is the same manufacture and design as the one I installed.

Did your dealer part look the same as that one?
 
Yes it did. Who knows what going on we both can say we installed it the way they said in the package. I am not going to lose any sleep over it.
 
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