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3rd gen 4.0 swapped into Renix detonation issue

POSrenix

NAXJA Forum User
Location
simi valley
I have a 88 renix that i have installed the 3rd gen 4.0 from a 2004 grand cherokee i used the H.O. head and the 99 up intake runs good i have an issue with detonation that i think re installing the Knock sensor will fix has anyone done this or do anyone have any opinions? !!!1
 
It just screws into the block. If it senses "hears" a ping/knock it will trigger the Renix ECU to retard the timing a few degrees. Ping is normally caused by running too lean. You may have some clogged injectors. I recommend running a can of BG44K through the fuel system to clean them. Remember that the signal from the knock sensor is high impedance and has to be run through a shielded cable to protect it from interference. The funny thing is that the interference will normally cause the timing to be retarded and reduce the probability of ping/knock. Unhooking the sensor normally will cause the timing to retard.

I would pull the plugs and do a reading. If you are not familiar with doing this, remove each one, label them, and post up the pix.
 
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currently it is unhooked so if i hook it up this will probably not help me with the detonation?as being not hooked up it is running retarded already
 
also the detonation is usaully when climbing a grade or when there is a slight load on motor which is to be expected to some extent ,im running the 99+ intake and throttle body from auto grand cherokee with neon injectors which all these non factory parts may be casing it to run lean?
 
also check for intake leaks, that can make lean running. spray aerosol flammable carb cleaner at the intake joints, vacuum hoses, injectors once motor is warmed up and idling steady. if upon spraying you get an rpm change, you found a leak.
 
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