1989AMCXJ
NAXJA Forum User
- Location
- Big Bear Lake
I have read countless articles on this issue, and I have found zero solutions. Any guidance here would be gratefully appreciated. OK, Starts cold no problem, drive it up to normal operating temperature, park it for 25 minutes or more, No start, just crank...Let it sit for hours, until cold again, starts.
Engine: Renix L6 4.0 with Cam, Polished ported head, bored out throttle body to HO specs, TB spacer, pacesetter headers.
Fuel New: Fuel Pump assy and pump, hoses, FPR, 3rd Gen Bosch four hole injectors, Insulation on manifold, fuel rail and injectors. Fuel Pressure 35lbs. Air fuel gauge reads Ideal to sometimes rich condition.
Sensors: ALL NEW including CPS. (tried to purchase better quality parts, not cheapy ebay china crap.)
Also Running the "R.E.M.+ V3" (hooked directly to the ECM port) and all diagnostics are within factory specs and no error codes out of range (Pre-OBD).
Ignition: Yellow top Bat good, Bosch High output Alt. Good, Cap, Rotor, Distributer (1 year old), Plugs, wires (1 year old), Coil, Coil Module, Starter relay switch, all other relays(4)(1 month old).
Grounding: Extra #4Cu gnd from rear of engine to Firewall and from bat gnd mount on block to second location on firewall, and from bat to gnd on front of frame.
(Positive cable from bat to starter good)
CPS Testing Results:
Cold Engine
Testing: CPS plug (Wiring harness end ignition on): 3.4V
CPS Resistance: 232
CPS AC V Spike when cranking: 0
Drove XJ, all warmed up, no issues. 180F
20 minute wait, test then crank: started up no issues
Engine Warmed up
Testing:
CPS plug (Wiring harness end ignition on): 3.4V
CPS Resistance: 278-280
CPS AC V Spike when cranking: 0
20 Minute wait, crank: started up no issues 160F
25 more Minutes wait, crank: 140F no start
CPS ohms test on harness side: 9.36
5 minutes later, started right up
Drove 10 miles, parked, came back hour later, no start, than I tried open throttle, started right up...
I am losing my mind!!! :looney:
Engine: Renix L6 4.0 with Cam, Polished ported head, bored out throttle body to HO specs, TB spacer, pacesetter headers.
Fuel New: Fuel Pump assy and pump, hoses, FPR, 3rd Gen Bosch four hole injectors, Insulation on manifold, fuel rail and injectors. Fuel Pressure 35lbs. Air fuel gauge reads Ideal to sometimes rich condition.
Sensors: ALL NEW including CPS. (tried to purchase better quality parts, not cheapy ebay china crap.)
Also Running the "R.E.M.+ V3" (hooked directly to the ECM port) and all diagnostics are within factory specs and no error codes out of range (Pre-OBD).
Ignition: Yellow top Bat good, Bosch High output Alt. Good, Cap, Rotor, Distributer (1 year old), Plugs, wires (1 year old), Coil, Coil Module, Starter relay switch, all other relays(4)(1 month old).
Grounding: Extra #4Cu gnd from rear of engine to Firewall and from bat gnd mount on block to second location on firewall, and from bat to gnd on front of frame.
(Positive cable from bat to starter good)
CPS Testing Results:
Cold Engine
Testing: CPS plug (Wiring harness end ignition on): 3.4V
CPS Resistance: 232
CPS AC V Spike when cranking: 0
Drove XJ, all warmed up, no issues. 180F
20 minute wait, test then crank: started up no issues
Engine Warmed up
Testing:
CPS plug (Wiring harness end ignition on): 3.4V
CPS Resistance: 278-280
CPS AC V Spike when cranking: 0
20 Minute wait, crank: started up no issues 160F
25 more Minutes wait, crank: 140F no start
CPS ohms test on harness side: 9.36
5 minutes later, started right up
Drove 10 miles, parked, came back hour later, no start, than I tried open throttle, started right up...
I am losing my mind!!! :looney: