My electrical problems are getting the better of me. I have a 93 grand Cherokee, with a 4.ltr. I narrowed my problem down to a “delay” issue. I’ll explain…
When I turn the key to start it’ll turn over until the check engine light comes on (30-60 seconds) before starting. If I wait 30-60 seconds with the key forward (but not to start) I hear a tick tick tick, at the power distribution fuse panel (under the hood), and the fuel pump pressurizes… the engine will now start. If I turn the engine off and try to start it right away it will start no problems!
I’ve used my multi-meter at the fuel pump, and it does not receive power until after the 30-60 wait, until the tick tick tick. That was leading me to believe the fuel pump relay was bad. I switched it and there has been no change.
I am thinking that I have a bad sensor somewhere and the wait is the PCM waiting for signal back from all the sensors, but one sensor is faulty and the PCM is by-passing to allow the engine to start after 30-60 seconds?? Am I crazy??
93’s are equipped with a OBD (on board diagnostics) I turn the key of and on three times and watch/count the number of times the check engine light flashes, then check the code. The only code that comes up is 12, (the power has been disconnected from the PCM in the last 50 ignition cycles)… I know this, I was the cause. So basically this is useless.
The only other symptoms are the extremely rough/low RPM idle. I’ve heard it many times that the crank positioning sensor is a common problem with these vehicles. I have removed it and cleaned it, but no change. I understand the this can be the cause for the rough idle since the CPS determines the fuel injection and ignition timing, but will this also cause my starting problem??
At this point I am going to replace my CPS and see what happens, but I’m not very optimistic at this point. I don’t want to end up replacing every GD sensor on the Jeep, I might as well go buy another vehicle… it may be cheaper!!
Any helpful feed back will greatly appreciated.
When I turn the key to start it’ll turn over until the check engine light comes on (30-60 seconds) before starting. If I wait 30-60 seconds with the key forward (but not to start) I hear a tick tick tick, at the power distribution fuse panel (under the hood), and the fuel pump pressurizes… the engine will now start. If I turn the engine off and try to start it right away it will start no problems!
I’ve used my multi-meter at the fuel pump, and it does not receive power until after the 30-60 wait, until the tick tick tick. That was leading me to believe the fuel pump relay was bad. I switched it and there has been no change.
I am thinking that I have a bad sensor somewhere and the wait is the PCM waiting for signal back from all the sensors, but one sensor is faulty and the PCM is by-passing to allow the engine to start after 30-60 seconds?? Am I crazy??
93’s are equipped with a OBD (on board diagnostics) I turn the key of and on three times and watch/count the number of times the check engine light flashes, then check the code. The only code that comes up is 12, (the power has been disconnected from the PCM in the last 50 ignition cycles)… I know this, I was the cause. So basically this is useless.
The only other symptoms are the extremely rough/low RPM idle. I’ve heard it many times that the crank positioning sensor is a common problem with these vehicles. I have removed it and cleaned it, but no change. I understand the this can be the cause for the rough idle since the CPS determines the fuel injection and ignition timing, but will this also cause my starting problem??
At this point I am going to replace my CPS and see what happens, but I’m not very optimistic at this point. I don’t want to end up replacing every GD sensor on the Jeep, I might as well go buy another vehicle… it may be cheaper!!
Any helpful feed back will greatly appreciated.
