Maryland Cherokee Club
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Year: 1998
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Year: 1999
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Includes alignments every 6 months or whenever you need one
Free tire rotation every 6 months or 6,000 miles
Free tire inspection and tire pressure check any time
Free maintenance inspection with your alignment
I got 4 alignments done when I was correcting my caster issue and looking for the perfect alignment so my Jeep wouldn't drift or wander on the highway at 75-85mph.
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Year: 1999
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I've been having a no start issue with my 99 Cherokee and am looking for advice. The originial CPS tested bad, so I replaced it (broke a bolt) and the Jeep ran for 2 days. Then it wouldn't start. I tested CPS and it failed. So I bought a new one and installed it but that is not the problem. I swapped the relays for fuel and ASD and verified the fuel pump is priming. I am getting no spark. I plan on testing the coil this week, anyone have any other ideas? Not sure how to check the harness going to the CPS.
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I've been having a no start issue with my 99 Cherokee and am looking for advice. The originial CPS tested bad, so I replaced it (broke a bolt) and the Jeep ran for 2 days. Then it wouldn't start. I tested CPS and it failed. So I bought a new one and installed it but that is not the problem. I swapped the relays for fuel and ASD and verified the fuel pump is priming. I am getting no spark. I plan on testing the coil this week, anyone have any other ideas? Not sure how to check the harness going to the CPS.
here's the test for the CPS harness:
http://www.jeepforum.com/forum/f11/c...5/#post8727201
Last edited by dukie564; 11-12-2013 at 02:08 PM.
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the coil is certainly prime suspect. It's also time you inspect the other sensor wiring also, particularly the o2 sensor - the wires have a knack for melting to the exhaust pipe and shorting all the sensors out.
here's the test for the CPS harness:
http://www.jeepforum.com/forum/f11/c...5/#post8727201
here's the test for the CPS harness:
http://www.jeepforum.com/forum/f11/c...5/#post8727201
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Year: 1999
Model: Cherokee
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the coil is certainly prime suspect. It's also time you inspect the other sensor wiring also, particularly the o2 sensor - the wires have a knack for melting to the exhaust pipe and shorting all the sensors out.
here's the test for the CPS harness:
Diagnostic steps to confirm the CPS is the cause of your no-start
You should be able to verify a bad cps, by unplugging it, and turning the ignition key to on. If the voltage gauge and/or the fuel gauge now displays correctly, replace the CPS.
Unplugging and reconnecting the CPS sensor where it connect to the main harness near the back of the intake manifold usually resets the ECU and if the jeep fires right up after doing this you can bet that the CPS is faulty and needs to be replaced.
Exchange the fuel pump relay and the ASD relay with one of the other similar ones in the PDC to eliminate the relays as the cause of the no-start. Confirm that the fuel pump to runs for 3-5 seconds when you turn the ignition key to ON.
Eliminate the NSS as a cause of no start. Wiggle the shift lever at the same time you try to start. Put the transmission in Neutral and do the same. Do the reverse lights come on when the shifter is in Reverse?
Inspect the wires and wire connectors at the O2 sensors on the exhausts pipe. A short circuit from melted insulation or from broken O2 sensor wires can blow a fuse and the ECU/ECM will loose communication. Don’t get tunnel vision and assume the sensor is bad (unless it tests bad with a meter). Damaged wiring or a dirty connector can inhibit the signal from making it to the computer. Inspect/test/clean/repair wiring or connectors as necessary.
here's the test for the CPS harness:
Diagnostic steps to confirm the CPS is the cause of your no-start
You should be able to verify a bad cps, by unplugging it, and turning the ignition key to on. If the voltage gauge and/or the fuel gauge now displays correctly, replace the CPS.
Unplugging and reconnecting the CPS sensor where it connect to the main harness near the back of the intake manifold usually resets the ECU and if the jeep fires right up after doing this you can bet that the CPS is faulty and needs to be replaced.
Exchange the fuel pump relay and the ASD relay with one of the other similar ones in the PDC to eliminate the relays as the cause of the no-start. Confirm that the fuel pump to runs for 3-5 seconds when you turn the ignition key to ON.
Eliminate the NSS as a cause of no start. Wiggle the shift lever at the same time you try to start. Put the transmission in Neutral and do the same. Do the reverse lights come on when the shifter is in Reverse?
Inspect the wires and wire connectors at the O2 sensors on the exhausts pipe. A short circuit from melted insulation or from broken O2 sensor wires can blow a fuse and the ECU/ECM will loose communication. Don’t get tunnel vision and assume the sensor is bad (unless it tests bad with a meter). Damaged wiring or a dirty connector can inhibit the signal from making it to the computer. Inspect/test/clean/repair wiring or connectors as necessary.
I used that test to verify the CPS itself is good but it doesn't show me how to test the actual harness or give me values that I should be reading to test the harness with a volt/ohm meter. The only thing from that list that I haven't done is check my O2 sensors.
I'll check out my coil and O2 sensors tonight, but if I don't see anything then I need to find a shop to diagnose this that knows something about Jeeps. I really don't want to take it to the dealership because they will just start swapping parts.
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Year: 1998
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Merchant's Tire in Glen Burnie has a 1 year alignment package for $139.99. Includes alignments every 6 months or whenever you need one Free tire rotation every 6 months or 6,000 miles Free tire inspection and tire pressure check any time Free maintenance inspection with your alignment I got 4 alignments done when I was correcting my caster issue and looking for the perfect alignment so my Jeep wouldn't drift or wander on the highway at 75-85mph.
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Year: 1999
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