saburai
Explorer
Hi Gang,
We are on the road and ran in to a snag!
Here is the deal: 1999 XJ AX15 127,XXX miles. very well maintained, very good condition. Daily driver, frequent long distance high way driving.
Over the past year or so I've noticed, very infrequently (maybe 5-8 times total for both) two different symptoms.
1) A hard or "false" start. This would happen hot or cold. I turn the key, it seems to have started, but upon releasing the key it dies. Evey one of the 3-4 times this has happened, it started on the second try. I should add that it's starting is normally very quick and crisp, starting with very little effort.
2) Erratic idle and associated lack of throttle response. IIRC, this has only happened on a hot restart (i.e. coming out of a 7/11 to grab a quick snack.) This condition subsided, more or less after reving the engine in neutral. when this happened many months ago, I used a scan tool borrowed from an auto parts store to check codes and it did not throw any.
Yesterday, after going out for breakfast, we left the XJ parked and went for a hike for a few hours. Upon returning, it exhibited the "false start" described above. It did start normally on the second try. I did notice a gasoline smell just before pulling away. We returned to our friends house and parked. After dinner, I decided the we all needed some Ben & Jerry's so I hopped in the XJ and you guessed it, it wouldn't start. Dual AGM batteries plenty of cranking power. I tried 3-4 times waiting 10 minutes between attempts with no luck. I then checked for spark at both the coil and at a plug and also listened for the fuel pump. Pump sounded normal and I did have spark. It was late, so I gave up for the night and we used another car to get the ice cream... This morning, I went out to start checking in the daylight and I thought I'd try it again. It did the false start thing again and almost caught with a normal very short cranking cycle. I was initially thinking crank position sensor, but after searching, it seems that if I have fuel pump activation and spark that this would rule out the CPS. I will check fuel pressure if I can get my hands on a test gauge.
What are the other things that would cause this condition?
What to test and how?
I would add that I'm a experienced mechanic but this is my first Jeep and I've not worked on them before.
Please help me figure this out! We need to be back on the road on Thursday.
Many Thanks...
We are on the road and ran in to a snag!
Here is the deal: 1999 XJ AX15 127,XXX miles. very well maintained, very good condition. Daily driver, frequent long distance high way driving.
Over the past year or so I've noticed, very infrequently (maybe 5-8 times total for both) two different symptoms.
1) A hard or "false" start. This would happen hot or cold. I turn the key, it seems to have started, but upon releasing the key it dies. Evey one of the 3-4 times this has happened, it started on the second try. I should add that it's starting is normally very quick and crisp, starting with very little effort.
2) Erratic idle and associated lack of throttle response. IIRC, this has only happened on a hot restart (i.e. coming out of a 7/11 to grab a quick snack.) This condition subsided, more or less after reving the engine in neutral. when this happened many months ago, I used a scan tool borrowed from an auto parts store to check codes and it did not throw any.
Yesterday, after going out for breakfast, we left the XJ parked and went for a hike for a few hours. Upon returning, it exhibited the "false start" described above. It did start normally on the second try. I did notice a gasoline smell just before pulling away. We returned to our friends house and parked. After dinner, I decided the we all needed some Ben & Jerry's so I hopped in the XJ and you guessed it, it wouldn't start. Dual AGM batteries plenty of cranking power. I tried 3-4 times waiting 10 minutes between attempts with no luck. I then checked for spark at both the coil and at a plug and also listened for the fuel pump. Pump sounded normal and I did have spark. It was late, so I gave up for the night and we used another car to get the ice cream... This morning, I went out to start checking in the daylight and I thought I'd try it again. It did the false start thing again and almost caught with a normal very short cranking cycle. I was initially thinking crank position sensor, but after searching, it seems that if I have fuel pump activation and spark that this would rule out the CPS. I will check fuel pressure if I can get my hands on a test gauge.
What are the other things that would cause this condition?
What to test and how?
I would add that I'm a experienced mechanic but this is my first Jeep and I've not worked on them before.
Please help me figure this out! We need to be back on the road on Thursday.
Many Thanks...
