whitfimb
NAXJA Forum User
- Location
- Central Va
Friends Mom's 1989 Cherokee 4.0L auto 165k died.
Any help / advice / thoguhts would be greatly apreciated.
I picked it up with the trailer this evening (Saturday) and took it home. The Jeep will restart once cold (2-3 hrs). Upon restart it will cut off after 2-3 min. Once dead, turn off ignition and attempt to restart~ engine turns over but no start. Spraying the inlet with start fluid will make it run (Poorly but run) a few seconds and cut off, Looks at first glance to be a fuel issue.
I checked the fuel rail shrader valve. No PSI with key off (I thought it should hold some pressure with a check valve at the pump). Good stream / flow once key is flicked and pump is on / running. First guess is that the injectors are loosing signal once warm.
If I understand correctly their is a crank sensor and a (distributor mounted) cam sensor. Which one of these fires the injector signal?
I have found a few articles refering to issues with cam sensor timing... I'd like to check the sensor and the cam sensor timing. Anyone got a link to a good write up on the subject? Does it sound like a good direction to go?
My intensions are to return to her house Wednesday with a Noid light to check for injector signal and a Fuel PSI tester + My code scanner and volt/ohm meter. I'd like to look at the signal from the crank and cam sensor but have not invested in a new Ocilla Scope wave reading style tool yet, I'll try and see what I can see with the Volt Ohm meter.
I've had a few people say throw a crank position sensor on it (As that often fixes a no run) but I find it unusual for the sensor to break down once warm & restart cold. Hope to check it with the meter soon.
:read: searching and reading
Any help / advice / thoguhts would be greatly apreciated.
I picked it up with the trailer this evening (Saturday) and took it home. The Jeep will restart once cold (2-3 hrs). Upon restart it will cut off after 2-3 min. Once dead, turn off ignition and attempt to restart~ engine turns over but no start. Spraying the inlet with start fluid will make it run (Poorly but run) a few seconds and cut off, Looks at first glance to be a fuel issue.
I checked the fuel rail shrader valve. No PSI with key off (I thought it should hold some pressure with a check valve at the pump). Good stream / flow once key is flicked and pump is on / running. First guess is that the injectors are loosing signal once warm.
If I understand correctly their is a crank sensor and a (distributor mounted) cam sensor. Which one of these fires the injector signal?
I have found a few articles refering to issues with cam sensor timing... I'd like to check the sensor and the cam sensor timing. Anyone got a link to a good write up on the subject? Does it sound like a good direction to go?
My intensions are to return to her house Wednesday with a Noid light to check for injector signal and a Fuel PSI tester + My code scanner and volt/ohm meter. I'd like to look at the signal from the crank and cam sensor but have not invested in a new Ocilla Scope wave reading style tool yet, I'll try and see what I can see with the Volt Ohm meter.
I've had a few people say throw a crank position sensor on it (As that often fixes a no run) but I find it unusual for the sensor to break down once warm & restart cold. Hope to check it with the meter soon.
:read: searching and reading