little help about O2 sensor and cooling sensor
#1
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Model: Cherokee
little help about O2 sensor and cooling sensor
I have a 1995, automatic, 4.0 4x4. I believe there's only one oxygen sensor in addition to the cooling sensor.
2-3 mechanics tell me that they both check out O.K. when the vehicle is connected to a computer. However, I get low mpg and.... weak idle irregularly and a consistent sense that my Jeep doesn't get a good air mixture (just my inexperienced opinion based on listening to an engine).
So, for about $75, I think it's worth replacing them both. This Jeep was not run daily in the past and was not well maintained. I'm pretty certain neither sensor has ever been replaced and I've driven this Jeep just after having a new set of spark plugs in it (no change in performance or feeling).
I don't know where these sensors are located and I'm on assuming that there are only the two of them.
Any links to info sites on my cherokee or any advice regarding my problem and the description above are appreciated.
2-3 mechanics tell me that they both check out O.K. when the vehicle is connected to a computer. However, I get low mpg and.... weak idle irregularly and a consistent sense that my Jeep doesn't get a good air mixture (just my inexperienced opinion based on listening to an engine).
So, for about $75, I think it's worth replacing them both. This Jeep was not run daily in the past and was not well maintained. I'm pretty certain neither sensor has ever been replaced and I've driven this Jeep just after having a new set of spark plugs in it (no change in performance or feeling).
I don't know where these sensors are located and I'm on assuming that there are only the two of them.
Any links to info sites on my cherokee or any advice regarding my problem and the description above are appreciated.
#2
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Year: 1987
Engine: Check
I have a 1995, automatic, 4.0 4x4. I believe there's only one oxygen sensor in addition to the cooling sensor.
2-3 mechanics tell me that they both check out O.K. when the vehicle is connected to a computer. However, I get low mpg and.... weak idle irregularly and a consistent sense that my Jeep doesn't get a good air mixture (just my inexperienced opinion based on listening to an engine).
So, for about $75, I think it's worth replacing them both. This Jeep was not run daily in the past and was not well maintained. I'm pretty certain neither sensor has ever been replaced and I've driven this Jeep just after having a new set of spark plugs in it (no change in performance or feeling).
I don't know where these sensors are located and I'm on assuming that there are only the two of them.
Any links to info sites on my cherokee or any advice regarding my problem and the description above are appreciated.
2-3 mechanics tell me that they both check out O.K. when the vehicle is connected to a computer. However, I get low mpg and.... weak idle irregularly and a consistent sense that my Jeep doesn't get a good air mixture (just my inexperienced opinion based on listening to an engine).
So, for about $75, I think it's worth replacing them both. This Jeep was not run daily in the past and was not well maintained. I'm pretty certain neither sensor has ever been replaced and I've driven this Jeep just after having a new set of spark plugs in it (no change in performance or feeling).
I don't know where these sensors are located and I'm on assuming that there are only the two of them.
Any links to info sites on my cherokee or any advice regarding my problem and the description above are appreciated.
Parts stores should have pics for you.
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Year: 1987
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Engine: 4.0 liter RENIX I-6, DIY Cold Air Intake, 2.5 FM Exhaust, 3 Core Radiator
MrPants, the desription of your symptoms sound more like a vacuum leak than a bad sensor, to me. The vacuum line going from the throttle body to the MAP sensor (on the fire wall behind the engine) is notorious for coming off or developing crack and leaking. Give all your vacuum lines a good looking over. Vacuum lines really dry out and crack often on rigs that are left sitting for a long time.
#4
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Year: 1987
Engine: Check
Good way to find a vacuum leak is to spray starting fluid on the vacuum hoses one at a time. If the engine rpms increase you found a leak.
Gotta have the motor running, btw...
Gotta have the motor running, btw...
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I have had the vacuum pressure checked twice.... the needle bounces a lot--but not too dramatically. I suppose mechanics could overlook something when doing a vacuum test???
#7
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Year: 1995
Model: Grand Cherokee
Engine: 4.0 with all of the noise and clatter
If the needle is bouncing on the vacuum gauge that means you have an intake valve that is not sealing, that would cause a crappy idle and fuel mileage.
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