I recently was in need of replacing my MAT Sensor in my 89 YJ. However, this particular sensor has been discontinued by everyone including Chrysler and any OEM Part company as well.
Some of you may have been or still be in the same boat as I was earlier this month.
My car would not run right, idle rough, and this bad sensor would cause the engine to lobe and run poorly in the winter. Sometimes I wonder if this sensor was also causing my Jeep to run rich, but I'm not sure of this yet.
This MAT Sensor (Also known as an "Intake Air Temperature Sensor", or "Air Charge Temperature Sensor") was and still is nowhere to be found anymore.
The 87-90 has a pigtail with a weather pack plug on the end.
You'd think you could use the 91-95 model MAT Sensor, since it reads the same outputs electrically, but just doesn't have a pigtail. However, there is literally no way to securely plug the thing in to the 87-90 engine harness since the plug on the 91-95 model sensor is a completely different shape than your existing engine harness on 87-90 model Jeeps.
Que89yj let me know of a part that some companies such as "Wells" manufactures. It is an Intake Air Temperature Sensor for a different car (not exactly sure what car it is supposed to go in), that comes with a DETACHABLE PIGTAIL HARNESS, as well as the sensor itself, that you are supposed to crimp or solder on to your existing wire harness in your car.
I ordered one of these Intake Air Temp Sensors that come with the pigtail harness earlier last month, with both me and Que89yj, who has been working with me to fix my jeep from ground up, thinking it's all I need to replace my now inexistent MAT Sensor.
The part number is "SU113" and it is manufactured by Wells.
Here is a link to one of the sites that sells this sensor:
http://www.mypartsgarage.com/wells-intake-manifold-temperature-sensor-su113.html
When I got the part in the mail, thinking I'd have fixed yet another thing on my 1989 Jeep Wrangler YJ that I have slowly been restoring day by day, I tested everything to make sure it would fit before I did cutting and splicing to my 1989 YJ engine harness. I pulled the old MAT Sensor out of the intake manifold that came with the 1989 YJ (Most likely had been there since it was driven out of the dealership lot back in the late 80's... The thing was so old the tip of the sensor crumbled away in my hand when it came out of the intake itself) and compared the two, then tried to thread it into my intake manifold. The new sensor (Wells SU113) was about an eighth of an inch too wide of threads to even bolt into my exisiting 89 intake manifold!
I started thinking of what I could do to make it fit. The idea of tapping my intake was brought up, which I DID NOT WANT TO HAVE TO DO. Also the idea of using a die on the sensor was brought up, but I didn't want to get into using a die on it unless I absolutely had to.
After a while I found out that the 1991-95 Jeep YJ sensor (Wells SU343), looked a little bit thinner at the threads than the one I had purchased with the pigtail (Wells SU113), though, other than the thinner threads, looked the exact same.
The "Wells SU343" sensor that is compatible with 1991-95 Jeeps did not come with a pigtail, but had a plug or connector that looked exactly like the plug on the pigtail I purchased with "Wells SU113". I gave it a try and bought it online, not sure if I would have to return it or not.
Here's a link to a site that sells it:
http://autotechwarehouse.sophio.com/item.wws?sku=SU343&itempk=147827&mfr=WELLS&weight=0.50
When it was delivered to my door, I opened it up, tested everything to make sure the pigtail from Wells SU113 would fit the plug on the Wells SU343, and compared the thread size from SU113 to SU343 sensors. They were definitely smaller, but didn't know for sure if it would fit in an 87-90 intake manifold until I tried installing it.
Once again, I pulled the old 87-90 MAT Sensor out of my intake (The original that was old and destroyed pretty much), and started to thread the new 91-95 MAT Sensor into place.
To my surprise, everything fit air tight and perfectly! I cut the weather pack plug off of my engine harness since it was useless now since the original OEM 87-90 MAT Sensors that are able to plug into the original OEM 87-90 weatherpack plug on the engine harness are now extinct, and soldered/crimped the new pigtail from WELLS SU113 in its place.
**By the way, I did keep the old weatherpack plug from the original sensor connector on the engine harness, just in case of anything.**
I finally plugged the new WELLS SU343 sensor into the newly crimped and soldered pigtail off of Wells SU113, started the car and let it warm up. I tested everything as far as how it drives with a new working sensor in it. Everything seemed fine.
Finally, I tested the actual SU343 newly installed MAT Sensor with a multimeter. I forgot what the ohms were at exactly, but I guess it varies from the temperature the actual sensor is reading. According to the multimeter and the Chrysler service manual, the sensor works perfectly now.
The Jeep YJ now runs better, and more efficiently with a new sensor installed in it.
I know you have to buy two sensors to get a total of one replacement sensor to fit, but it is a lot better than running the car with a faulty MAT Sensor. Believe me, just driving it I can tell a difference.
Over the next few months I will be doing more walk throughs on my Jeep and how to fix things. Once I have 50 posts I will be adding a lot of pictures to what I do walk throughs on, but for now I just will send you links, doing the best I can to educate everyone.
I still have a lot to do on my 89 YJ, though it is running pretty good, there still is things wrong with it, and I want everything to be in tip top shape.
I will be doing these walk throughs as I go, so expect more informational threads by me.
Any questions just ask! Thanks guys
:cheers2:
Some of you may have been or still be in the same boat as I was earlier this month.
My car would not run right, idle rough, and this bad sensor would cause the engine to lobe and run poorly in the winter. Sometimes I wonder if this sensor was also causing my Jeep to run rich, but I'm not sure of this yet.
This MAT Sensor (Also known as an "Intake Air Temperature Sensor", or "Air Charge Temperature Sensor") was and still is nowhere to be found anymore.
The 87-90 has a pigtail with a weather pack plug on the end.
You'd think you could use the 91-95 model MAT Sensor, since it reads the same outputs electrically, but just doesn't have a pigtail. However, there is literally no way to securely plug the thing in to the 87-90 engine harness since the plug on the 91-95 model sensor is a completely different shape than your existing engine harness on 87-90 model Jeeps.
Que89yj let me know of a part that some companies such as "Wells" manufactures. It is an Intake Air Temperature Sensor for a different car (not exactly sure what car it is supposed to go in), that comes with a DETACHABLE PIGTAIL HARNESS, as well as the sensor itself, that you are supposed to crimp or solder on to your existing wire harness in your car.
I ordered one of these Intake Air Temp Sensors that come with the pigtail harness earlier last month, with both me and Que89yj, who has been working with me to fix my jeep from ground up, thinking it's all I need to replace my now inexistent MAT Sensor.
The part number is "SU113" and it is manufactured by Wells.
Here is a link to one of the sites that sells this sensor:
http://www.mypartsgarage.com/wells-intake-manifold-temperature-sensor-su113.html
When I got the part in the mail, thinking I'd have fixed yet another thing on my 1989 Jeep Wrangler YJ that I have slowly been restoring day by day, I tested everything to make sure it would fit before I did cutting and splicing to my 1989 YJ engine harness. I pulled the old MAT Sensor out of the intake manifold that came with the 1989 YJ (Most likely had been there since it was driven out of the dealership lot back in the late 80's... The thing was so old the tip of the sensor crumbled away in my hand when it came out of the intake itself) and compared the two, then tried to thread it into my intake manifold. The new sensor (Wells SU113) was about an eighth of an inch too wide of threads to even bolt into my exisiting 89 intake manifold!
I started thinking of what I could do to make it fit. The idea of tapping my intake was brought up, which I DID NOT WANT TO HAVE TO DO. Also the idea of using a die on the sensor was brought up, but I didn't want to get into using a die on it unless I absolutely had to.
After a while I found out that the 1991-95 Jeep YJ sensor (Wells SU343), looked a little bit thinner at the threads than the one I had purchased with the pigtail (Wells SU113), though, other than the thinner threads, looked the exact same.
The "Wells SU343" sensor that is compatible with 1991-95 Jeeps did not come with a pigtail, but had a plug or connector that looked exactly like the plug on the pigtail I purchased with "Wells SU113". I gave it a try and bought it online, not sure if I would have to return it or not.
Here's a link to a site that sells it:
http://autotechwarehouse.sophio.com/item.wws?sku=SU343&itempk=147827&mfr=WELLS&weight=0.50
When it was delivered to my door, I opened it up, tested everything to make sure the pigtail from Wells SU113 would fit the plug on the Wells SU343, and compared the thread size from SU113 to SU343 sensors. They were definitely smaller, but didn't know for sure if it would fit in an 87-90 intake manifold until I tried installing it.
Once again, I pulled the old 87-90 MAT Sensor out of my intake (The original that was old and destroyed pretty much), and started to thread the new 91-95 MAT Sensor into place.
To my surprise, everything fit air tight and perfectly! I cut the weather pack plug off of my engine harness since it was useless now since the original OEM 87-90 MAT Sensors that are able to plug into the original OEM 87-90 weatherpack plug on the engine harness are now extinct, and soldered/crimped the new pigtail from WELLS SU113 in its place.
**By the way, I did keep the old weatherpack plug from the original sensor connector on the engine harness, just in case of anything.**
I finally plugged the new WELLS SU343 sensor into the newly crimped and soldered pigtail off of Wells SU113, started the car and let it warm up. I tested everything as far as how it drives with a new working sensor in it. Everything seemed fine.
Finally, I tested the actual SU343 newly installed MAT Sensor with a multimeter. I forgot what the ohms were at exactly, but I guess it varies from the temperature the actual sensor is reading. According to the multimeter and the Chrysler service manual, the sensor works perfectly now.
The Jeep YJ now runs better, and more efficiently with a new sensor installed in it.
I know you have to buy two sensors to get a total of one replacement sensor to fit, but it is a lot better than running the car with a faulty MAT Sensor. Believe me, just driving it I can tell a difference.
Over the next few months I will be doing more walk throughs on my Jeep and how to fix things. Once I have 50 posts I will be adding a lot of pictures to what I do walk throughs on, but for now I just will send you links, doing the best I can to educate everyone.
I still have a lot to do on my 89 YJ, though it is running pretty good, there still is things wrong with it, and I want everything to be in tip top shape.
I will be doing these walk throughs as I go, so expect more informational threads by me.
Any questions just ask! Thanks guys
:cheers2:
