OBD Reader on Comanches

[Comanchakazie]

Hi everyone! I'm brand spankin' new to this forum, and just bought my first Comanche (first car actually), and was wondering if any of you use OBD readers to find any issues on your trucks, or how does one go about diagnosing issues? Forgive my ignorance.

[Tex06]

Google "how to retrieve codes OBD1 jeep" for the 91-92 models. The truck will tell you from a very limited code selection. The renix motors, I'm less sure on.

 

Other than that, do you have a specific issue? These aren't new cars that self diagnose, lol.

 

Sent from my SM-G930T using Tapatalk

[Comanchakazie]

Haha, yeah, I figured. But it had an obd, and I was wondering if it would work, so I can go purchase the reader. Specifically, I know it won't start. It cranks, but won't turnover. That was only recently. There is also a leak coming from the transmission and the rear end of the driveshaft, which I'm curious about. Also, it's a base 1990 4.0L

[87MJTIM]

Haha, yeah, I figured. But it had an obd, and I was wondering if it would work, so I can go purchase the reader. Specifically, I know it won't start. It cranks, but won't turnover. That was only recently. There is also a leak coming from the transmission and the rear end of the driveshaft, which I'm curious about. Also, it's a base 1990 4.0L

 

If you're a 90 then you are not OBD.  You have a Renix Jeep.  In order to read the codes from the ECU you need to get either a SnapOn MT2500 scanner with the Jeep card and adapter plug or search on Facebook or Youtube for "Nickintime."  He makes a Renix Engine Monitor (REM) the can read and display the codes in real time.

 

Unfortunately, for either of the above monitors to work with a Renix, the engine has to be running. :doh:   So, until you solve the first issue (getting it running) neither device will do you much good.

[G00SE]

Not meaning to"HighJack" nobody's thread, but what would cause a "Emiss Maint" light to be on my 1989 mj? And what is "Renix" ??

 

Sent from my LGLS990 using Tapatalk

[omega_rugal]

Not meaning to"HighJack" nobody's thread, but what would cause a "Emiss Maint" light to be on my 1989 mj? And what is "Renix" ??

 

"Emiss Maint" light comes when is time to change your O2 sensor, you must change the sensor and reset/get-a-new timer

 

Renix is brand/type of system that controls you engine...

[Eagle]

"Renix":

 

The ignition & injection system in the '86 through '90 Cherokee and Comanche was a product of a joint venture between Renault and Bendix. Thus ... RENault + bendIX.

[Jeep Driver]

Not meaning to"HighJack" nobody's thread, but what would cause a "Emiss Maint" light to be on my 1989 mj? And what is "Renix" ??

 

Sent from my LGLS990 using Tapatalk

Reach under the dash and unplug the timer.

[omega_rugal]

Reach under the dash and unplug the timer.

 

and...? change O2 sensor?

[G00SE]

What does "The Timer" look like and if when I change my oxygen sensor does "The Timer" reset itself or how will I reset it?

 

Sent from my LGLS990 using Tapatalk

[Jeep Driver]

 

Reach under the dash and unplug the timer.

 

and...? change O2 sensor?

 

It's a 30 year old plastic clock, I find it completely irrelevant.

[Jeep Driver]

What does "The Timer" look like and if when I change my oxygen sensor does "The Timer" reset itself or how will I reset it?

 

Sent from my LGLS990 using Tapatalk

Do what you need to do for your engine. 

 

The timer on an '88 is just to the right of the steering column at the front of the dash. 

Mine was a small white/transparent box. 

[G00SE]

Will the current oxygen sensor still work when "The Timer" is unplugged?

 

Sent from my LGLS990 using Tapatalk

[omega_rugal]

It's a 30 year old plastic clock, I find it completely irrelevant.

 

the box is irrelevant, you can also ignore the light and be done with it... or remove the bulb

 

what is not irrelevant is changing the sensor unless he wants the engine to drip gasoline all the time...

[Jeep Driver]

Will the current oxygen sensor still work when "The Timer" is unplugged?

 

Sent from my LGLS990 using Tapatalk

They are not related. 

 

 

For that matter, the clock could have quite 10 years ago 5 minutes before it sent a signal to the service light.........IOWs it could be telling you now what it should have told you 10 years ago. How would anyone know? you wouldn't. 

 

Ignore it. 

[Eagle]

What does "The Timer" look like and if when I change my oxygen sensor does "The Timer" reset itself or how will I reset it?

 

Sent from my LGLS990 using Tapatalk

The timer does not reset itself. The factory says they cannot be reset. Some people have figured out how to open them up and reset them, but most of us ignore it. The O2 sensor is supposed to be replaced every 80,000 miles. I just do it at multiples of 75,000 because that's easy to remember.

[HOrnbrod]

"Renix":

 

The ignition & injection system in the '86 through '90 Cherokee and Comanche was a product of a joint venture between Renault and Bendix. Thus ... RENault + bendIX.

 

A desperation marriage made in hell.  :rotfl2:

[Eagle]

 

"Renix":

 

The ignition & injection system in the '86 through '90 Cherokee and Comanche was a product of a joint venture between Renault and Bendix. Thus ... RENault + bendIX.

 

A desperation marriage made in hell.  :rotfl2:

 

 

You only tell yourself that because you can't admit that you secretly envy those of us with Renix MJs.

[HOrnbrod]

 

 

"Renix":

 

The ignition & injection system in the '86 through '90 Cherokee and Comanche was a product of a joint venture between Renault and Bendix. Thus ... RENault + bendIX.

 

A desperation marriage made in hell.  :rotfl2:

 

 

You only tell yourself that because you can't admit that you secretly envy those of us with Renix MJs.

 

 

We both be olde pharts my friend, but you have gone delusional already. 

[G00SE]

So, with 140+ on the odometer I'd guess it's probably past it's golden years in service...

 

Diagnosis:

a)Unplug "The Timer"

b)Replace Oxygen Sensor..

 

Thanks everybody

G00SE

 

Sent from my LGLS990 using Tapatalk

[Eagle]

So, with 140+ on the odometer I'd guess it's probably past it's golden years in service...

 

 

 

140,000 miles?

 

Barely getting broken in. The Jeep 4.0L engines are usually good for 250,000 to 300,000 with just routine oil changes and maintenance.

[G00SE]

 

So, with 140+ on the odometer I'd guess it's probably past it's golden years in service...

 

 

140,000 miles?

 

Barely getting broken in. The Jeep 4.0L engines are usually good for 250,000 to 300,000 with just routine oil changes and maintenance.

Wish I had taken pictures of the MJ when I dug it out of a Muskydime bush where it had been sitting for the past 5or6 years. The guys son had worked on the fuel injection and put 3 wrong injectors from something in it and didn't replace the orings on the fittings and the original owner just parked it after his son fixed it because it wouldn't run and it was leaking gas everywhere out of regulator side...

Now she purrs like a kitty cat

 

Sent from my LGLS990 using Tapatalk

[Eagle]

 

 

So, with 140+ on the odometer I'd guess it's probably past it's golden years in service...

 

140,000 miles?

 

Barely getting broken in. The Jeep 4.0L engines are usually good for 250,000 to 300,000 with just routine oil changes and maintenance.

Wish I had taken pictures of the MJ when I dug it out of a Muskydime bush where it had been sitting for the past 5or6 years. The guys son had worked on the fuel injection and put 3 wrong injectors from something in it and didn't replace the orings on the fittings and the original owner just parked it after his son fixed it because it wouldn't run and it was leaking gas everywhere out of regulator side...

Now she purrs like a kitty cat

 

 

 

I love it when kids "fix" things. Back in my Hudson collector days, the guy who owned the 5 & 10 cent store down the road (that should give you a hint how old I am) GAVE me his old Hudson, which was a twin to the one my grandfather once had, because his son had "fixed" the head gasket and it wouldn't run after that. Of course, his son had never heard of gasket compound, or a torque wrench. The guy obviously expected that I was going to have the car towed away. I wish I had a photo of his (and his son's) face when I pulled the head (very easy on a flathead six), gooped up the same gasket sonny had used, put it all back together, fired it up, and drove it home.

[fiatslug87]

Your no start may be a CPS (crankshaft position sensor) issue. You can try unplugging and plugging it back in. It's located at the top of the bellhousing on the driver's side, follow the wire to it's connection near the back of the valve cover. Search the forums for crankshaft position sensor, you'l get a lot of information. Good luck.

[cruiser54]

Your no start may be a CPS (crankshaft position sensor) issue. You can try unplugging and plugging it back in. It's located at the top of the bellhousing on the driver's side, follow the wire to it's connection near the back of the valve cover. Search the forums for crankshaft position sensor, you'l get a lot of information. Good luck.

and easy to test.

 

http://cruiser54.com/?p=50