Ponder this------Damn Dodge

[Wildman1]

So about a month ago I took my son up to Little Naches for a day of 4wheeling. It was his first ever REAL 4wheeling trip and his first trip out in his new Scout that he had bought. Of course everyone thought I would end up towing him back into camp. Well of course things don't normally end up as planned.

We went up to Ravens Roost or attempted too. We went on the upper part of the Powerline trail. We spent most of the day clearing downed trees as we were the first to go thru for the year. I ran out of fuel in my chainsaw so we turned around and headed back down the trail. Well we came to a large mud hole that I had seen guys play in a few years (10) ago. Being the big tough Jeep guy I figured no problem I'd make it thru no problem.

Those are 38" tires gone into the mud.

We stopped once we got to the road again to air his tires up and mine. The Jeep ran fine all this time and continued to run until I got to the T at Hwy 410. Just as I pulled onto Hwy 410 I lost all power and the Jeep died. So I towed the Jeep home and have been messing with it ever since. So far I have pulled the fuel tank to see if the pump was clogged, cleaned the pickup and tested the fuel pump. Reinstalled the fuel tank but still no start. I also have 40+ PSI to the engine fuel rail.

Of course my OBD II scanner stopped working at the same time as all this. So next I have clean as much of the under carriage as I can to try and see if there is a problem there. I can't find anything. I have replaced the crank position sensor and also have tested the throttle position sensor and still no fix. Right before I left for the PNW4WDA Trail Jamboree I tried to dump a little fuel down the throttle body and still no start. So during the week I was up camping with NO JEEP to drive I pondered that it might be a spark issue??
So got home and checked the spark, It's got some!! Just to make sure my ignition system was ok I did a tune up on it. Replaced the dist cap, rotor, & spark plugs. Also did a compression test while I had the plugs out.

So the Jeep will start and run at an idle but not all that well. It will die the minute you try to give it any gas. Once you have started it and it dies it will then not start again.

So throw some ideas out there guys--(Please other than get rid of the Jeep)

 

[crash2]

Without seeing the data its going to be hard to tell rick...

 

[Wildman1]

I guess I forgot a little more info.

The engine is from a 1998 Dodge Dakota. It is a 5.2L V-8

Yes Mike your right with out a scan tool to give some code or show what sensor isn't working it is pretty much a crap shoot. I was just looking for any ideas. I plan on taking the Jeep into the dealer or a local repair shop and have them test it for me. Then I'll just tow it home and fix it.

 

[zukkev]

So about a month ago I took my son up to Little Naches for a day of 4wheeling. It was his first ever REAL 4wheeling trip and his first trip out in his new Scout that he had bought. Of course everyone thought I would end up towing him back into camp. Well of course things don't normally end up as planned.

We went up to Ravens Roost or attempted too. We went on the upper part of the Powerline trail. We spent most of the day clearing downed trees as we were the first to go thru for the year. I ran out of fuel in my chainsaw so we turned around and headed back down the trail. Well we came to a large mud hole that I had seen guys play in a few years (10) ago. Being the big tough Jeep guy I figured no problem I'd make it thru no problem.

Those are 38" tires gone into the mud.

We stopped once we got to the road again to air his tires up and mine. The Jeep ran fine all this time and continued to run until I got to the T at Hwy 410. Just as I pulled onto Hwy 410 I lost all power and the Jeep died. So I towed the Jeep home and have been messing with it ever since. So far I have pulled the fuel tank to see if the pump was clogged, cleaned the pickup and tested the fuel pump. Reinstalled the fuel tank but still no start. I also have 40+ PSI to the engine fuel rail.

Of course my OBD II scanner stopped working at the same time as all this. So next I have clean as much of the under carriage as I can to try and see if there is a problem there. I can't find anything. I have replaced the crank position sensor and also have tested the throttle position sensor and still no fix. Right before I left for the PNW4WDA Trail Jamboree I tried to dump a little fuel down the throttle body and still no start. So during the week I was up camping with NO JEEP to drive I pondered that it might be a spark issue??
So got home and checked the spark, It's got some!! Just to make sure my ignition system was ok I did a tune up on it. Replaced the dist cap, rotor, & spark plugs. Also did a compression test while I had the plugs out.

So the Jeep will start and run at an idle but not all that well. It will die the minute you try to give it any gas. Once you have started it and it dies it will then not start again.

So throw some ideas out there guys--(Please other than get rid of the Jeep)

Hey Rick, Did you doublecheck that the tone ring for the CKP sensor is not packed with gunk??? Didn't realize (or maybe you told me and it slipped my mind!) you'd run thru that deep of mud hole!

 

[superglock]

The plugs look black, Could it be a water temp senser? I had a surbaban someone brought up and it ran fine two hours later I tried to move it and it wouldnt run, The temp sensor had it way to rick because it thought it was -40 degrees.

 

[CHOP SHOP]

Plugged cat.

 

[TreeClimber]

How old is the engine? Did it jump timing with the chain?

Did you break a wire to the O2 sender when you went into the mudhole?

(I think it could be the clogged cat too)

 

[Wildman1]

Engine had around 50,000 when it was pulled. It now has maybe 5-6,000 more miles since I installed it. A new exhaust was installed at that time. I had not thought about the Cat but it does make sense the way it is running.

 

[nevada]

Of course my OBD II scanner stopped working at the same time as all this.

are you talking the scanner itself? or the data port?

if its the port, than id say therein lies the problem.

 

[Wildman1]

No I am talking about the Scanner as I said before. Your right if the OBD II port was bad then your right, it would be an indication of a problem. One other thing I tried was replacing my ECU with a spare I have.

 

[Wildman1]

Chop Shop thanks for the idea. Yes it is the damn cat!! The exhaust is only 3 years old. I had it installed in June of 06. So I guess I'll replace it or maybe just gut this one. Now to figure out what clogged this one.

 

[PUO-BANNED]

From the looks of the plugs it's running too rich and the Cat cannot keep up. I bet if you cut the cat open it is plugged with carbon. dunking that hot cat in cold water was the last straw for it.

I'm with superglock on this one. the temp sensor is bad and it tricks the ecm into thinking that it's in cold start mode.

 

[TreeClimber]

From the looks of the plugs it's running too rich and the Cat cannot keep up. I bet if you cut the cat open it is plugged with carbon. dunking that hot cat in cold water was the last straw for it.

I'm with superglock on this one. the temp sensor is bad and it tricks the ecm into thinking that it's in cold start mode.

Any modern scanner should be able to give you live data feed from the OBD2 port. You can watch the temp sender as it comes up to operating temp.

What guages are you running with your conversion? And where does the guage get the feed? From the computer -or- from a seperate sender on the engine? On my TJ with a Chev motor, I had to install an entire guage cluster to make it work.

 

[TreeClimber]

Engine had around 50,000 when it was pulled. It now has maybe 5-6,000 more miles since I installed it. A new exhaust was installed at that time. I had not thought about the Cat but it does make sense the way it is running.

Chop Shop thanks for the idea. Yes it is the damn cat!! The exhaust is only 3 years old. I had it installed in June of 06. So I guess I'll replace it or maybe just gut this one. Now to figure out what clogged this one.

5-6000 miles in 3 years of operation will not clog a cat unless you have a substantial issue somewhere else. I wouldn't gut this one, as those residual problem still exists. Also, you may have an emissions test at some time, and this prevents future hickups.

When you borrowed the pickup motor, did you also get the trans? (because I don't know), did the trans have a speed sensor or some other related component that perhaps your computer needs to use to correctly calculate the air/fuel mix?

 

[Wildman1]

Any modern scanner should be able to give you live data feed from the OBD2 port. You can watch the temp sender as it comes up to operating temp.

What guages are you running with your conversion? And where does the guage get the feed? From the computer -or- from a seperate sender on the engine? On my TJ with a Chev motor, I had to install an entire guage cluster to make it work.

I am running the stock gauges with my swap. This was one of the reasons for me sticking with a Mopar engine. If you blend the two wiring harnesses using the truck and TJ harness the truck computer fits right where the Jeep computer was.

Before my scanner took it's crap on me the Temp Sensor was working.

5-6000 miles in 3 years of operation will not clog a cat unless you have a substantial issue somewhere else. I wouldn't gut this one, as those residual problem still exists. Also, you may have an emissions test at some time, and this prevents future hickups.

When you borrowed the pickup motor, did you also get the trans? (because I don't know), did the trans have a speed sensor or some other related component that perhaps your computer needs to use to correctly calculate the air/fuel mix?

I am using a pulse type speed sensor with the STaKs box. And then a Tru-Speed from Superlift to set my correct speed. I have a 44RE transmission to go with the engine.

I have thought about just running a straight pipe for a while. I am just wondering if I replace the Cat with a new one how long before this new one is toast?? I will have to get the Jeep into a shop and figure out what is going on.

 

[TreeClimber]

I am just wondering if I replace the Cat with a new one how long before this new one is toast??

If history is any indication, you've got about 3 years, and 5 or 6 thousand miles. :haha: Sorry. Somebody had to type it.:kiss:

Rumor has it my old Ford pickup had a straight pipe on it when it got sold, but I'm not certain. :redneck:

 

[TreeClimber]

I
Before my scanner took it's crap on me the Temp Sensor was working.

If you guage cluster is working, then your temp sender should also be ok. The TJ cluster gets it's signals from the computer (if I recall correctly), not the engine itself. Ergo, it the guage says you're at operating temp, then the computer should be correctly leaning/enriching the fuel mix.

[In my application, I installed a GM motor, which the Chrysler computer was unable to understand, thereby effectively dis-ableing my guages. This in turn forced me to install an all new guage cluster. For this reason I believed your guages are accurately reflecting your temp sender, and the temp sender is probably not the issue]

 

[CHOP SHOP]

Chop Shop thanks for the idea. Yes it is the damn cat!! The exhaust is only 3 years old. I had it installed in June of 06. So I guess I'll replace it or maybe just gut this one. Now to figure out what clogged this one.

Just gut that bitch and run it. My dad has a 96 dodge truck with that motor in it. He has duals and no cats. It runs fine, its been that way since 8,000 miles, it now has over 100K on it.

We live in the woods and dismantle EPA ****. Thats what rednecks do, besides burn tires.:redneck:

If it still runs rich, get a better intake/filter:haha:

I just think the cold water and mud killed it prematurely. Replacement CATs are very low quility these days. It just got pissed and plugged up.:awesomework:

 

[Wildman1]

TreeClimber,
Yes on a Dodge/Jeep the insturment cluster gets it reading from computer. Now I have heard of some folks fooling the stock computer by using all the stock engine sensors. Then the only thing on the cluster that won't work is the Tach. But you already have your custom dash.

 

[TreeClimber]

TreeClimber,
Yes on a Dodge/Jeep the insturment cluster gets it reading from computer. Now I have heard of some folks fooling the stock computer by using all the stock engine sensors. Then the only thing on the cluster that won't work is the Tach. But you already have your custom dash.

Which means if you temp guage on the cluster is reading normal temps, then the sender on the motor is accurate.

BTW, I've got the factory Chrysler manual for a 97 TJ if you need something referenced. We used it for the wiring schematics when I rewired it over to a GM harness.