flashing o/d off light with a different twist

[gto4evr]

Hello,

sorry to bring this up in a seperate thread since I found tons of them in a search but here goes anyways.

Just today I got the truck back together after a month long fiasco changing the heater core and dropping the exhaust pipes to change all 4 o2 sensors and weld up a leak. This is a 98 Explorer 5.0 AWD. Truck started right up and I noticed the O/D OFF light flashing. CEL is not on and my code reader isn't pulling any codes out. This has never happened before this job previous to tearing out the dash/column/computer. Another worry is that during the exhaust R&R I took off the crossmember and jacked the tranny up into the floor boards to gain clearance to drop the pipes. Possible there's some magic sensor or something up there I broke? I didn't hear anything when I jacked it up to indicate crushing something. The truck seemed to shift fine when I drove it around the block. Now the truck also spent weeks with the front end jacked up about 8 inches higher than the back end if that would cause some kind of fluid movement that needs to settle or something. Any ideas? I had to pull half of the motor apart as well to get the heater tubes off, maybe something I'm missing when I put it back together and just can't see the hanging wire?

Any ideas would be GREATLY appreciated!

Thanks,
Dennis

 

[410Fortune]

your transmission wires are shared with your 3 ea 02 sensor wires....

First I would pull the code, when the OD light is flashing there is a code, if your code reader cannot get the code you need a different reader

Then I would check the wiring plugs on the pass and drivers side of the tranny, there should be 3 in 98 (range sensor, neautral sensor and pass side will have the 9 pin white plug for the internal shift solenoids and temp sensor)

Then pull the center console, seats and carpet back to get access to the floor panel for access to the 02 sensor and trans wiring.

the battery was disconnected when welding happened, correct?

pull your code, it will tell you what wires there is a problem with

 

[btimm86]

the code will probably go away if you flash your computer.

 

[gto4evr]

your transmission wires are shared with your 3 ea 02 sensor wires....

First I would pull the code, when the OD light is flashing there is a code, if your code reader cannot get the code you need a different reader

Then I would check the wiring plugs on the pass and drivers side of the tranny, there should be 3 in 98 (range sensor, neautral sensor and pass side will have the 9 pin white plug for the internal shift solenoids and temp sensor)

Then pull the center console, seats and carpet back to get access to the floor panel for access to the 02 sensor and trans wiring.

the battery was disconnected when welding happened, correct?

pull your code, it will tell you what wires there is a problem with

I got the sensors plugged in from underneath (boy THAT was fun) but there was a lot of tugging involved to pull it down far enough to depress the release tabs on the connectors. I didn't know about the access under the console til after it was done. I guess I'm pulling the console tonight to get at the top end. I can see the edges of the cover from underneath and it looks much bigger than the tiny little square opening in the rug I saw when the console was out during the heater core part of this job. I'm guessing I need to cut the carpet open to expose the whole cover for removal.

Pipes were completely off the car during the welding phase and the battery sat disconnected during the entire 4 weeks it took me to scrape enough time together to finish it. I pulled the battery after finding an open connector on the column I missed that lost me the column electrics. After plugging that back in, everything was fine except the o/d light so pulling the battery didn't clear the problem.

I put the call in to a friend at work who's got a $500 reader as opposed to my $20 special so hopefully he brings it in tomorrow so I can figure this out this weekend.

Thanks for pointing me to that top tranny wiring, I was about to pull open the dash again but the tranny/o2 sensor wiring bundle makes more sense.

I'll post up my findings tonight!

later,
Dennis

 

[410Fortune]

pulling on the 02 sensor wires = very likely source of your code

 

[btimm86]

disconnect your positive battery cable and turn on your headlights. then put the terminal back on and see if the code pops up again.

 

[410Fortune]

You dont have to turn on your headlights LOL

You can simply disconnect the negative battery cable for 5 seconds, OR you can pull teh EEC power fuse for 5 seconds, OR you can have your scanner clear all codes in memory.

If he jacked up his trans into the floor boards to gain access to the exhaust bolts and THEN pulled on the 3ea 02 sensor wires to get them unplugged and then fought and fought under the truck to plug them back in, I am going to say his problem is going to be in the very sensative wiring on top and on the sides of the transmission.

It is quicker and easier to get access through the floor to plug all this stuff in then it is to make love to your transmission to try and get the wiring plugged in IMO

 

[gto4evr]

You dont have to turn on your headlights LOL

You can simply disconnect the negative battery cable for 5 seconds, OR you can pull teh EEC power fuse for 5 seconds, OR you can have your scanner clear all codes in memory.

If he jacked up his trans into the floor boards to gain access to the exhaust bolts and THEN pulled on the 3ea 02 sensor wires to get them unplugged and then fought and fought under the truck to plug them back in, I am going to say his problem is going to be in the very sensative wiring on top and on the sides of the transmission.

It is quicker and easier to get access through the floor to plug all this stuff in then it is to make love to your transmission to try and get the wiring plugged in IMO

Bat's been pulled a few times during this and no go, I got the floor opened up last night (what fiasco, I live in rust land and two of the four J nuts snapped and spun, that was a LOT of fun getting them off!) anyways, I sure wish I would have done that in the first place since the connectors are all right up there. I jiggled wiring, plugged and unplugged all the connectors in on both sides of the tranny (though I didn't bother with that big one thats bolted together) and no dice. Still have the flashing light. Friend didn't come through with a super scanner that can pull the code. The CEL isn't on, just the O/D flashing and my scanner says no errors. Why the hell do they need to make this so difficult with having a seperate error code system for the tranny than the odb codes?! Is it possible that the cruise unit or something could affect this? I had most of the engine compartment connectors off as well since I had to pull half the motor off to get at the heater core intake tubes.

 

[410Fortune]

did you look inside the connectors?

The connector on the pass side of the trans (white 9 plug) MUST be seated fully and you need to make sure all the pins are in tact and in place

 

[gto4evr]

did you look inside the connectors?

The connector on the pass side of the trans (white 9 plug) MUST be seated fully and you need to make sure all the pins are in tact and in place

Never got that far. I went back at it after work for another round of connecter tugging and reseating. I popped the cruise unit wiring as I remembered seeing a green tinge to some of the leads when I looked inside it, brass brushed those, did a final wiggle to all of the wiring on top of the tranny, connected the battery and the light was OFF. ah sweet triumph! I was afraid counting my chickens so I kept checking after every step of reinstalling the console and after the test drive turning the O/D on and off, it's still fine.

Now I'm only back to my original problem I've had since I bought this truck a year ago: Truck starts immediately when cold. When it's hot and has sat for at least 15 minutes, it cranks for way too long and when it finally catches you can smell gas like it flooded to death. The only code I was pulling was a consistent 133 slow o2 response on bank one sensor one and an occasional P301 misfire in cylinder 1. I know I'm in the wrong forum for that but you guys are the only ones that bothered to respond to me! any ideas? Fuel pressure doesn't leak down, fuel pressure regulator tests out fine per the procedure and I've done a full tune up with new wires and plugs (and 4 fresh o2 sensors as well as a new MAF sensor) It seems to me the computer's trying to start too rich and it's flooding itself. Since I've got less than a mile on the truck since it's rebirth, no CEL so no codes, just the same symptoms it's had it's whole life I've had it. Any ideas?

And thanks again for the wiring tips!
Dennis