Another E4OD flashing OD light thread

94NAIDI

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I am not familiar with the RPM sensor wires. But I am eager to look. My truck does have a tachometer and that does work. If that tells us anything. But if tell me where those wires are, I’ll give them a thorough inspection when I return.
 

trackspeeder

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Ok. I decided to drive it to the airport so I could pull the codes. The OD light started flashing about 30 minutes into the drive. I pull over to read the codes. Hook up my scan tool, OD light still flashing. As soon as the scan tool starts the test (getting cylinder ID) the OD light stops flashing. I continue on with the test. Results 011 system passed. I disconnect everything and start back out on the road. OD light starts to flash again within a couple miles. I pull over again. Connect scan tool, same result. Get back on the road and the OD light remains flashing for the next 30 minutes of the drive. It was all interstate so I didn’t get a chance to notice any shifting issues. But I was obviously in limp mode. I’m sure it would have had a hard shift condition if not on the interstate.

By the time I get into town, the light goes off and everything seemed to be shifting fine. No limp mode.

It wasn’t until I get to the airport parking lot that I notice anything unusual. Cruising around 5 mph in parking lot the truck was surging like the torque converter was locking up instead of slipping. Kinda like letting off the clutch on a standard shift truck at to low of rpm. The truck would surge forward then release.

I don’t know if that was from driving in limp mode so long or if this is a symptom of what’s wrong.
Low fluid or low fluid pressure will lock the converter at low speeds. Check the fluid level.

Check the alternator, your issues are sounding like an electrical problem.
 

Greenie

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I am not familiar with the RPM sensor wires. But I am eager to look. My truck does have a tachometer and that does work. If that tells us anything. But if tell me where those wires are, I’ll give them a thorough inspection when I return.
Right up front, center of engine. Two black wires that connect the sensor sometimes lose insulation and make contact... Sometimes the sensor is bad. Not sure how to test it when it mostly works.
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94NAIDI

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I did check fluid when I did the fluid an filter change. I’ll look at all the other suggestions as soon as I get back from Texas.
 

94NAIDI

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Just got back from Texas. Of course the truck went into limp mode on my way back from the airport. First stop sign, I manually shifted it into first and manually sgifted through second to drive. OD light stopped flashing and the granny magically fixed it self. Or do it seemed. Drive fine the rest of the trip. But did notice torque converter felt like it was locking up coming down my driveway when I got home. I’ll be checking all the above suggestions this week. Hopefully during my time off for the holidays I can get this sorted out. I’m going to try to pull the codes using the paper clip trick, check tranny fluid level again while warm and idling, check all grounds, even run a separate ground to the tranny, and checking the RPM sensor. I’ll let you know what my results are. If only I could get the codes, that would be key. Not sure why my reader doesn’t detect them.
 

Nero

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It may be the tcm is on its way out. If it wasn't because they're so expensive I'd say try swapping it out.
 

94NAIDI

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I think I was successful in pulling codes using the paperclip jumper and test light method I found in another thread. I believe what I got was code 23 followed by code 26. While e re searching these codes, I got confusing information. Can anyone on here help decipher if these codes have anything to do with my transmission issues?
 

94NAIDI

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I did research the 23 code. Apparently you have to hold the throttle open during the test. Since I was by myself, I didn’t do that. So that is most likely the cause for the 23 code. But what about that 26 code? I’m still unsure what that is.
 

XOLATEM

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With just a quick search on the internet...(my tech info is elsewhere)...looks to be a problem with the FIPL and the TOT...

I would look for a bad ground from engine and trans to chassis and Battery (-)

help decipher if these codes have anything to do with my transmission issues?
Most certainly they would...the TCM has to monitor engine load from the FIPL and transmission temperature with the TOT...

If it were me....I would go over the grounds and also the positive connections...by taking the cables loose you may wipe the codes...and then hook everything up and check what voltages you have at the FIPL from each wire to the sensor...and then try it again to see what comes up
 

94NAIDI

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The RPM sensor wires and connector in good shape?
Looking at the RPM sensor. The wires look good and the connector looks good. But there is what looks like possible oil fowling coming out from around the wires that enter the sensor itself. Not sure if it is normal to have oil on the sensor or not. This engine did just get redone with all new gaskets. So this would have been perfectly clean a month or so ago. It looks like maybe oil is seeping out of the back of the sensor. Is that normal?
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94NAIDI

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Just tested the FIPL. It was at 1.35 volts at closed idle position. So I adjusted it to 1.193 volts. That’s the closest I could get it to stay at. It now reads 1.193 volts at idle and 4.034 volts at wide open throttle. I read it should be 1.2 volts and 4.5 volts at wide open. Are my readings OK? I do have the grey FIPL in the truck. But no idea how long it’s been in there.
 

94NAIDI

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It’s 10 degrees here today. Is it possible the code 26 was because the tranny fluid is not up operating temperatures?
 

94NAIDI

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Rechecked fluid level. It is spot on. Cleaned both grounds from battery to engine. Found one ground from back of engine to body. Cleaned that one as well. I did not find any grounds from frame/body to tranny. So I ran a separate ground from battery to transmission. I just did this today, and since my issue is so intermittent, it’ll probably be a couple days before the problem pops back up. If it does at all.

I think I’ve done all suggestions this far.

Let me know if I should be concerned about that RPM sensor with some oil on the wire. Also let me know if my FIPL readings seem good. I don’t want to throw unnecessary money at it. But if those are worth replacing, I certainly will.

Fingers crossed something I’ve done will solve it.
 

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