help before i pay to have the help i need

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Nov 29, 2012
I have the following issues on my newly acquired 80. I bought it in Austin texas and drove it 8 hours to my home in Amarillo.

This is a 285,000 mile Land cruiser that i bought from the original owner. the engine light was on and when i did the diagnostic it shows the following. 28 which shows to be a o2 sensor. help here to replace it. then it had the following 83, 84, 85. from the research on here it seems as though i may need to replace the ecm to get the light to go out. The engine ran fine all the way home, but the truck was very sluggish starting off from a dead stop and i noticed at highway speeds that the overdrive light blinked off and on when it was in the on position. if i replace the ecm will this fix the problem that the codes show.

i have already changed out the transmission fluid and filter and the problem with the transmission still exist. i have not yet changed out the fuel filter that i have purchased so if this problem may be fuel related then i can replace that first.
What year is your cruiser? Did you replace both O2 sensors? Do you have a code reader (OBDII?) or are you getting codes with jumpering the diagnostic port?
2-digit codes indicates OBDI. He has a '93 or '94.

83, 84, 85 are transmission control module (TCM) open circuit. Specifically the link between the transmission control unit and the engine control unit is not reliably connected. This all goes through harness IH1 which is entirely inside the vehicle and goes from behind the driver's kick panel to behind the glovebox.

Make sure that the TCM cables are all plugged in all the way. Which is to say un-plug and re-plug. Go to radioshack and get some deoxit, spray the contacts. un-plug and re-plug a few times.

The TCM is under the driver's side kick panel. It's a box that says transmission control module on it.

Don't fear the wires. The wires are your route to salvation.
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But we've discussed this already, haven't we?

Changing trans fluid and filter won't connect a loose wire.

Here's how to read trouble codes from the TCM. I won't be surprised if this doesn't work, since you probably have a loose or dirty cable that you need to pull out, clean, and shove back in.

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1993 and I just used the jumper wire. can you tell me where the two o2 sensors are
Forget the o2 sensors. They are in front of the cats just past the passenger side wheel well, fwiw.

The codes you are throwing mean that the engine controller isn't reliably talking to the transmission controller.

It's as though you have a light switch that doesn't work so you are servicing a water faucet.
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83-84-85 is a known issue with the early engine ECUs, 89661-60170 and 89661-60220. The fix is to replace the ECU with an 89661-60221 which is no longer available new. You would need to locate a used one from a 6-93 to 12-94 wreck.

The "sluggish" part could be shift solenoids. Not unheard of in a 442.

After that there could still be more issues with a truck with close to 300 k on it.
There are several 89661-60221 on ebay, as low as $110 for an allegedly working part. You could also hit up people parting out trucks here.

And then there is who wants $200, etc.

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