93 3.3 Grand Caravan

I still have a problem...

I had a problem where I'd be driving on the highway and all of a sudden the speedo would go to zero and then back to what ever speed it was at. The lights, radio, etc. all continued to work. When it went to zero and back you could feel the trans re-engaging. It acted as though it lost power for less than a second and then came back up. I purchased a new ecu unit from the junk yard, same numbers. The problem went away and I thought it was the ecu. Now, 5 months later, I had this happen again. It's intermittent, doesn't happen very often and leaves no codes. So -- it's tough to troubleshoot. If the crank sensor was failing, would it react this way ? I've replaced the relays, ASD and fuel pump. Anyone have any ideas or suggestions on where to start troubleshooting.

thanks, nick

Reply to
ncs
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From what you've written and if you only lose the speedometer and not any other display gauges, then I'd suspect the original problem was the OUTPUT SPEED SENSOR. Since the computer loses the output speed, it triggers the limp mode and shifts the transmission to second gear. When the sensor signal then comes back into range and operates correctly, the computer shifts back to the correct gear. When you lose signal completely there should be a fault code set. This is a 20 something dollar part and takes about 10 minutes to replace. Good luck.

Bob

Reply to
Bob Shuman

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