Last summer I had an emergency post about a weird vibrating sound under the dash, the Transmission Light flashing and the warning beeper sounding. At that time the transmission temp was OK, the fluid was OK and there were no code lights. I called Allison and they said it appeared to be just an electrical glitch so I kept on going to New Mexico. This problem kept occurring occasionally and on our trip last week to Kansas City became almost constant. I had to turn off the warning beeper to maintain my sanity.
I called FOT and got Mark Harvey. As usual Mark was very helpful and said he remembered that there was an oil pressure switch
back on the Detroit engine that occasionally had caused a similar problem. Mike Grimes in parts sent the new part out that day. I, yes I am actually allowed to crawl under the coach now, crawled under the coach and was ready to install the new part when I found a very loose wire on the old switch. I tightened up the wire and bingo, no more noise, warning tones or warning lights. I trust our trip to Arizona next week will prove the problem is now fixed.
THANKS MARK HARVEY!!!!
Kent,
Glad to hear that you are actually allowed to do that. I can imagine that it was getting on Peggy's nerves having to do stuff for you all the time. Tell her "THANK YOU"!!! for putting up with you during your recovery time. And glad to hear about the loose connection. Now you have a spare oil pressure switch, and you'll know what to do when the time comes.
Kent,
I had my DDEC oil pressure switch go out on my coach as well. The only such failure on my engine in the 10 years I've had it. I blame myself. I replaced all my V-belts and and after the break-in period where to you go back and retighten them I skipped the A/C compressor belt since the compressor wasn't working. It became so loose and floppy that it struck the oil pressure pressure housing (plastic) and wore into it. It didn't seem to penetrate into the guts of it but I blamed the failure on it. After reading your post it makes me think it was really just a bad sensor.
I had much different symptoms: intermittent engine shut down light, sometimes followed by an actual shut down. All the dash gauges read normal. I would get a transmission light but only after the engine was shutdown and the coach was still rolling to a stop. Fortunately this occurred on a lightly traveled interstate with an adequate shoulder. Once stopped I read the codes and check everything. I'd start up again, everything seemed fine and I would go for another 5 miles. Did this several times and the duration started to get shorter and shorter. Ultimately had it towed to a DD shop where they diagnosed it pretty quick.
Pat, thanks for recognizing my good fortune. Peggy is a Jewel and I tell her frequently how much I appreciate her. When all of this happened she became my nurse, the bus driver, water tank filler, tank dumper, mechanic and still a very good friend. I wouldn't trade her for anything. However, she is having trouble relinquishing the mother hen attitude but I understand. It just feels so good to be able to do something for myself. After crawling around under the coach, I actually had some back pain from sore muscles. It felt soooo good.
John, I am a wee bit confused. The switch I was having trouble with is pretty far away from any belts. It is just forward of the slobber tube on the lower part of the passenger side of the engine. Do you also have a 6V92, 350 hp DDEC?
Kent,
Mine is a bit different: rear radiator, 300 hp and from descriptions in the engine block heater posts it seems they re-arraged many of the accessories. I wouldn't be surprise if Foretravel moved the sensor to a different port on the block. Going to 350 hp required a larger transmission and more cooling. The side radiator was the only way to get more cooling and then that required adding a larger (or additional) hydraulic pump for the fans. My hydraulic pump is only used for power steering.
Kent,
I found you're posts on this subject and I'm having the same problem with the ATEC relays rattling at idle and also a code 32 and check transmission light on. I also checked with James Triana last week at FOT and he said it was the oil pressure switch and to test it with a jumper wire. I did this today and the rattling stopped but still have the code 32. Do you know the part number is for the spare you have? I should should be able to get one locally from the Detroit shop here. Also, is it easily removed or is a special tool like a spark plug remover or socket needed? There are no loose wires on it and I'm sure it is faulty. Any help would be greatly appreciated.
Jerry aka Murph