Reduced Power Mode
guumbah
12-18-2006, 11:46 AM
Here's what happened - ran into Target for about 30 minutes while my wife stayed with sleeping kids in truck. She had map lights and stereo on the whole time (the battery drain is important later in this story). Drove about 5 minutes down the freeway, suddenly truck has no acceleration, SES lights up, backfires a few times, and dies. I feel like I ran out of fuel, but at this point, no Low Fuel light has come on. Pull to the left (I was in the HOV lane) and turned on the hazards. Call AAA and wait. After about 25-35 minutes, the hazards start to slow down, and the map light is getting dim. Then CHP shows up, runs a traffic break, and pushes me to the right shoulder (whew!). However, due to the nearly dead battery, I have no gear lights, so I am actually in D and not N at this point (I panicked, so no lecture please about how to find Neutral by going back up against the Reverse lockout). Anyway, AAA shows up finally, drops in 2 gallons of fuel, and jumpstarts me. Now the Low Fuel light finally comes on, and the truck goes into Reduced Power Mode. For those who don't know what this is, the engine will "rest" each cylinder by skipping firing cycles. Allowing you to run very slowly if you lose massive amounts of coolant. So, I call a friend out to take the wife and kids in his car, since the tow can't. In the meantime, I shut the truck off while we wait. Restart it a couple of times, still goes Reduced Power. My friend shows up before the flatbed, and I go to show him the Reduced Power message, and that time (and every time since) the truck starts up just fine. Other than the SES light was still on, because I had not cleared the code yet. I checked the coolant, and it's fine, there's a little fuel in the oil, which is normal, according to the manual. I put gas in it, and it ran fine the rest of the way home. I even drove around the block a few times after I dropped the wife and kids at home. Starts fine every time now too, and the SES light is now off as of this morning.
My question is this - does anybody think the Reduced Power Mode kicked in because I was pushed while in Drive? Maybe some sensor got tricked into thinking the engine was running with no pressure in the cooling system, or something like that. I was almost due for an oil change, so that is no big deal. I'm hoping to just change the oil (and start filling up at 1/4 tank) and be done with this, but if anybody thinks this is indicative of some other problem, please chime in.
Thanks!
My question is this - does anybody think the Reduced Power Mode kicked in because I was pushed while in Drive? Maybe some sensor got tricked into thinking the engine was running with no pressure in the cooling system, or something like that. I was almost due for an oil change, so that is no big deal. I'm hoping to just change the oil (and start filling up at 1/4 tank) and be done with this, but if anybody thinks this is indicative of some other problem, please chime in.
Thanks!
silverado122775
12-19-2006, 04:22 PM
I would not trust the truck to be "all better". I did some looking into your symptom and found this.
"Diagnosed as throttle position sensor was bad"
My guess was that when you pushed the engine while in "drive", you were pushing the cranks to a different position than what the engine remembers it being and that caused the REP.
I would get a comp on it to see if it is still spitting out any codes.
"Diagnosed as throttle position sensor was bad"
My guess was that when you pushed the engine while in "drive", you were pushing the cranks to a different position than what the engine remembers it being and that caused the REP.
I would get a comp on it to see if it is still spitting out any codes.
guumbah
12-20-2006, 10:23 AM
That's basically what I'm thinking. The engine turning could have thrown off any number of sensors IMO. The 4Wheel Steer has acted funky as well, so ya, I don't think I'll trust it until I hook it up. I'm also a little worried about the jump maybe messing up something. The guy didn't see the giant red box hanging off the alternator for the + connection, so he kept monkeying with it on the battery post and making everything power up and down rapidly.
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