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My only car, my TB is letting me down.

1470 Views 3 Replies 2 Participants Last post by  Blazernut
About a month ago, my TB had a dead battery, so I got it recharged. It then happened 2 more times. Finally, I bought a new battery. Don't know if it relates but, after that, I started getting the dreaded Reduced Engine Power Light along with the SES. Took it to Autozone and got code p1271 along with P0128. I found out p1271 could be APP sensor and P0128 is thermostat. I changed the thermostat and also bought a brand new APP sensor. Once I did that all the codes cleared, no lights no nothing.

Two weeks later, SES and REP comes back on, out of the blue. I then noticed that it turns on usually the first couple of times I turn on the car and go my way. After 3 to 6 times of stopping, turning off the engine and back on, the REP eventually does not turn on for the rest of the trip. SES does stay though. Also when the REP does turn on, it is usually when I let go the gas pedal or slow down.

I took it to Autozone today and now I have P1271 again but now I also have P1280.

I dont know what to do. I cannot afford dealership pricing right now and this is my only ride. I love my TB, but I am just afraid it will just completely shut off or eventually break something bigger. What should I do next, any suggestions?
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Hmmm I had to look at your profile to try to find the year and mileage of your truck. I see you omitted the year of your truck in your profile that is why none of your truck infor is showing at the top right of the header of the post. You can edit your info to fix that.

Some of the problems could be related to various sensor connections being dirty. However P1271 is the throttle position sensor :undecided and P1280 may go away when you fix that.
:m2:
Sorry about, got it fixed. Blazernut looks like you have the exact same TB as me. Have you experienced this problem at all? I already changed the APP sensor once and don't know where to next after this. Could anything with the clutch fan be related? I read several posts relating reduced engine power to that.
Sorry about, got it fixed. Blazernut looks like you have the exact same TB as me. Have you experienced this problem at all? I already changed the APP sensor once and don't know where to next after this. Could anything with the clutch fan be related? I read several posts relating reduced engine power to that.
The one thing about the fan clutch is the unmistakable roar that does not go away when it is locked up. (failed)

IIRC there are two related throttle position type sensors. One at the throttle body (is that the APP?) and one on the gas pedal (TPS?). If either one screws up you may experience that. The thing that points me in that direction is that you mentioned the relationship of you problems to the gas pedal positioning .... ie. coming off the throttle.:undecided

My truck runs very well and had not exhibited any lack of power until my thermostat failed in the usual way. When it fails it tends to over cool your system and not let the truck get up to the proper operating temperature. Kinda fools us old schoolers as we like to see things run cooler. I notice my temp gauge was a little under the midline and paid little attention to it. I did notice that my mileage and power were both diminishing and was kind of frustrated and thought I might blame my tune. :D As it turned out the thermostat was changed, operating temp was at the midline of the gauge and my power and fuel economy were increased dramatically! To the point that at WOT the wheels would break loose on the 1/2 shift in the rain. I have 3.42 gears.

Oy ya .... nice truck! :thumbsup:
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