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Loss of power

Dj0nes

By Dj0nes
in Engines & Drivetrain

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juf Enthusiast

juf

Posted
Posted

I haven't been to the dealer since I got the tune, so it should be good. Really seems like a bad sensor or something. It's like the computer is seeing something that isn't there and in turn causes the trans to shift poorly and the engine to not be as smooth. Almost like the throttle sensor is bad or something. It's a problem that is gonna take some digging and unfortunately my dealer is not willing to do that. So I'll probably just drive it until something breaks.

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TxTruckMan Senior Enthusiast

TxTruckMan

Posted
Posted

Could this be bad gas? Or a clogged fuel filter? DI engines run at a much higher fuel pressure, so a drop in pressure could cause something like this. Is fuel pressure monitored by the PCM to throw a code? Usually not. MAF problems usually throw a code as its performance is monitored.

14SLTZ71 Enthusiast

14SLTZ71

Posted
Posted

The weird thing is that when I noticed the loss of power my MPG went up from 15 to 18. I have been driving around for the last few days with traction control off and the loss of power seems to be gone and the MPG is back to 15.

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TxTruckMan Senior Enthusiast

TxTruckMan

Posted
Posted

Are you taling about when you floor the throttle and the tires spin? Because that will cause the traction control to cut the fuel to the engine to slow you down.

juf Enthusiast

juf

Posted
Posted

I also thought it could be fuel pressure related. There was a TSB out for it. I took it to the dealer and asked them to check fuel pressure. Was told "no codes" - their favorite line.

14SLTZ71 Enthusiast

14SLTZ71

Posted
Posted

Are you taling about when you floor the throttle and the tires spin? Because that will cause the traction control to cut the fuel to the engine to slow you down.

? Who said anything about flooring the throttle and spinning the tires

14SLTZ71 Enthusiast

14SLTZ71

Posted
Posted

I also thought it could be fuel pressure related. There was a TSB out for it. I took it to the dealer and asked them to check fuel pressure. Was told "no codes" - their favorite line.

I think it's AFM or fuel related. The problem is without a trouble code the dealership won't do anything.

Sometimes it stays in V4 and 6th gear too long and gets bogged down and then realizes "oh shit" I'm still in V4 and "damn" I should have down shifted.

14SLTZ71 Enthusiast

14SLTZ71

Posted
Posted

The weird thing is that when I noticed the loss of power my MPG went up from 15 to 18. I have been driving around for the last few days with traction control off and the loss of power seems to be gone and the MPG is back to 15.

Guess I spoke to quick, loss of power is back and traction control has no effect on it. I noticed that when I experience the loss of power I also get a whining noise when I let off the gas or slow down.

  • 3 weeks later...
14SLTZ71 Enthusiast

14SLTZ71

Posted
Posted

I have been noticing that sometimes my front rims get very hot and the backs stay fairly cool. Even on short drives. I was thinking that maybe the brakes weren't releasing all the way causing my loss of power.

 

Took it to 2 different dealership and was told that they couldn't duplicate it and that it's operating normal.

 

Well yesterday my check engine light came on and the front brakes locked up at a traffic light. I was barely able to get it to a parking lot, the front rims were soo hot you couldn't hold your hand on them, the backs were cold. I waited awhile and then was able to drive home.

 

Do your front rims get excessively hot and the backs stay fairly cool? Maybe this is causing the loss of power.

 

I have an appt tomorrow, hopefully they will find it.

patriot Enthusiast

patriot

Posted
Posted

I have been noticing that sometimes my front rims get very hot and the backs stay fairly cool. Even on short drives. I was thinking that maybe the brakes weren't releasing all the way causing my loss of power.

 

Took it to 2 different dealership and was told that they couldn't duplicate it and that it's operating normal.

 

Well yesterday my check engine light came on and the front brakes locked up at a traffic light. I was barely able to get it to a parking lot, the front rims were soo hot you couldn't hold your hand on them, the backs were cold. I waited awhile and then was able to drive home.

 

Do your front rims get excessively hot and the backs stay fairly cool? Maybe this is causing the loss of power.

 

I have an appt tomorrow, hopefully they will find it.

Yep, brakes are dragging.

14SLTZ71 Enthusiast

14SLTZ71

Posted
Posted

Yep, brakes are dragging.

Brakes were dragging, numerous fault codes, ABS, Traction control/stabiltrack, power brakes, power steering, etc.... At first they thought it was faulty wiring but that wasn't the case. They cleared the fault codes/check engine light and it seems to be gone. They told me to put some miles on it and if it doesn't return they still would like me provide feedback.

 

Definitely has more power now and front brakes are cooler, hopefully it doesn't come back.

14SLTZ71 Enthusiast

14SLTZ71

Posted
Posted

Yea, whatever, front brakes are dragging again, back to the dealer.

thewhitestallion Senior Enthusiast

thewhitestallion

Posted
Posted

that's crazy.... make sure whenever they fix the problem to replace your brake pads and rotors as the excessive heat from the brakes dragging more that likely put some heat spots in your rotors. at least now the problem is recognized and hopefully the problem will be solved and behind you. a faulty sensor is more than likely going to be the blame.

14SLTZ71 Enthusiast

14SLTZ71

Posted
Posted

that's crazy.... make sure whenever they fix the problem to replace your brake pads and rotors as the excessive heat from the brakes dragging more that likely put some heat spots in your rotors. at least now the problem is recognized and hopefully the problem will be solved and behind you. a faulty sensor is more than likely going to be the blame.

Yea, now the dealer tells me it's normal because none of the codes came back. Ok the code didn't come back but the condition is still there so how can that be normal.

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