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6.0 bogs at full throttle

Rocky Adams
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Rocky Adams Enthusiast

Rocky Adams

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I have an 07 2500 with a 6.0l.
i Recently bought a CTS3 edge tuner and installed it. When I tried to do a hot tune. It drops timing at full throttle. As soon as I let off a little bit on the throttle. It continues accelerating just fine.

 

it runs fine for the first 10mins on the tune. Then starts losing timing. 

I also have a knock sensor code on my check engine light. Guessing that has something to do with it?

I've searched this site high and low and can't seem to find anyone else having the same problem. 

The other issue may or may not be related to that problem, but this is also happening. When going up the slightest incline on the highway (overpass, for example) the engine bogs, it loses speed, and it has to kick down to a lower gear. It doesn't do it at slower speeds like 50-55mph. Up around 65-70 it is very bad. RPMs at 65 mph is around 1700.

CamGTP Senior Enthusiast

CamGTP

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Any knock sensor code will cause the computer to pull lots of timing, usually up to 8-10 degrees under heavy load. You can watch the knock channel if it has one to see how much it's pulling out.

 

The other problem is hard to say without seeing the truck or driving it. If it's a 6L90e transmission try pulling it down into manual mode in M5, see if it does the same thing once you get to higher speeds.

Rocky Adams Enthusiast

Rocky Adams

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18 minutes ago, Supreme Pizza said:

I would troubleshoot by bypassing the knock sensors (briefly) just to ensure that they are the problem.

 

If so, I would modify the fuel to prevent the fuel from triggering the knock sensors.

Thank you. 

CamGTP Senior Enthusiast

CamGTP

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You can't bypass them without an aftermarket tuner and bypassing them would mean turning the codes off permanently.

 

Knock sensor codes are circuit codes, so if you unplugged them to bypass them it would still turn the engine light on for both sensors.

 

 

 

 

Rocky Adams Enthusiast

Rocky Adams

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2 hours ago, CamGTP said:

Any knock sensor code will cause the computer to pull lots of timing, usually up to 8-10 degrees under heavy load. You can watch the knock channel if it has one to see how much it's pulling out.

 

The other problem is hard to say without seeing the truck or driving it. If it's a 6L90e transmission try pulling it down into manual mode in M5, see if it does the same thing once you get to higher speeds.

So it actually has the 4L80 in this truck. I guess it’s a 06 1/2 but it’s a cat eye

Rocky Adams Enthusiast

Rocky Adams

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2 minutes ago, CamGTP said:

You can't bypass them without an aftermarket tuner and bypassing them would mean turning the codes off permanently.

 

Knock sensor codes are circuit codes, so if you unplugged them to bypass them it would still turn the engine light on for both sensors.

 

 

 

 

So just replace the knock sensors and call it a day? Is it common to have wiring issues? Anything I should keep my eye out for while changing them out?

Rocky Adams Enthusiast

Rocky Adams

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25 minutes ago, Supreme Pizza said:

I would troubleshoot by bypassing the knock sensors (briefly) just to ensure that they are the problem.

 

If so, I would modify the fuel to prevent the fuel from triggering the knock sensors.

Would I need to pull fuel or add? 

Supreme Pizza Senior Enthusiast

Supreme Pizza

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1 minute ago, CamGTP said:

You can't bypass them without an aftermarket tuner and bypassing them would mean turning the codes off permanently.

 

Knock sensor codes are circuit codes, so if you unplugged them to bypass them it would still turn the engine light on for both sensors.

 

 

 

 

 

 

By "bypass", I mean remove them from the equation. There are several ways. You could unscrew them from the block and isolate them. Then ground them with gator clips. Or you could get some $10 eBay knock sensors, and plug them into the harness with the ground wires. Just remove them from the list of possible problems.

Rocky Adams Enthusiast

Rocky Adams

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1 minute ago, Supreme Pizza said:

 

 

By "bypass", I mean remove them from the equation. There are several ways. You could unscrew them from the block and isolate them. Then ground them with gator clips. Or you could get some $10 eBay knock sensors, and plug them into the harness with the ground wires. Just remove them from the list of possible problems.

bypass permanently? Or temporarily?


I have a extra set of OEM knock sensors. Would it be worth it to just try them and see?

Supreme Pizza Senior Enthusiast

Supreme Pizza

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1 minute ago, Rocky Adams said:

Would I need to pull fuel or add? 

 

 

I you bypass the knock sensors, and that solves the problem, then you have an octane issue. Octane is an issue on performance motors. You can put additives in the tank to increase the octane, but you should verify that the octane rating is the issue before doing that.

Rocky Adams Enthusiast

Rocky Adams

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1 minute ago, Supreme Pizza said:

 

 

I you bypass the knock sensors, and that solves the problem, then you have an octane issue. Octane is an issue on performance motors. You can put additives in the tank to increase the octane, but you should verify that the octane rating is the issue before doing that.

Ok thank you. Not to familiar with the octane world. Do you mind if I keep in touch with you for some later on questions?

Supreme Pizza Senior Enthusiast

Supreme Pizza

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1 minute ago, Rocky Adams said:

bypass permanently? Or temporarily?


I have a extra set of OEM knock sensors. Would it be worth it to just try them and see?

 

Disconnect the wires from knock sensors, and connect them to the spare knock sensors. Then ground the knock sensors with jumper wires. Test performance for a short time ( a few minutes at most). Then reconnect the knock sensors that are in the block. Don't drive around with bypassed knock sensors, you will damage the engine. Its just a test to see if detonation is causing retardation, which could be caused by carbon, fuel quality, etc.

CamGTP Senior Enthusiast

CamGTP

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Posted

Knock sensor failures are common. The rear sensor hole fills up with moisture and ruins the sensor and harness most of the time. New OEM sensors and a new harness usually always fixes the problem.

 

Because they are under the intake manifold doing what pizza man said wouldn't even be something I would consider doing for the amount of work that has to be done.

Rocky Adams Enthusiast

Rocky Adams

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1 minute ago, Supreme Pizza said:

 

Disconnect the wires from knock sensors, and connect them to the spare knock sensors. Then ground the knock sensors with jumper wires. Test performance for a short time ( a few minutes at most). Then reconnect the knock sensors that are in the block. Don't drive around with bypassed knock sensors, you will damage the engine. Its just a test to see if detonation is causing retardation, which could be caused by carbon, fuel quality, etc.

Okay. Thank you. 

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