Major FLAW discovery with Electronic throttle control with MAP sensor equipped engines

[Bigkevschopshop]

1 word sums this up.... HYBRID...….

I have heard somewhere that on hybirds if the electrical system has any issues, it can reek havoc on the gasoline systems... Catch can is cheap insurance... putting mine on this weekend on my fossil burner... Any motor can have oil consumption issues, it used to be quite common back in the day for one to burn and another to never use an ounce... Now tolerances are tighter etc...Better qc... But Gummed up oiled sensors can do weird things. My suggestion is to get the dealer to reflash the computer... Full relearn process will feel weird for a bit but it will fall into line for sure... But I'm just a big grey bearded guy what do I know?

Good luck with things man... I know it gets frustrating, but sometimes a 200 dollar trip to the dealer can save you a lot down the line... I don't suggest dealer for everything but for PCM woes and weird crap its worth it.

 

[Bigkevschopshop]

The TPS wiring harnesses have a known issue with corrosion and broken internal wires. No doubt these components can cause a throttle problem since they're directly connected to the throttle. That’s way different than a MAP sensor doing it. You can install a new pigtail on the TPS but be sure to solder and heat shrink the wires, it’s sensitive.

Makes us old guys miss cables hearing this...haha..

Good damn point for sure man, forgot about the corrosion issue in the harness.

 

[Kraig]

Ya know, I heard a guy say one time that, even though GM put MAP sensors on MILLIONS of vehicles, that they’re totally not required. You should probably just take it to Pep Boiz and have them take it off and it’ll solve all your problems.

 

[Rocket Man]

Ya know, I heard a guy say one time that, even though GM put MAP sensors on MILLIONS of vehicles, that they’re totally not required. You should probably just take it to Pep Boiz and have them take it off and it’ll solve all your problems.

 

[Doubeleive]

wide open throttle issue's I have seen before, because of the throttle body or improper assembly of the intake, it can be kind of scary if you are not prepared to deal with it i.e. shut off the ignition, take it out of gear, etc I can see how accidents can occur as a result, these stories of people going for longer distances or even miles and not being able to stop are kind of ridiculous sometimes though.

 

[Trey R]

The TPS wiring harnesses have a known issue with corrosion and broken internal wires. No doubt these components can cause a throttle problem since they're directly connected to the throttle. That’s way different than a MAP sensor doing it. You can install a new pigtail on the TPS but be sure to solder and heat shrink the wires, it’s sensitive.

I am totally down to try that,but it does it at random timesit's never consist of a broken wire.

 

[Rocket Man]

I am totally down to try that,but it does it at random timesit's never consist of a broken wire.

Sometimes the wire is still making half-ass contact until something like the engine moved a tiny bit or just vibrations cause it to lose contact for a sec. The wires sometimes break inside the insulator do you can’t see it and they make intermittent contact. It’s suggested you pull on each wire to see if it’s just the plastic insulator that’s holding it together. If the plastic stretches you know the wire is broken inside.

 

[Trey R]

Sometimes the wire is still making half-ass contact until something like the engine moved a tiny bit or just vibrations cause it to lose contact for a sec. The wires sometimes break inside the insulator do you can’t see it and they make intermittent contact. It’s suggested you pull on each wire to see if it’s just the plastic insulator that’s holding it together. If the plastic stretches you know the wire is broken inside.

I will definitely see what up with it.

 

[BG1988]

I still have NOT had any of the issues with the replacement sensor with


1-½ drive cycles so far and no engine run away from a auto start...

and the numbers for the sensor are changing


but it still should not cause an engine runaway.. even if there was a fault with any sensor... just like the throttle plate and gas peddle have fail safe they must match as one voltage rises the other voltage drops and vise versa when the gas peddle is depressed one voltage rises the other voltage drop)...
That is how the fail safe works and if there is an issue it should have entered limp mode with "reduced engine power"..

so there is a computer software bug issue
That overrides the fail safe implemented


We all ready know GM has a limp mode if there is a throttle position sensor issue it's pretty clear it failed to enter limp mode as the two voltages did not match.. (the gas position sensor did not match the throttle plate position sensor) at lest they have to be very close in in terms of the voltage, a lest it will be unnoticeable to the user in the NNBS (NBS has a noticeable lag time)

 

[iamdub]

I still have NOT had any of the issues with the replacement sensor with


1-½ drive cycles so far and no engine run away from a auto start...

and the numbers for the sensor are changing


but it still should not cause an engine runaway.. even if there was a fault with any sensor... just like the throttle plate and gas peddle have fail safe they must match as one voltage rises the other voltage drops and vise versa when the gas peddle is depressed one voltage rises the other voltage drop)...
That is how the fail safe works and if there is an issue it should have entered limp mode with "reduced engine power"..

so there is a computer software bug issue
That overrides the fail safe implemented


We all ready know GM has a limp mode if there is a throttle position sensor issue it's pretty clear it failed to enter limp mode as the two voltages did not match.. (the gas position sensor did not match the throttle plate position sensor) at lest they have to be very close in in terms of the voltage, a lest it will be unnoticeable to the user in the NNBS (NBS has a noticeable lag time)

You should be reporting your discovery to GM, not to a forum full of MAP sensor fanboiz. Let us know what they say and do about it. While you have their attention, ask 'em about their resolution for the potentially exploding air bag inflators.