G8 GT Limp Mode - P1516, P2101, P2176

[autoroids]

Every time I get on my car the throttle codes come up, and it goes into safe mode...as stated in the heading P1516, P2101, P2176.

I had a Rotofab CAI with a Cortex tune, and tried to rule things out by removing the CAI putting the stocker back on, and flashing back to stock. It did not help, as it goes into safe mode even in stock form.

I presume this is a bad throttle body???Correct?

It is mighty disappointing with less then 2K on the dile, and coming from and STi and an Evo, the quality on the G8 is beginning to worry me...
:hang:

[WickedMom]

Flo-chart shows either Throttle body or ECM.




Circuit/System Verification

1. Ignition ON, engine OFF, use a scan tool to observe the throttle position (TP) sensor 1 indicated position. Throttle position should increase as pedal is applied, and decrease as pedal is released. When no accelerator pedal activity is detected, the throttle position will return to the spring loaded default position.

Important: A low voltage condition may set this DTC.
2. Review the Freeze Frame/Failure Records and ensure sufficient ignition voltage was present when the DTC was set.
⇒ If voltage was low, verify with the owner that the battery was not discharged. If the battery has not been discharged, refer to Power Mode Mismatch.
3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.



Circuit/System Testing

Caution: Turn OFF the ignition before inserting fingers into the throttle bore. Unexpected movement of the throttle blade could cause personal injury.

1. Inspect the throttle body for the following conditions:
• A throttle blade that is NOT in the rest position
• A throttle blade that is binding open or closed
• A throttle blade that is free to move open or closed WITHOUT spring pressure
⇒ If a condition is found, replace the throttle body assembly
Important: Disconnecting the throttle body harness connector causes additional DTCs to set.
# Ignition OFF, disconnect the harness connector at the throttle body.
# Ignition ON, verify that a test lamp does not illuminate between motor control 1 circuit terminal B and ground.
⇒ If test lamp illuminates, test the motor control circuit for a short to voltage. If the circuit tests normal, replace the ECM.
# Ignition ON, verify that a test lamp does not illuminate between motor control 2 circuit terminal A and ground.
⇒ If the test lamp illuminates, test the motor control circuit for a short to voltage. If the circuit tests normal, replace the ECM.
# Ignition ON, verify that a test lamp does not illuminate between motor control 1 circuit terminal B and B+.
⇒ If the test lamp illuminates, test the motor control circuit for a short to ground. If the circuit tests normal, replace the ECM.
# Ignition ON, verify that a test lamp does not illuminate between motor control 2 circuit terminal A and B+.
⇒ If the test lamp illuminates, test the motor control circuit for a short to ground. If the circuit tests normal, replace the ECM.
# Ignition OFF, allow sufficient time for the ECM to completely power down. Connect a DMM between the motor control 1 circuit terminal B and ground.

Important: When measuring peak voltage, ensure that the DMM is on the proper voltage scale and that the response time is set to 1 ms.
# Measure for B+ on the motor control 1 circuit terminal B as the ignition is turned ON.
⇒ If the peak voltage is not within 1 volt of B+, test the circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
# Ignition OFF, allow sufficient time for the ECM to completely power down.
# Measure for B+ on the motor control 2 circuit terminal A as the ignition is turned ON.
⇒ If the peak voltage is not within 1 volt of B+, test the circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
# If all circuits test normal, replace the throttle body.

[GRRRR8]

With the key off, unplug and plug back in the TB. Inspect the wiring to make sure nothing has rubbed anything.

Did this happen all of a sudden or after the Cortex?

[autoroids]

This happened all of the sudden...had the Cortex since 600 mi on the G8, now I am at 1705 mi, and it is happening very consistently. It happens when I get on it, not even WOT, just get on it, maybe 75% of WOT or so.

Does anyone know if the LS3 and L76 throttle bodies are the same or interchangeble? Is there a benefit to getting an LS3 throttle body, if that is the culprit?

[GRRRR8]

Same thing, 90mm.

[autoroids]

Thanks guys appreciate the feedback!!!

[autoroids]

Well, checked out the harness and the t-body...it all looks good, and checks out. The t-body's plate moves just fine, and does not get stuck, nor is it loose. Might be the ECM...will let you all know, gotta go by the stealership tomorrow.

[autoroids]

OK, picked up the car from the local dealership, but I am not very sure that their techs are good. Their said the following:

"Found codes P1516, P2101, and P2176. Found a bulletin pertaining to the customer's concearns. Checked all grounds. Tightened battery cables at battery and junction block.cleared code and rechecked."

I asked the advisors for explanation, and got a song and a dance. I explained that I never had a problem starting the car, and it only happens when I get on it. They said that possibly because of the bad connection at the battery the voltage was lower, and that is what triggered the codes. Too bad that there is snow everywhere, and I can't test the car anywhere...

What do you all think?

[SRG963]

OK, picked up the car from the local dealership, but I am not very sure that their techs are good. Their said the following:

"Found codes P1516, P2101, and P2176. Found a bulletin pertaining to the customer's concearns. Checked all grounds. Tightened battery cables at battery and junction block.cleared code and rechecked."

I asked the advisors for explanation, and got a song and a dance. I explained that I never had a problem starting the car, and it only happens when I get on it. They said that possibly because of the bad connection at the battery the voltage was lower, and that is what triggered the codes. Too bad that there is snow everywhere, and I can't test the car anywhere...

What do you all think?

I had one of the first loose cables reported online. Totally disabled my car, locked the key in the car, and wouldn't respond to anything. I never got any codes, just a dead car. I was instructed to removed the battery cable (thanks VMS) and reattach. That's when I noticed the cable could be pulled off by hand.

Long story short, if it happens again, take it to a different dealership.

[Markszz4]

Im reading this and thinking about all the problems the GTO's had with faulty gas pedal asm''s.

[KEV-O]

OK, picked up the car from the local dealership, but I am not very sure that their techs are good. Their said the following:

"Found codes P1516, P2101, and P2176. Found a bulletin pertaining to the customer's concearns. Checked all grounds. Tightened battery cables at battery and junction block.cleared code and rechecked."

I asked the advisors for explanation, and got a song and a dance. I explained that I never had a problem starting the car, and it only happens when I get on it. They said that possibly because of the bad connection at the battery the voltage was lower, and that is what triggered the codes. Too bad that there is snow everywhere, and I can't test the car anywhere...

What do you all think?

i had the same problem when removing my intake, couldn't get her up past 1500 rpm as it would go in to safe mode
unplugged my battery, waited 10 minutes, hooked it back up, all was fine, never had a problem since

[DRCUSTOMPARTS]

It wouldn't hurt to clean the MAF with MAF cleaner. The RotoFab has an oiled filter and that oil can sometimes contaminate the MAF.

[autoroids]

i had the same problem when removing my intake, couldn't get her up past 1500 rpm as it would go in to safe mode
unplugged my battery, waited 10 minutes, hooked it back up, all was fine, never had a problem since

What do you mean by that Kev? Removing the stock one, and putting an aftermarket one on?

[KEV-O]

What do you mean by that Kev? Removing the stock one, and putting an aftermarket one on?

sorry, yes i put an aftermarket on, and went to go for a test drive, couldn't get up past 1500 rpm, disconnected the battery, let it sit for 10 mins, hooked it back up and all is fine since