Codycat91
Member
I want to start by saying I am not complaining or blaming Cobb or any tuner. For all I know I could be doing something wrong and be the cause of my troubles. I am writing this to document the issues I've been having and hope to find a solution.
Background: I have a 2021 F150 XLT/FX4 3.5L Ecoboost, 6.5' bed, extended range tank. It has an S&B intake and Nitto Recon Grapple 295/70/18 tires on TIS wheels. Nitto lists the tire height on their website as 34.29". I strictly run top-tier 93 octane fuel from Mobil.
I installed my Cobb Accessport tuner on July 8th 2023 with a custom tune. Began the datalogging process and eventually came to final revision. When first driving the truck with the tire height set to 34.3" I noticed my speedometer was pretty far off. Ended up playing with the sizing and landed on 33.2" tire height which made my speedometer match my GPS speed all the way up to 95mph exactly.
Occurence #1: July 11th, while driving the truck, the transmission made a horribly violent aggressive clunk and the whole truck momentarily lost power and rebooted while driving. Check engine light and wrench icon on. I pulled over and read codes P05AE and P061A (Internal Control Module Torque Performance). I cleared the codes and continued on without issue.
Occurence #2: July 23rd, again while driving under normal conditions, truck momentarily lost power, rebooted along with the AP, trans made a horrible violent aggressive bang, and I got code P061B (Internal Control Module Torque Calculation Performance). Cleared code and continued again without issue.
Occurence #3: August 4th, I had just driven over 8 hours from NY to Chicago, and while pulling into the Chicago airport, the same thing happened. This time I specifically remember I was pulling into the departure zone and not even on the gas. The truck again made a horrible violent clunk and got a CEL again. I did not take a picture of the code this time.
Occurence #4: August 19th, again normal driving, same thing, code P061B (Internal Control Module Torque Calculation Performance). I had a passenger in the truck this time and the clunk was so violent, she yelled "OMG Did you just hit something?!?" Pulled over, cleared code and reset ECU, still in limp mode, reflashed tune, decided to try a canned Cobb tune instead of my custom tune to see if it would make any difference.
Occurrence #5: August 26th, I was traveling at 78mph on the highway, had been on the road all day, visited some people, and was heading home at 10pm. Out of nowhere, horrible violent clunk, wrench light and limp mode. Code this time was P161C (no description available) I had to pull over on the side of the highway in the dark. Tried clearing CEL and truck was still in limp mode. Decided to just reflash to factory and reach out to Cobb directly this time.
Occurence #6: Sept 2nd, Just happened again, with the Cobb OTS stage 2 tune on the truck and tire height set to 33.5" per Cobb's instructions. This time though no trouble codes however did get violent trans clunk with momentary loss of power to truck and to tuner, error message on dash said "drive mode not available." Reset to factory flash and awaiting further from Cobb.
Cobb requested a copy of the diagnostic file off the AP which I sent over. They replied that this code is attributed to tire size being slightly off. I find this weird because my speed was consistently perfectly matching my GPS speed (still on the 33.2" setting). And even if that last code is attributed to a tire size issue, it still doesn't explain the rest of the codes. So I called Cobb on the phone and spoke directly with a tech while verifying I was entering the exact tire size they wanted. I parked in a level parking lot, had a level on top of my tire and a tape measure. Rear tire height measured 33.5" and front tires measured 33.25". Being that the truck is rear wheel drive, they wanted me to set the tire height to 33.5". This was yesterday. Driving around today, something just doesnt feel right and I can tell its going to do this again. Part of me is dreading it because its so violent, I'm sure it will eventually cause some damage to something, but at the same time I want it to happen again so I can try to capture it in a datalog and get to the bottom of the issue.
Does anybody have any advice/input/suggestions, anything to help at all???
Background: I have a 2021 F150 XLT/FX4 3.5L Ecoboost, 6.5' bed, extended range tank. It has an S&B intake and Nitto Recon Grapple 295/70/18 tires on TIS wheels. Nitto lists the tire height on their website as 34.29". I strictly run top-tier 93 octane fuel from Mobil.
I installed my Cobb Accessport tuner on July 8th 2023 with a custom tune. Began the datalogging process and eventually came to final revision. When first driving the truck with the tire height set to 34.3" I noticed my speedometer was pretty far off. Ended up playing with the sizing and landed on 33.2" tire height which made my speedometer match my GPS speed all the way up to 95mph exactly.
Occurence #1: July 11th, while driving the truck, the transmission made a horribly violent aggressive clunk and the whole truck momentarily lost power and rebooted while driving. Check engine light and wrench icon on. I pulled over and read codes P05AE and P061A (Internal Control Module Torque Performance). I cleared the codes and continued on without issue.
Occurence #2: July 23rd, again while driving under normal conditions, truck momentarily lost power, rebooted along with the AP, trans made a horrible violent aggressive bang, and I got code P061B (Internal Control Module Torque Calculation Performance). Cleared code and continued again without issue.
Occurence #3: August 4th, I had just driven over 8 hours from NY to Chicago, and while pulling into the Chicago airport, the same thing happened. This time I specifically remember I was pulling into the departure zone and not even on the gas. The truck again made a horrible violent clunk and got a CEL again. I did not take a picture of the code this time.
Occurence #4: August 19th, again normal driving, same thing, code P061B (Internal Control Module Torque Calculation Performance). I had a passenger in the truck this time and the clunk was so violent, she yelled "OMG Did you just hit something?!?" Pulled over, cleared code and reset ECU, still in limp mode, reflashed tune, decided to try a canned Cobb tune instead of my custom tune to see if it would make any difference.
Occurrence #5: August 26th, I was traveling at 78mph on the highway, had been on the road all day, visited some people, and was heading home at 10pm. Out of nowhere, horrible violent clunk, wrench light and limp mode. Code this time was P161C (no description available) I had to pull over on the side of the highway in the dark. Tried clearing CEL and truck was still in limp mode. Decided to just reflash to factory and reach out to Cobb directly this time.
Occurence #6: Sept 2nd, Just happened again, with the Cobb OTS stage 2 tune on the truck and tire height set to 33.5" per Cobb's instructions. This time though no trouble codes however did get violent trans clunk with momentary loss of power to truck and to tuner, error message on dash said "drive mode not available." Reset to factory flash and awaiting further from Cobb.
Cobb requested a copy of the diagnostic file off the AP which I sent over. They replied that this code is attributed to tire size being slightly off. I find this weird because my speed was consistently perfectly matching my GPS speed (still on the 33.2" setting). And even if that last code is attributed to a tire size issue, it still doesn't explain the rest of the codes. So I called Cobb on the phone and spoke directly with a tech while verifying I was entering the exact tire size they wanted. I parked in a level parking lot, had a level on top of my tire and a tape measure. Rear tire height measured 33.5" and front tires measured 33.25". Being that the truck is rear wheel drive, they wanted me to set the tire height to 33.5". This was yesterday. Driving around today, something just doesnt feel right and I can tell its going to do this again. Part of me is dreading it because its so violent, I'm sure it will eventually cause some damage to something, but at the same time I want it to happen again so I can try to capture it in a datalog and get to the bottom of the issue.
Does anybody have any advice/input/suggestions, anything to help at all???
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