2018 Roushcharged P0120 code

[1100saber]

I have a 2018 Roush Charged GT that I purchased in June of last year. I am having an intermittent P0120 code that puts the car into limp mode. Barely moves under its own power. It seems to come on at random points under cruising speeds. I have had it come on driving on the hwy with cruise control on, other times under light acceleration at less than 30mph. I brought it to dealer last summer and although they couldn't reproduce the problem they said they fixed what they suspected was faulty wiring connection. Since then it came on twice last fall. I quick restart and or clear code would fix it for weeks at a time. This past weekend it happened again and would not clear. I had to limp the car back to my house. Of course the next day code was gone, and car running great. I will be bringing car into local dealership who I have a great relationship with....but they are NOT a Roush dealer, and don't think their mechanics have ever done an installation of one. The dealer that I purchased the car from/installed supercharger is approx 200 miles away and bringing it there really isn't an option at this point. Just reaching out to see if any one else has encountered this type of situation before?

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[ROUSHCHARGEDS550]

I don't have a 18.. I have a 15 roushcharged GTPP, for what it's worth the car sounds like its in warranty? Have you contacted Roush directly? If not call and ask for Gavin he is knowledgeable with these types of problems.. my personal opinion is it NEEDS to go to a Roush dealer they have the software to flash the car and work directly with Roush hope everything works out for you I know it can be activating!!

 

[ROUSHCHARGEDS550]

That sounds like a TPS throttle position sensor code, look around the throttle body make sure the connections are tight.. does the car have a Roush calibration or do you have a aftermarket tune? I personally wasn't a fan of the Roush cal.. very conservative.. either way hope it works out in sure you will get it figured out

 

[Chainsaw]

The early 2018 Roush supercharger kits used an analog gt350 throttle body. Roush used a sent module adapter to convert the analog data to digital. This adapter is located in your battery box. Roush is now shipping a digital throttle body with the kits. Have your dealer contact Gavin at Roush and have them replace the throttle body with a new digital one. I got mine replaced.

 

[1100saber]

The early 2018 Roush supercharger kits used an analog gt350 throttle body. Roush used a sent module adapter to convert the analog data to digital. This adapter is located in your battery box. Roush is now shipping a digital throttle body with the kits. Have your dealer contact Gavin at Roush and have them replace the throttle body with a new digital one. I got mine replaced.

I had a quick look last night. It appears my setup has the early analog throttle body. I will be making some phone calls today. Thanks for the heads up.

 

[1100saber]

Just want to give shout out to "Chainsaw" and Gavin at Roush performance. I made a quick phone call to Roush this morning and described my situation. Gavin quickly confirmed that I needed a new throttle body. My local (non-roush) dealer is making a call to Roush to get set up for warranty work. Gavin offered to over night the new throttle body to them so that it can be there waiting to be installed when I drop my car off.

 

[hlfbkd420]

Just to confirm, the adapter above is in the battery compartment of the engine bay?

 

[Chainsaw]

Just to confirm, the adapter above is in the battery compartment of the engine bay?

That's where the installation instructions said to put it. If you don't see that adapter in your battery box, either the installer put it elsewhere, or you have the digital throttle body and don't need the adapter.

 

[hlfbkd420]

So... This looks to be the old style?

 

[Chainsaw]

So... This looks to be the old style?

Yes.

 

[hlfbkd420]

I spoke with Gavin at Roush this morning and verified that I DO have the latest calibration. He also mentioned that "some" of the early units have been giving people trouble but if it's not throwing up a CEL, it probably isn't a problem. He mentioned I should take it to AutoZone and see if there are any stored codes. If there are I should take it to dealer and have them contact Roush. I mentioned that when I had it dyno'ed in 7th gear there was a blip in power from 5500 to 6200 and he said it may have been the calibration preparing to cut power for the rev limiter. He also said Roush recommends you dyno the car in 5th gear.

I haven't seen any CEL's but I have experienced where it wouldn't "go" when cruising on the freeway. Kind of like when you hit the rev-limiter.

 

[Dsand300]

I contacted Roush and spoke with Jeffrey Moore of Technical Support. He was very helpful with diagnosing my vehicle's issues. Here is what he replied back to me in an email: "Anytime we see these two codes (P0120 & P0124) together on our Roush 18-21 kit, it indicates the SENT module is going bad."
As instructed by Mr. Moore, I ordered a Bullitt throttle body M-9926-M50B to replace the current throttle body. Mr. Moore stated: " You will no longer need the SENT module. We recommend you discard that and the harness that goes from the SENT module to the throttle body, along with the old throttle body, and replace them with the M-9926-M5 0B throttle body. "

I am now waiting on the replacement Bullitt throttle body M-9926-M50B shipment, so I can do the modifications needed.

 

[Dsand300]

April 7, 2025 update:

This weekend my son and I replaced the analog GT350 throttle body (TB) with the 2019 Bullitt digital TB I received from Summit.
Jeffrey Moore of the Roush Performance technical support desk supplied instructions and a Roush software PCM update to my Roush Stage 1 TVS 2650 setup. The update was flashed into the vehicle's PCM using the Dash Logic dashbridge CX interface with the Roush Diagnostic Tool (RDT) software..

Long story short, the flash and throttle body replacement was successful. The new updated tune started the vehicle immediately. Test drives were successful! No Ford Service Center was involved with the process. This should take care of the P0120 and P0124 codes caused by the analog to digital conversion module and the GT350 TB.

Many thanks to Mr. Moore of the Roush technical support desk for his patience and guidance during the conversion!

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