Hello Everyone,

I'm new to the forum and new to HP Tuners. Thanks in advance for any feedback on this issue.

I swapped a 2018 Ram 5.7 (and HP70) into my Jeep earlier this year. I also installed a Ram 6.4 intake on it before first start. Shortly after getting it on the road, I purchased HPT credits that would allow me to increase the intake volume, which I did. Other than that, the tune is what Jeep Speed Shop sends with the ECM. At idle, my long-term fuel trim on both banks is close to zero and the short-term fuel trim on both banks fluctuate but stay +/- zero range. I determined that at about 1300 RPM, the LTFT jumps to about +18 on both banks and stays there. That happens when I start traveling or when I increase throttle with the brakes pressed. The STFT seems to stay about +/- zero. I suspected vacuum leaks until I learned that the issue would be sort of opposite with high LTFT numbers at idle instead. The MAP sensor I am using is from the 5.7 intake and had about 1000 miles before the swap, so it is new. The Jeep had 130k miles at the time of the swap so it could be fuel filter/pump related. I didn't change the fuel pump or filter and I increased the fuel line diameter to 3/8" from the quick-connect under the passenger side floorboard up to the intake. I am using the stock 5.7 injectors with a Fore injector spacers.

Any advice on the reason my LTFT numbers are high under load would be greatly appreciated.

Matt