Limp Mode?

[gddeadeye]

Drove back from Nashville, TN yesterday to Fredericksburg, VA. The trip out there was fine with no problems. Truck has acted up in the recent past a little but had never thrown the check engine light until I was 200 miles from home. Got off the interstate to get dinner and when I got back on the light came on, truck wouldn't go over 2000 RPM. Would do 45 MPH in 3rd gear until I got on level ground or downhill and then would upshift when I let off the pedal. If I got too much speed (over 65MPH) it would downshift again and slow to 2000 RPM. Going to run the codes tonight but just wanted to see if anybody has had this kind of problem so I know what I might be looking at. Truck is a 2004 2500 HD. 152,000 miles. Thanks in advance.

[DmaxMaverick]

Welcome aboard!

Don't overlook the most simple of solutions. Sounds very much like it's time for a fuel filter change. The DTC (read the code) may indicate something else, but you won't know until it's read. If any code(s) are fuel system related, look for a plugged fuel filter, fuel system restriction or air (suction) leak before anything else. Most often, it's that simple. It doesn't sound like "Limp Mode", as it's commonly seen.

[Kennedy]

When issues like this arise it is SO handy to reach back and grab a restriction gauge and know exactly what is going on.


http://www.kennedydiesel.com/images/Dmax-fuel-filter-rest1.gif



Then to read codes:

http://www.kennedydiesel.com/images/RDT51.jpg