dennis55753
Junior Member
I've been noticing lately that when driving my truck but not under a load that my RPMs are fluctuating. Not very much probably less than 100 RPMs but you can hear the engine going up and down ever so slightly. It's annoying. It does not do this when accelerating but when going down the road between 45 and 60 miles an hour. RPMs do not fluctuate when idling.Also when I left my truck to idle in park it died on me several times but not very often. But it would start up right away and stay running.Check engine light or other warning lights have not come on. Put it on diagnostic tool and there was no trouble codes.I've changed the idle air control valve and the throttle position sensor a few days ago. The RPMs still fluctuate but I do not know yet if the motor will die again when idling because this did not do all the time. So I do not know if what I changed solved the stalling problem when idling. But in the past several months I've change the fuel pump, spark plugs, spark plug wires, coil, and a new battery. The motor runs great, starts good, accelerates good, shifts perfectly, and has good power. But it always got terrible gas mileage between eight and 11 miles gallon. But the fluctuating RPMs is annoying. Any ideals? The truck has 157,000 miles on it and a brand-new automatic transmission right from the dealer was put in at 143,000 miles. It's a ram 1500 4 x 4 with a 5.9 motor.
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