I bought a 2003 Dodge Ram 1500 5.7 hemi back in July it ran fine not many problems besides ball joints and stuff fixed it all. Driving it and a few months go by it starts to act up. The lightning bolt will start flashing sometimes and won’t go past 2.5k rpms and I can shut it off and it’ll drive fine for awhile or it’ll do it still. The truck does not have any cats on it previous owner cut them off and doesn’t have an egr valve either(idk why) only codes it’s throwing as of now it’s o2 sensor codes. It has thrown a small evap code but goes away here and there. Sometimes I can drive it fine without issues other times just does that lightning bolt flashes and like goes into limp mode. It has also once while at a stop light started revving up on its own and going to like 5k rpm’s truck is trying to do a burnout or something I threw it in park and shut it off until the light turned green. Drove it to a parking lot it only wanted to drive 5mph, but revving up the entire way and shut it off for about 30 minutes and drove it home fine like 10 miles away. Haven’t really drove it since, but a few times it starts revving up on its own and the lighting bolt comes on. If it’s in park it‘ll idle fine sometimes for the most part sometimes as soon as I put it in drive immediately starts idling between 700-1k rpm just up and down goes back into park maintains a normal idle. Any ideas on what it could be? Some people told me to put an egr valve on it and some have said it could be the throttle body bc it’s electronic on these, but not sure what to do yet. Could it be a sensor or what y’all think?

 

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