Hi, I recently bought a 97 Dakota 2Wd, 3.9L. It started to ping once it warms. On the first time the truck is started, it sound like new, no mechanical sounds, it sounds strong like it was electrical but no, it is fuel powered . Have tried: complete tune up, new CrankShaft P. Sensor And IAC; both thanks to the CEL, lower Temp t-stat, higher octane fuel. well with a higher octane fuel the symptom seems to disappear but not at all. As much I have found it looks that there's a vacum leak *on the plenum*, have to check tomorrow on the day for the oil puddle in there.

And to make things worse, the fuel gauge just start to act weird. The first time I was on the red signal and noticed that it was turning to the left to "E" so I parked the truck then checked under it looking for leaks but no. after turning on the truck again everything was normal, almost full tank. But now it is working like a turn signal, on city and highway, drops down, then the pump lights, the chime and then back to where it belongs.

Now Im more confused, could be a ground issue on both? or the fuel pump is diying? ...

 

The plenum gasket would be my first guess on the pinging. For the fuel guage, it may be a ground wire or just any wire. But most likely it is the float that is miss adjusted. The sending unit probably need to be position right.

 

Have'been busy, a lot. I hope this weekend i'll have a nick of time to check the gasket, and even the time to drop the fuel tank or remove the box looking for bad conections...