my 96 discovery with 36,000 mile on it (yes its true) started to lose power about 3 times today at about 55mph,it starts up idles and runs great and i run 93 oct gas help???
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What has been done to it tune up wise?
Initally it sounds like you might have a bad VSS, but I would want more info before I really pushed that idea.

 

well it has new plugs and the car is almost new for its age it droped from 55 to 50 then i gave it the gas ran ok it did it a couple of more times what is a vss???? thanks!!

 

VSS is the vehicle speed sensor, common problem. The VSS fails intermittently and tells the computer the truck is going like 150 MPH so the computer shuts down a bank of injectors. You need to get it on a scan tool and see if there are any codes stored and post that info. Other common failures are the Mass airflow sensor and sticking exhaust valves causing intermittent misfires. You would need to hook up a vacuum gauge and watch for bouncing vacuum readings when it is acting up to diagnose that. In other words it could be a few different things.

 

its does run alittle rough untill it warms up would it be safe to replace the vss and the mass air flow???and r they easy to replce or will i have to reset codes and so forth???thanks for your help...