97 Nissan truck, 2.4L, 4X4, 134,000 miles. About a month ago, i put some sea foam into a vaccum hose hoping to clean out some carbon and possibly improve MPG. A few days after this my check engine light came on. I assumed maybe a O2 sensor or something. Kept driving with light on. A few weeks later, I was on the highway in 5th and it felt like I lost power. I stopped, tried to take off and it chugged along like I was taking off in 2nd. I stopped, pressed on the gas in neutral and the throttle just reved up and down with the pedal all the way to the floor(acted like i was pushing up and down on the pedal when the pedal was fully engaged). Shut the engine off took the battery cable off to reset computer. this cured the check engine light and temporarily the throttle problem. Anyway, it's a few weeks later and occasionally it will act up. Called a Nissan dealer, answer, Mass air flow ($427, ouch!!). Does this sound like the problem?

 

Did you pull the dtc first? Could be mass air flow meter. Does it run fine at low rpms?

 

dtc? pulled the code for the check engine light=intake air temp sensor. I don't think that is theproblem though. runs fine at an idle it revs up and down when you step on the gas. My dad was conversing on the net about the problem and some guy replied that it sounded like a loose battery cable. I do have a loose (neg) battery cable. Could this be the problem? It sounded strange to me that a loose cable could cause this.

 

dtc = diagnostic trouble code. Does your car ever give you problems starting? If not I would not stress the loose cable (I reserve the right to be wrong, but I don't believe thats it). If your local dealer is nice go down and ask if the can hook the consult up and check the air fuel alpha's, Most times a bad maf sensor throws those off which usally throws a code for a lean condition. Although the ecu can go into fail safe mode when that code (for air intake temp) is detected. Just my 2 cents