1997 Nissan Pickup, 4wd, 5spd. Engine feels like it has a rev limiter set at 3400rpm. Stumbles in all gears at this rpm and then gets going again at about 3800rpm, but still stumbles -- but not nearly as badly at 3400rpm. Check engine light is on and NAPA mechanic says the code that comes up is for a sensor that monitors the recirculated gas fumes and it is not responsible for the stumble. And, he cannot fiure out what is causing the stumble.

SOURCE: 97 nissan maxima

throttle position sensor,or egr valve,also check your air filter,if this helps please gine me a fix ya vote

SOURCE: service engine soon

Hello it sounds like you might have a bad map sensor the smell your smelling is raw fuel being dumped and being burned in the exhaust test the map sensor to see if it within range ,if it checks out okay check your iac motor idle air control valve if the pintle gets stuck in the bore it will cause stumbling ,hesitation,even no start conditions,goodluck please rate

SOURCE: 2003 Nissan Altima 2.5S, Check Engine Light Problem.

this problem could be caused by the mass air flow censor, i had the same problem with my car. it is really pricey at the dealer so you might want to check elsewhere for this part. I found one at a scrap yard for 85% less that the dealer and i also got life time warranty, the dealer does not offer any warranty on this part.

SOURCE: Too high engine rpm at freeway speeds

that is a normal rpm for the nissan pickup (hardbody)

SOURCE: 300zx erratic idle 1993 n/a

Your Idle Air Control Valve is at fault. These never set a code when they fail and they always fail.

Check this item out on eBay.

http://cgi.ebay.com/ebaymotors/nissan-300zx-OEM-idle-air-control-valve-IACV_W0QQcmdZViewItemQQ_trksidZp3286Q2em20Q2el1116QQhashZitem5189d6b9f7QQitemZ350204901879QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

They aren't usually this expensive so search the net and you should find a much better deal.

You shouldn't need to worry about the gasket when replacing this. They usually don't tear and stick to the manifold. If it does tear though you should replace it