'90 240sx 3rd Gear Trouble

[stopatnothing]

I just bought this car, knowing it needed some work and I expect to do my share of it... It runs fine at full throttle all the way through the 1st and 2nd gears but when I get to about 5000-5100 RPMs in 3rd they just drop back down and I have to reduce my speed. It feels almost like a governor kicking in or something. I dont hear any knocking, the car doesnt shake or studder, and I dont smell anything that I shouldnt, they just drop and I slow down. Has anyone else had this problem or have any idea what it might be or know how to take care of it?

Thanks

[stopatnothing]

Anyone?

[stopatnothing]

I changed out the spark plugs earlier today and and now the "kick" (I'll just call it that for now) doesnt happen in 3rd gear anymore, now it happens in 4th. This doesnt make any sense to me... Can someone help me understand this and if theres a way to fix it (besides getting a new transmission)

[Dieselman]

I'm assuming that we're talking about an automatic here?

[stopatnothing]

Nah, it's a manual. And it happens waaay after I shift, between 5000-6000 revs so I dont think it's anything I'm doing... I hope.

[rogoman]

You might be having a fuel delivery problem; start by changing the fuel filter.

[stopatnothing]

will do, thanks.

[Daily Driven 240]

hey um in not 100% sure but i think that stock 240sx have a rev limiter in 4th and 5th gear and cuts at 5,000rpm in both those gears.

[stopatnothing]

do you know how to either set that higher so it wont affect me or even just take the rev limiter out?

[stopatnothing]

changed out the fuel filter and it was fine for about 2 days but earlier tonight it started up again. any other ideas?

[CotBU]

Check the transmission sensors for 4th and 5th also check the VSS and the Speed sensor input wire at the ecu.

[240sxvaj]

im not 100% sure but im thinking its ur O2 sensor, it might be burn'd out. i wouldnt feel no pull when i swith to 3rd until my bro (a mechanic) found out that it was my O2 sensor so after i change it i can feel a BIG difference on 3rd gear to 5th gear.