acceleration problem

I've been having engine surging/acceleration problem with my manual 89 240sx. It starts ok, idle is ok, if I step on the gas while parked and in neutral its ok. But when I'm driving and I step on the gas too fast I feel my engine reving/surging and there's no change on the acceleration. Read a lot of similar post so I tried some of the suggestions. This is what I have done so far.

1.) Replaced the BPT valve with OEM BPT
2.) Replace vacuum line connected to BPT
3.) Checked all vacuum lines, none seems to be cracked, kinked, or broken.
4.) Replace fuel filter
5.) Replace spark plugs with NGK
6.) Replace spark plug wires
7.) Clean air intake
8.) Replace air filter
9.) Replace clutch slave cylinder. It was leaking, I thought the clutch was sticking but that didn't help.
10.) Took it to the dealer and told me that the check engine light is not working. I told them that its not going to work because I don't have one. They didn't fixed the problem and I still have to pay $88 just for them to say we don't know what's wrong.

I haven't done anything to the EGR, PCV, and AIV. Can anyone show me where the AIV is. A pic would be great. I have read a lot of thread about how to clean it but I'm not sure where it is exactly.

Thanks

clean out your mafs.. if that doesnt help then you'll need a new one

Your clutch is slipping, get a new one.

i think we're picturing two different things.. we need more details about what reaction the car gives when you put your foot on the gas. if the revs go up smoothly when you gas it but you don't accelerate as quickly as it sounds like you should, then yes, logik is right. but if your engine is surging or sputtering and struggling then it sounds like your mafs

Speaking of slipping clutches, my dad told me to take his Altima to the car wash last night, so obviously 5 minutes later I'm going 150kmh(90mph) on the freeway, the problem was, when I merged onto the highway, I'm flooring it through every gear, but nothing happens since the clutch is finished, was so anoying!!! Couldn't have any fun, but it was still cool...anyways...

i drove this 2002 celica gts that had been traded in after a year and the clutch was absolutely toast.. which was too bad cause the gts is a very fun car to drive..

Describe whats happening better. When you push the gas, do the rpms rise? Or does the car just kinda bog or buck? More input needed.

I'm not sure on the E, but on the DE the AIV is the black box on the drivers side of the engine bay with hoses running from the exhaust manifold to the air filter box. Easy to find. Its right in front of the master cylinder and beside the power steering resovoir.

I cleaned the mafs with qtips and alcohol and its still the same way. I'll take a look at the AIV next.

When I'm starting from a stop, its ok. Once I'm driving let's say 45mph on 4th gear and I try to push the pedal some more before changing gear, the revolution increases but there's no change on the speed. The tachmeter goes up and I can hear the engine. It doesn't sputter or anything, it sounds like stepping on the gas pedal in neutral. Once I let go of the gas, the RPM goes back to where it should be. It does this on all gears not just on fourth. Although I haven't really pushed hard on 1st gear to notice it. I don't have any problem shifting. As long as I don't push the engine hard (stepping on the gas pedal) It seems to be running ok. :banghead: hope this helps

Your clutch is finished, that's the problem, no buts, you need a new clutch.

yeah, logik is right.. and you probably have a funky smell going through your car when it happens right??

Like I said before, its the clutch. Jeez.....

nah, nobody has mentioned this: the clutch.. thats your problem.. i take all credit for that one


haha jk nissanfanatic

OH! It sounds like a cue for me to say "it's the clutch!" Right?! RIGHT?! All I ever do is agree with you guys! It's gotta be the clutch!
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(that's for you d-bo)

My 93 fb has a problem too..... if i get on it for a while(few mins) it will die out like its hitting the speed limiter, but it goes all the way down to 2500 rpms then starts bucking very violently... the maf looks clean and the harness isnt cut any where so i dont know whats up..... anyone else have this problem or know what it is????

OH! It sounds like a cue for me to say "it's the clutch!" Right?! RIGHT?! All I ever do is agree with you guys! It's gotta be the clutch!
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(that's for you d-bo)


yeah i gotta agree with you drumpet, sounds like the clutch lol, i dont think d-bo was being offensive or anything, just a suggestion.

no, like i said.. no offense

I know, man. I was just referring to our conversation in the other thread about me not saying anything good...:)