Surging acceleration fix??

[Dattebayo]

True i think we went through all that earlier though. 240sxer, on the old forum there used to be a post on the FAQ called, "car running a little sluggish? Try replacing you IAC/AAC valve!" And it turned out to be true. Go to your local auto store and look at the Altima book under emissions devices and for some stupid reason its in that section, and exactly the same as the 240's design, except that its on the opposite side of the engine.

[p00t]

I have this problem as well, I recently installed a new distributor cap and rotor, which helped alittle, bit problem is still there... im sure its the stupid idle control valve.

only thing detering me at the moment is that you have to basically take off the intake runners to gain access to the stuff underneath.

Anyone ever take off the intake stuff and dig under there? any things i should know before i proceed to take apart that whole side of my engine? (i really want to fix this!@@#@@#)

[240SXer]

How bad is yours?

[byroll01]

I had a very similar problem with both of my 1993's. I traced it down to my throttle position sensor. I cleaned my first one and it was a little better, stopped stalling. But I still got a surging and also a very unsteady idle(dropping almost enough to stall sometimes).So when it started happening on my current 240 I went straight to autozone and got a new TPS for $40. Problem solved.

just my $.02

byron

[p00t]

hmm i gotta check the TPS now? shesh...

How bad is my idle? My idle is pretty consistant when just sitting there, but anytime im doing stuff like braking it dips down to 500 always. It used to stall under braking/sitting at a light once in a while, but hasnt done it recently (knock on wood). I also have slight surging under acceleration.... sux. Car hauls *** and works great past 3k.... but ehh.. u know gas mileage aint too good if u keep it up there .

Im in the mood today/tomorrow to rip the intake off and clean that idle valve... im gonna be googling/searching for any walkthroughs in the meantime.

If anyone has done it b4 please give us a writeup or something!!@!

[240SXer]

So IAC/AAC valve and TPS.. I'll check out those two things. Seems like it's one of those problems.

[Nismo_Freak]

It's not gonna be the TPS if your getting a vacuum stall (IE brakes applied)

Now that I know that I can almost guarantee you it's the idle valve, also clean your auxillery valve.

A bad TPS will cause the ECU to idle hunt, as well as run poorly all over the RPM band cause it won't hit 100% WOT in this case.

[Nismo_Freak]

If you want to check your TPS signal do the following:

- Start Motor (allow to warm up, and let it idle) - Disconnect the electrical harness from the TPS- Check for resistance between the pins on the sensor

Specifications:

96-98 Model Years Idle - ~0.5 kilohmPartial Throttle - 0.5 - 4.0 kilohmsWOT - ~4.0 kilohms

95 Model YearIdle - ~1.0 kilohm Partial Throttle - 1.0 - 10.0 kilohmsWOT - ~10.0 kilohms

93-94 Model YearsIdle - ~2.0 kilohmsPartial Throttle - 2.0 - 10.0 kilohmsWOT - ~10.0 kilohms

* Steadily open the throttle and watch for spikes or drops in resistance. It should be a steady linear rise in resistance. If you find any spikes or drops then you need a new TPS.

[p00t]

k guys... i just completely removed my AIV and plugged all hoses, also scanned for intake leaks. no leaks were found but... wow my AIV was the cause of most of my troubles!!!! no more bogging idle! My brakes also feel more responsive/stiff now that the idle doesnt drop and the brake booster can function properly.

Very cool.

Reeds didnt seem too bad but did have alot of soot/carbon on them.

I am also going to clean idle valve when i have the time, clean throttle plate, and check the TPS. So basically what im trying to say is check the AIV first.

[s0ldats]

k guys... i just completely removed my AIV and plugged all hoses, also scanned for intake leaks. no leaks were found but... wow my AIV was the cause of most of my troubles!!!! no more bogging idle! My brakes also feel more responsive/stiff now that the idle doesnt drop and the brake booster can function properly.

Very cool.

Reeds didnt seem too bad but did have alot of soot/carbon on them.

I am also going to clean idle valve when i have the time, clean throttle plate, and check the TPS. So basically what im trying to say is check the AIV first.

you say aiv, is that the black box with the hose going to the airbox? or are you talking about the aicv which is under the intake mani.

[240SXer]

Can somone take a picture of this thing? can I just plug up the hoses like you did? Is there any advese effects with that?

[p00t]

ill do alittle write up for ya, let my camera recharge first

[240SXer]

Thank you very much...!

[p00t]

it got a sticky!! wewt!

http://www.nissaninfiniticlub....26150