KA sputtering at 4000 rpm!!

[matysik27]

I've got a 1991 240 with a dohc ka and just freshly rebuilt with new internals. Now the only problem is that it hesitates to start and pops and spits from 1000 to 1500 rpm then smooths out fine until 4000 then sputters and wont go higher than 4000 rpm unless you feather the throttle. Anyone know what could be wrong?

The only thing not stock would be that i have a Z32 mass air flow sensor

[matysik27]

anyone at all?

[Bigsyke]

Code 34? Knock sensor bad.

Disconnect subharness and stuck a 1megaohm resistor in there, it should smooth out past 4k.

Z32 mafs? Dont you need a tune for that?

[matysik27]

Code 34? Knock sensor bad.

Disconnect subharness and stuck a 1megaohm resistor in there, it should smooth out past 4k.

Z32 mafs? Dont you need a tune for that?

it was doing this even when i had my stock MAF too though. i switched thinking this would solve the problem and now nothing has changed

[Felipe]

is your check engine light on

[matysik27]

is your check engine light on
nope hasnt been on at all

[Bigsyke]

again man pul the codes, check for the KS code

[irax]

it was doing this even when i had my stock MAF too though. i switched thinking this would solve the problem and now nothing has changed

soo... wait.. if you have a stock maf and it did this with the stock maf why did you 'upgrade' to the z32? doesnt make sense. I would of solved the problem first.

Is the dist. new, rebuilt, or old? did you test the injectors? did you test the signal to the tps?

[matysik27]

soo... wait.. if you have a stock maf and it did this with the stock maf why did you 'upgrade' to the z32? doesnt make sense. I would of solved the problem first.

Is the dist. new, rebuilt, or old? did you test the injectors? did you test the signal to the tps?

because i had it laying around and thought this might solve the problem. injectors test fine and didnt test the tps.

[matysik27]

ill try to pull the codes. the ka can run without a knock sensor right?

[matysik27]

i pulled code 55

[FWD LOL]

im suprised the car even runs with that MAF. you need to get a tune or an afc to calibrate that maf- clean the stock one and put it back on- you dont need a 300zx unit unless you are making better than 260hp. which you wont do without a turbo/ forced induction.

[matysik27]

im suprised the car even runs with that MAF. you need to get a tune or an afc to calibrate that maf- clean the stock one and put it back on- you dont need a 300zx unit unless you are making better than 260hp. which you wont do without a turbo/ forced induction.


got a new stock MAF and now it runs butters. thanks for all the fast responses

[irax]

did you look up what code 55 was? do you need an fsm?

[matysik27]

did you look up what code 55 was? do you need an fsm?

code 55 means there are no codes to be viewed

[CrazyKoukiS14]

i had the same problem, get a tune up done on your car and you should be fine, my problem was my spark plug wires, get some NGK's and its smooth sailing from there

[matysik27]

i had the same problem, get a tune up done on your car and you should be fine, my problem was my spark plug wires, get some NGK's and its smooth sailing from there

everything was brand new so it already "had" a tuneup. anyways i got a new stock MAF and it runs fine now so thanks anyways though.

[CrazyKoukiS14]

yup no problem