91 S40sx Hesitation????
 

Just picked up a clean 91 240sx coupe. Im going to change everything, tune up wise. But i have a question first. When i give it gas it hesitates all the way threw the power band??
Ill check fuel filter and the jaco ignition that he put on..
Any thing else i need to know that need to be replaced?
160 thousand easy miles. Guy never went past 4000 rpm. Where do i shift at anyway. ANd im going r33 soon...
thanks..
jeff

I DID A SEARCH THANKS...

Well i changed fuel filter to 300ztt, new spark plugs, new rotor and cap, gas treatment, 91 octane, and it is better but still got hesitation. Ill change o2 sensor to. I think the aiv is still there looks unpluged but no plug? I have a jaco ignition and cold air..
No this is a problem with these cars...
thanks
jeff

also took out aiv, closed it up, cleaned injectors, cleaned mas flow, cleaned it all up.. still got bad hesitation when full throttle. Im going to change fuel pump with 255 walbro for my next engine anyway.. Just cant get the thing strait yet. ???
jeff

duz adding a cold air intake cause problems for the mas air flow sensor?
I got 3 codes..
12
32
34
didnt before i cleaned it, now after i cleaned and gave it a tune up i get engine codes...??
jeff

i would say try it without the jacobs ignition... return it to stock and then see what happens from there if the hesitation goes away it is in the module... they have a life time warentee so send it in if it is the problem...

i mean hesitation like u floor it and it takes a sec for the engine to rev??

i mean u mean in my last post type-o i get alot of those

I took the jacobs system out, it wasnt even installed completely..lol
I got 4 codes. 11 , 12 , 32 , 34
crank sensor
egr
knock sensor
mag sensor

When i give it half gas it goes somewhat ok, when i give it full throttle it bogs down and jerks like as if it was in safe mode. But i can rev past 2500.. All those sensors are $$$. And im going to do a swap. Its kinda a like my honda with a swap all kinds of codes i installed new sensors and bingo hell fast and no check lights..
thanks
jeff

SO i installed the new maf and found a leak at a hose on the egr. No more codes.
Time to go turbo..
jeff

Figured out my hesitation.. Fuel Pump!!! Got a whalbro 255.. Boom pow!! no more problems. And super fast..
jeff