acceleration problem
 

i have a 90 GXL with a new cat. and fuel filter. everytime i floor it, she sputters and does not accelerate, but keeps going the same speed. what could be the problem? thanks

what rpm does it stop at or does this... be specific... could be 3800 rpm hesitation.. if so try regrounding the car... thats what im doing right now

TPS, bad electrical grounds, fouled plugs, leaky injectors. Try checking out the 2nd Gen FAQ.

it's not the 3800 hes. it's only when i floor it. i can ease into it and it runs fine. TPS is fine, checked already. i guess i could check the grounds and plugs. anymore help would be great.

The TPS may be perfect at idle, but what about part way out (like when you're accelerating)?
Pull the TPS plug, clip a meter on the orange & green wires, look for an ohms drop further out in the plunger stroke.

The TPS may be perfect at idle, but what about part way out (like when you're accelerating)?
Pull the TPS plug, clip a meter on the orange & green wires, look for an ohms drop further out in the plunger stroke.

i've tested that already. closed and open throttle. i have the FSM, but it does not have my particular problem listed. on top of all that, my gas mileage really really sucks. i've put a full tank in and have gone 156 miles and now it's empty. this really blows...

found the problem... the auxilary ports in the engine were not opening due to the shafts being locked up from carbon and such, the gas mileage was bad because the intake manifold was not tightened up. thanks for all the help.

i just thought all my problems were fixed. i've done so much it's hard to start somewhere. it's still messsin up. I have no acceleration only when flooring it, TPS is ok, poor gas mileage, sounds like there is a leak of some sort after flooring it, accelerates fine when easing into the throttle, new fuel filter, cat. con. ok. ran fuel injector cleaner already. i've replaced the hoses, checked the acc. cable mount, and it doesn't smoke. i'm starting to think that it has something to do with the fuel and something controlling it. it might even be that the fuel filter clogged up again seeing that i put cleaner into the tank. well i've replaced the spark plugs, wires , and checked the secondary actuator and auxiliary ports and they're working fine. when i floor it the sound i hear is like a fffffff. if i cut off the key, floor the pedal, and turn the key back on, the car takes off and then after a few seconds the hesitation kicks back in. it sounds like there is a major vacuum leak but i've replaced the hoses and they're all fine. could it be an apex seal or other seal has blown? i readjusted the tps yesterday but still no luck, does anyone have anymore clues? i will replace the fuel filter again this weekend but would also like to check other things as well. anymore help would be great. thanks

check the water thermo sensor?

i too have a 1990 2nd gen and it does the same thing every once in a while. it seems like i will get a small kick then it just goes then kicks again. i have the mazda speed intake and hks exhaust so i have high flow i just know waht going on?

i know that the water thermo sensor detects water temp but how would that affect the performance and if i do check it, how would i take it out to check it, without removing the intake? need... more... help..., must... go... fas..ter.... thanks

well nevermind about all this. the person before i owned the car cut the clock light and tapped that wire into the check engine light for some reason therefore i never got any error codes. Now i have error codes and i'm checking all the "situations" out and playing elimination. I got codes 12, 13, 17, 27. My TPS reads ok and the pressure sensor i'm checking this weekend along with the MOP. the O2 sensor also doesn't read correctly so i'm replacing that also. hopefully that might fix the problem, but if not i have three other alternatives. thanks for all your help though peps.

i have the same problem. i've notived that i have no boost while easing it in and if i go to floor it, it jumps from the negatives to zero and stays there. the other thing i noticed, on my air fuel meter, it goes from running rich while easing to extremely lean when it hesitates. i just got the car and the previous owner said that i had to reground the secondary injectors. but im not sure if he's talking out of his ass or not