WS62000

iTrader: (21)

There is a hesitation in my engine when I accelerate at about 1/2 throtle. It is from about 1800 to 2300 rpm. You can feel the car jolt when you hit the gas, and hesitate to go? The rpms don't drop down or anything, but it feels like they do. This doesn't happen under light acceleration or full throttle? What could this be? I'm getting a cam installed soon (with new springs/pushrods/new plugs and wires and a tune), do you think this can solve the problem? I know it's not the clutch.

Thanks

ArcticZ28

iTrader: (14)

The tune that you should get thereafter the cam swap should take care of it.

prostock_bigblock

iTrader: (11)

ya probably have one of 2 problems:

1- need a tune-up
2- fuel pump.

WS62000

iTrader: (21)

I forgot about the fuel pump. Should I just wait until after the tune, or should I do a fuel pump at the same time?

prostock_bigblock

iTrader: (11)

if u r doing it now or later on , just do it with the tune-up.

WS62000

iTrader: (21)

yeah, I will probably do that then.

Thanks for the help

ArcticZ28

iTrader: (14)

why would it be the fuel pump if it only cuts out at half throttle but not WOT?

BULLET99Z28

iTrader: (9)

My car did that a while back. i thought I ran out of gas. Shaner told me to check the front O2's. SO I swapped the fule filter,added some lucas cleaner and replaced both front sensors. I had water in the left front O2 connector(car has headers, I guess I sprayed the bottom the car to hard when I cleaned undr the rockers). I simply used the rear 02sensors from the ory pipe swap. the car has worked fine ever since.

prostock_bigblock

iTrader: (11)

Ok .. u really dont need to loose extra money with replacing everything while one part is making the problem .

i would suggest checking th O2`s at the beganing.However, I really doubt if it is spark plugs or wires . it doesn`t make sense to hesitate on 1/2 throttle and on high rpm not. Change the fuel filter it doesnt cost more than 7$ .

I used to have the same problem and it was the fuel pump ... but yours could be not.

orangeapeel

iTrader: (18)

Now are you getting bad gas mileage on top of this?
FWIW I had a similar problem and swapped the plugs and checked the O2's and it went away. Still have original stock fuel pump and injectors. this happened after my last cam swap from a 222/226 to the 244/248. I have stock gears so that was what I thought that the hesitation was coming from. I went from 14.7 avg mpg back up to 21 after I did the above.

WS62000

iTrader: (21)

I'm getting normal gas mileage, better than my auto formula

Clark Kent

same thing was happening to me for 3 months until i replaced my crankshaft sensor and fuel pump, now nothing happens it is fine. im almost sure it was the fuel pump.

WS62000

iTrader: (21)

Well, I replaced the spark plugs, wires and went to get it tuned but it can't be tuned because after the cam/header/intake install the hesitation got worse.? My car is throwing some codes - they were there before the install of everything. What else can it be? Coil pack? I don't think it's the feul pump because this only happens like 60% of the time, and only at the rpms I mentioned
Help!

vert_vette

cheapest thing first

try Shell V-Power super unleaded

fixed my hesitation

WS62000

iTrader: (21)

I'll try...

any other suggestions?

10secopcar

u might check your maf. my car got way bad about hesitating when u try to give it throttle. but i live on a dirt road and between the oil from the filter and the dirt i had quite a bit of build up on my maf sensor. easy to look at and c if it dirty just a suggestion

WS62000

iTrader: (21)

Well, it still hesitates bad. My fuel pressure is fine, new plugs and wires and O2 sensors, no air leaks anywhere after the MAF, which is clean. It was being diagnosed in a shop for three days and after reading the codes and looking it over, they couldn't find anything wrong that could cause this.
What should I start replacing to get this car to run right? It hasn't been dyno tuned and can't until I fix this, so right now it's running like crap!
Please help!!

Mr. Luos

iTrader: (9)

What codes?

WS62000

iTrader: (21)

I'm not sure, they deleted them after checking them all and finding out if it would fix the problem. I guess none of the codes shown were connected to the problem? But I don't know. I can call the shop on Monday to see what codes were being thrown.

Mr. Luos

iTrader: (9)

Vacuum leak?