even after my car is warmed up when the car is in park and i rev it up real quick it hesitates and bogs down for a second then revs up. when i start going from a stop real slow it feels like the car is jumping a very tinny from the rpms going up and down but its barley noticable but then when im crusing at around 1500-2000 rpms, or around 40-50 MPH the car really starts to shake from the RPM's going up and down. other than that the car feels fine at all other rpm's and when flooring it. Could this be something with gas or timing or mabey vacume leack? i have a modified motor but i still have the stock feul pump that i replaced about 2 years ago.


MOD's:
24# SVO injectors
edelbrock aluminim heads 60cc slightly milled
block bored .06 over
mild cam
feul pressure reg. set at 50psi
headers
timing set at 6* BTDC
I have an after market chip burnt for the modifications, nothing specila because i had it done over the internet from someone on this site

 

Hmm...You should get your fuel filter checked out. Possibly you pump. Does your fuel pump make a high pitched sound when its running? Maybe you have a Crank Positioning Sensor (CKP) OR Throttle Positioning Sensor (TPS) going bad? Seems like this can be related to alot other then just fuel, possibly vaccume leaks. I'm no expert here just trying to give you a few paths to run along with. Let us know what happens.

 

where is the crank positiong sensor?