: northstar rough accleration/idle

03-16-06, 03:05 PM
i did a search on this problem. but i still have a few questions.

here is this scenario. i have a 1996 sts with 143k, bought it at 133k. owner said that the plugs were changed, dont remember if he said wires changed, they look like they are but who knows.

when i accelerate from a stop the engine seems to accelerate then decellerate and it goes back and forth like that. then eventually smooths out. also while idling at stop lights every once and awhile youll feel a thud, more than normal and the idle is around 600 normally around 750. also at idle it seems like its gonna stall from the rough idle and lower rpm.

i was thinking either the fuel filter or plugs/wires? any ideas? i know the fuel filter is significantly less expensive than a set of ac delco wires and plugs. if you guys think it is the fuel filter, can someone write a quick guide on to change it? as for the wires and plugs my father did his on his 94 concours so i can ask him.

03-17-06, 04:01 AM
my deville idles a 625 to 650. but i would put new plugs in it that fixed my rough idle. the fuel filter is easy and probably cheap wouldnt hurt to do. if the plugs dont fix it you can do plug wires also.

03-17-06, 04:44 AM
A restricted fuel filter should show up at high RPM rather than idle. A lot more fuel has to go through the filter at high RPM.

I'd start with delco plugs and wires.