I have posted before about my low gas mileage that I get from my 2004 Impala Ls. I had 2 codes on the car, got sick of guessing what it could be so I took it to the dealership. Fixed the lge emm. leak, ended up being a vent valve above the gas tank. I have been having misfires in the engine. Dealership said this was due to a lower intake gasket(upper plenium) leak. when i took it to Autozone it said a Cyl. 6 misfire. i hope the dealership isn't tryin to get a "job" from me. Can the Autozone scan be wrong or is this all the same part anyway? $880 for it to be fixed. I know someone who can do it at less than half the price, but where can I get the part? Dealership wanted too much. And last but not least, can this intake gasket be the source of my low gas mileage? 176 miles now to a full tank, filling up @ around 15 gal.s Thanks for any info. given

 

Intake gasket has been a problem in ALL of the 3100-3400-3800 cars.

 

Car fixed today, way cheaper than dealership quote!!!!!!! $182 for parts, $150 for kid down the street to fix it. BUT the car still does a little jerking like it's starving for gas. Don't get me wrong HUGE diff. in the running and sound of the car. He was gonna change the fuel filter but he couldn't get the old one off.(stuck I guess). I'm not sure if it has ever been changed to be honest. Is there any other small parts that I should change that should be changed? It has 128,000 miles now. I have always had brand new cars and all of this is such a pain for me, please let me know.(:

 

I'd say changing the fuel filter is a must, but you may need to take it to a facility where they can repair nylon fuel lines if required. It takes some expensive specialty tools to do it right.