OK... we have a 2002 Chevrolet Impala LS with the 3.8L 3800 Series II engine. About six months ago the catalytic converter went to hell and now is no longer existent (A straight pipe is now where it was). About two months ago, we noticed that once in a great while the car would chug when accelerating from a slow speed, like after you make a turn, or seemed to "miss" for a few seconds when at cruising speed. This has progressively gotten worse to the point of the engine quitting while going down the road or idling at times and to allowing no acceleration after slowing to turn. We replaced first the inline fuel filter. Not the problem. Then we replaced the fuel pump. Again, not the problem. (Thank God we don't have to take it in and pay labor!) Now, we hooked it up to one of those little handheld portable code diagnostic computers and it came back with "MAF/VAF" (in this case it's MAF), "O2 sensor bank one low input" and "catalytic efficiency" (which I'm guessing is because there is no catalytic converter. Anyhow, these are not exactly cheap sensors and I was wondering what thoughts might be on most likely culprit. I also was thinking that it could be a throttle positioning sensor? That's just my thought. Another symptom that I am not sure is related (doubtful) is that sometimes (maybe 1 in 25 starts) you have to hold the key in the start position for a couple seconds (once it was almost 7 seconds) before it even engaged the starter to turn over. As I said, I think this is separate and I know we are supposed to list two problems in two places, but if it's possible that an ignition could be causing all of this I wanted to mention it here too.

OK FOR ONE I GOT THIS CAR AND GOT A CAR LOAN FOR THIS PIECE OF SH*T. FOR ONE, WHEN I GO TO 45 IT SHAKES BUT ONLY IF YOU DRIVE IT FOR A WHILE. I WAS TOLD IT'S A WHEEL BEARING. WAIT THERE'S MORE, IT'S BEEN LEAKING WATER AFTER I SHUT IT OFF AND IT SITS AWHILE. ALSO WHEN I PUT IT IN GEAR LIKE REVERSE YOU CAN FEEL THE ENGINE SHAKE. I HAD SOMEONE SIT IN MY CAR AND PUT IT IN GEAR AND IT LOOKED LIKE THE ENGINE FALLS BACK. I WAS TOLD IT'S THE MOTOR MOUNT. HMM HAD IT LOOKED. AT GUESS WHAT? IT'S NOT BAD. YA IT KINDA LIKE MAKES A CLANK NOISE WHEN I PUT IT IN GEAR. WTF. PAYING ON THIS CAR UNTIL 2014 AND NEEDS A LOT OF WORK. SO LET ME KNOW WHAT U GUYS THINK THIS IT COULD BE.

Car would stall while driving,and would not start right away,had to keep cranking it and eventually it would start,brought to chevy dealer and control module, battery, ignition coil,and crank sensor were all replaced nothing worked. Last week it got to the point that it would not turn over when trying to start, and yesterday it went completely dead, will not jump and when jumpers are connected there is no power. Was told by chevy dealer I should trade the car in. Car only has 26000 miles on it and was always garaged looks like its in excellent shape, I would like to be able to get it fixed.