I have a hypertech for my 1996 impala ss. I hook the programer and it tells me the vin number don't match. what is the problem how can I fix this problem.

look in glove compartment the ratio will be on that sticker in back of glove box

I don't think you have anything that will help in your search.
The 95 Impala SS came with a 350 cu in engine stock. The VIN code was P and the horsepower rating was 260. The casting number for that block would be something like 10199001 or 14101148. After 1970 GM started stamping a partial vin number on the blocks to match the original car. If you had the original car you could check the 8th digit of the VIN to verify the engine.

repace it its a common prob.

You basically have a engine ignition misfire this can consist of plug wires coil pack and sparkplugs,

take the vin number to dealer they can run it and tell you or give to me and i will run it thru vis and see build sheet

1996 impala ss - odometer light goes on and off - now it wont go on - would go in and out when when dimmer was moved. speedometer and odometer both worked and speeedometer still works - think is just the light?

Rotate the tensioner pully clockwise using a 13 mm 1/2" socket. (the tensioner pulley is the only one with a hex head bolt). Follow tthe routing guide inside your engine bay and replace the pulley. They can squeak from age even if they don't have any cracks.

$300 labor plus cost of part.. They will not warrenty the work if they don't diagnose the problem so plan on another $100 if you want then to gaurantee the fix.

on the fuel rail there will be a valve looks like a tire valve stem
remove the cap and install the pressure gauge

if after setting for a while will it re-start if so look at fuel pressure regulator chevrolet does not recomend but these are adjustable and will fix problem find good drivability person with gm background can fix you make some calls