I just purchased a 90 Formula 305TBI, the car has 154k miles on it. I have a wrecked 305TBI 89 Formula with 84k miles on it with perfect engine and tranny. Now the fuel gauge does not work on the 90 and my guess is the fuel tanks needs to be dropped and swapped. I'm guessing the cars poor running condition lies in the fuel system, so we'll change filters, swap tanks and check TBI. We are also going to swap exhaust from the 89 to 90. Since the 90 has a gutted cat and a hole the size of a baseball in the muffler. And I have American Thunder Flowmasters on my 89 . But anyway back on subject, any other things I should check for the cars poor throttle response, actually its more like press the gas and hope it moves. The car about stalled on me in an intersection driving it home. Also where could I get the list of 89 ECM Trouble Codes? Thanks for any info, heres a picture of the new car.

 

Hey good lookin car. There are lots of things that can cause your sputtering. Something as simple as a clogged fuel filter can cause a car to idle but not run under load. When was the last time the car had a tune-up? I would start with that. These cars get neglected over the years and it could have all of its origonal plugs and wires. I would trace the wires to make sure that they are not cracked or burnt through either. A good ol' fashon tune up goes a long way on these cars.