tacoma missing out

have a 97 tacoma 4X4 3.4L engine 5 speed. 139,000 miles. problem is whenever i accelerate the engine misses out. if i ease up on the gas it will lessen. when getting to highway speed it runs fine but slight inclines where the engine works harder it misses out badly. put some heet and injector cleaner in, no improvement. now today driving into town the check engine light came on. no clue as to what is going on. what do you think people?

itchy

Have you changed the spark plugs? If not that's a good place to start. If the air cleaner hasn't been changed or serviced recently it may be a good idea to service or change it. If the truck runs OK after these services and the check engine light is still on you should be able to cancel the code by removing the EFI fuse for at least 10 seconds.

Clifton

Get the codes from the ECM.