hi , i have a chevy cavalier 2.2 lt 1998 auto.

it burns fuel like a log. will do only around 11 miles per galon,, the tps sensor was bad, the iac valve and the map sensor.

rough starts .changed the spark plugs, plug cables, changed the coils , it still has a misfire on cil 2. but its intermitent. , probably a bad new coil,,still has a rough start and have to push the gas to start, no fuel leaks, no smell,

tps fault., scanned that , changed that,, , trasmission working fine.

wondering if rough start is electric,, still has original ignitition module.. havent tested it..
or ckp sensor about to go , what to change first if needed.?

but my scan tool only gives me a “count”reading for the ckp and cmp sensors , any idea what it means?

by the way the timig chain also changed new. , the tensioner was about to give in.,
i still have to press the gas to get it to start,, crank is fine.

noticeable findings,

fuel cell trim, at 21 ate idle.
it will go to 0 on acceleration or cruise or the ac on.. (which is strange)
thought it was the map sensor,, or a vaccum leak,, but no.

short trim and long term trim are at 0, doesnt make sense with a fuel cell trim of 21,, or the model just doesnt support short and long trim values

the fuel burn is really serious.

i suspect the ignition module might be faulty .

this car is rated at 23mpg, but its doing 11 mpg .

really need help with the fuel problem, any ideas are welcome.