Toyota 87 pickup
22r engine
197,000 miles
w/ Weber carburetor 32/ 36 with manual choke

hard to start, both cold and after driving for hours. in order to start one person has to put hand over butterfly flaps in the carb. we got a new choke and that solved the issue for a while, but it is now hard to start again. it has a rough turn over but often does not start.

while driving on highways when shifting into 3rd it lags / stutters / hesitates . . . heard a "pop pop pop pop" while trying to accelerate from onramp to highway today.

just checked / replaced

- fuel filter
- spark plugs & wires
-rotor
-distributor cap
-choke
-valve adjustment
- timing adjusted and the carb pin adjusted.

6 mo ago carb tune-up : summer time @ 7300ft altitude (not sure if that is the issue but relevant to note)

this week carb adjustment : october (cold mornings) sea level

I am assuming it is a fuel / air ratio problem, but not sure how to fix it. might be something else. any ideas what to check next?


thanks for the help.