okay guys newbie caddy owner here. my issues are: stumble upon take off followed by hesitation to accelerate. When I got the car the smog pump and hvac was bypassed, assuming both doesn't work.... keep getting e49 which is the air fault management. checked all vacuum lines, reading 19 on vacuum gauge drops to 14 when the throttle is pressed and doesn't go back up. we have replaced the water pump (unrelated) spark plugs with champion, and wires with oriellies cheapies, i'm running 100% gas 87 unleaded, tried changing seeing no difference. we have cleaned the t.b. (used carb cleaner) it's sparkling clean! not sure what is going on and i hope someone can help. it does okay on mpg 14-17 in city (stop and go traffic), but the stumble has me mystified. PLEASE HELP!!!
fyi its a 1990 fleetwood fwd with the 4.5.