ok i have a 83 berlinetta Camaro with a stock 305. it has a Rochester carb on it. whenever i get on it she bogs out real bad. i have already changed the fuel filter and the fuel pump. However when i took the carb off and cleaned it it ran fine. but an hr later i went back out to drive and it was back to the sluggish beast she is..anyone know what i could try now???..lol anyone have this problem?

 

Does it backfire through the carb at all? This would indicate low fuel level in the bowl meaning the float is bad. Or it could be the air valve needs a little tension added.

 

It sounds like a float adjustment may be in order. I assume other things such as plugs and wires are in good shape. It could also be trash in the gas if she ran good when you cleaned it out and is now back to being a slug. Is the carb in good shape otherwise?

 

no the car does not backfire at all. and yes the carb is in great shape other than this problem.i have taken it off and rebuild it as well. still same problem? every time i take it off and put it back on it runs right for a while??

 

The prominent reason for q-jet bog is the air valve (secondary flap) opens to quick letting in too much air. When you rebuild/remove and replace the carb, have you adjusted the air valve tension? Maybe it is loosening up. If this is the original carb it could also be sucking air thru the primary throttle blade shaft as that is also a weak point on the q-jet. Just some of my experiences. Hope this helps.

 

i have not played with the tention and last night after playing with it, it seems that the secondary's arent opening?the plate lifts less than half way then sticks? blasted it with carb cleaner and still nothing? ima take it all apart and soak it for a day, i found some industrial carb cleaner and it says to soak for 24hrs.

thx man, and ill let you kno if it helps when i get the time to play with her.

 

Unless you are driving it, the secondaries should not open sitting still. Sounds like this is your problem.

 

Alot of times when q-jets get reassembled, the air horn screws get over tightened causing the air horn to distort. They are especially sensitive at the very back, and the air horn will protrude ever so slightly into the area where the air valve flaps have to pass. If there is any resistance at all, the air valve will not open enough to let in any fuel, but will let air, causing a bog. Examine the air horn to air valve flap clearance closeley. I usually file off the part of the airhorn that causes the interference.

 

ok, yesterday i was at my buddy's house and he has an old Rochester carb in his garage from his old camaro. we took mine off and put the old one on and the car still acts the same? it cant be the carb right? could it be the catalyic converter? maybe plugged? idk what it could even be now..... oh i also changed the TPS. hummm.....

 

An "old Rochester carb" would not be computer controlled like yours is.

Is your SES light coming on? If it is, read the codes that are being set and post them here.

A commonly over-looked item is the choke pull-off (called "vacuum break" by the factory). If it isn't functioning properly, it will allow the secondary air valve to open too quickly and "bog".

However, if your issue is general sluggishness, you've probably got something else wrong.

 

check engine light does not come on. its not generaly sluggish just when i push it to the floor. i got this info from Pony Carb's website.. does this sound like an option?

"The Quadrajet is a very wonderful carburetor. From the factory brand new, all one hundred and twenty million that we ever made had the following problems: They all had hesitations and flat spot on acceleration, a big bog on hard acceleration and hard starting when hot. "

Pony re-engineers the carburetors internally to take care of all these symptoms, and they run wonderfully when we get done. One note about an air valve secondary carburetor of which the Q- Jet is one, while we eliminate the bog on hard acceleration, the transfer of power when accelerating hard will still be a jerk when the secondaries open, not a smooth transition of power as a Holley Vacuum Secondary carburetor or as an Autolite 4100 performs.

 

Except "They all had hesitations and flat spot on acceleration, a big bog on hard acceleration and hard starting when hot" isn't true. If yours is doing that, it isn't adjusted properly, or a simple part (like the choke pull-off) has failed.

 

You said a few post back that it seems to stick half way open. check the gasket betwen intake n carb, I had a new one that dragged and did that. Had to pull the gasket n file it some. Was like a hair to small and when the back two opened up, it hung up.

 

the choke pull-off is a little piece of metal rod like 3-4in long on the side of the carb and goes from the secondary to a small pump looking thing?..lol sry dont know all the tec terms of carbs.. i tried removing this part cuz i thought it was the problem and still nothing. so i put it back on. seeing it is an air valve secondary carburetor could my air lalve be bad? or is that the choke pull-off?

 

My secondaries open w/engine running sitting still when I open throddle.

 

yeah i dont think that guy knows too much about what he said.. your secondary's should open when the car is started and you open the throttle. did he really think i had my wife drive it while i held on for dear life on top of the engine and checked it when she pushed on the gas??....lol hand/forehead!!!

 

It may be time to change out the factory timing chain. My '84 developed this problem and the last thing I looked at was the timing. Many of these came with a plastic coating on the cam sprocket to reduce noise. The coating breaks away and your left with a sloppy chain that tries to jump when you punch it. When enough of the coating makes its way to the oilpan you will start to notice that oil pressure is fine at start up but after the car warms up and you take a few corners the oilpressure drops off to almost the redline, the plastic will drain back out of the pickup when you shut down, then get sucked back up when you start driving around.

 

maybe you have real bad carbon build up

 

still no luck on fixing the problem... although i have noticed this. when i take corners and go over big bumps or railroad tracks fast it wants to stall? almost acts like it is out of fuel.then when the car levels back out its fine. still majorly sluggish. i don't have many tools and just cant afford to put it in the shop not even knowing what the problem is.

anyone in the Houston area? i could really use some personal help with this bothersome car before i sell it. i love the car and don't want to get rid of it. mainly because my b-day is in 83 and i love the Camaro.

 

Do you have any friends you could swap carbs out with to see if it truly is your carb that is the problem? Swap them out and drive it to see if the same issue is there. It's one way to eliminate some things.