what would cause the same symptoms as a clogged fuel filter

[84 delta 88]

hey guys ive got a 84 delta 88 307 with the factory ccc Qjet I took the carb off about a week ago to install bushings in the primary throttle shaft I also tried to put a new tps in while I was there but I broke it and had to put the old one back in. ever since its had an issue with surging at wot and it falls on its face from a dead stop like its not getting enough fuel ive already changed the filter with no luck what does this sound like to yall I'm leaning towards the float level being wrong, could the crappy old tps have something to do with it?

 

[Texas82GP]

Did you calibrate the TPS when you reinstalled it? I'm working on memory and don't have time to look it up right now but the way I remember it you have to connect a Digital multi-meter to the TPS and calibrate it to a certain voltage with an adjustment screw. Otherwise, did you use a new gasket in the top of the carb? They are easy to tear and it could be leaking vacuum there.

 

[84 delta 88]

I had to put the old one back in so no I didn't calibrate it, I don't have any vacuum leaks it just acts like its not getting enough fuel

 

[Texas82GP]

Feedback from the TPS is utilized by the ECM to control enrichment through the Mixture Control Solenoid. Since you disturbed it, you may well need to confirm the TPS calibration. Are you getting any codes? Are you sure there is no way you could be leaking vacuum between the carb's top and main body? That would cause a lean condition.

 

[theoldsone]

Same thing happened to my 307. I practically worked around the problem until I replaced the carb. Filter, Fuel pump and Timing chain. Pulled one out of a Lesabre and it ran just fine. Changed out the secondary metering rods and hangers for the one that were on the original 442 carb and added some timing into it,Timing chain should be replaced too if it's passed 100k. Trying to "rebuild" a ccc Q Jet is a task. If you can get your hands on a localy used one then do it.

Sounds crazy but if your running a 200r4 check and see if the tcc is stuck, just disconnect the plug underneath and drive it. see if that changes anything.

 

[oldsmobile joe]

low float level, low fuel pressure or insufficient capacity, would feel like a clogged fuel filter. fuel pressure should be about 5-6 psi and it should pump a good amount of gas, like a soda bottle worth in 15-20 seconds of cranking. if these tests fail, look at fuel pump, fuel sock in fuel tank, or a pinched/collapsed fuel line or hose.
i base this response based on your info, surging at wot. the falling flat on its face, is usually insufficient fuel caused be lack of fuel for the accelerator pump to shoot in to the motor or the rubber cup on the accelerator pump is bad. both of these conditions are outside the control of the computer controlled adjustments of the carb.
while its been 25 years since i messed with one of these carbs, when i worked for the chevy dealer, i overhauled several dozen of the quadrajets while there. there are several members who are well verse in these matters and hopefully they will join us in helping you out.

 

[84 delta 88]

well its been a while but since my last post ive checked the fuel sock in the tank every inch of line and replaced the pump to no avail ive installed a new tps and have ordered a tool to adjust it ill see if that helps, could this possibly be timing or carbon buildup on the back of the valves also when I had the carb off last I removed the egr discharge tubes from the primary bores could this be part of it I'm really stumped at this point

 

[pontiacgp]

Sounds like the secondary air doors are not adjusted properly or they are locked. It's dumping fuel when flooring the pedal and if the air doors are not opening your going to a rich condition causing it to bog.

 

[fastSS]

check the secondary butterfly tension it is adjustable. this is not my video lol.

 

[84 delta 88]

the secondarys are opening, for the first 3 or 4 seconds of wot the car takes off then it starts surging