No power at part throttle, carb edition

[Howlite]

Hello, this problem has been bugging me for the past month, ive got a barebone 88 dx accord that doesn't have ecu.
When pressing the gas pedal at a certain point i completely lose all power, and a faint sound can be heard, almost like it's misfiring, at this point if i press the pedal all the way it goes away.
The car does not drive as it used to, it feels way weaker than before.
The last two things i worked on were a distributor inner oil seal change and valve stem seal replacement.
I tried changing both fuel filters, spark plugs and i tried re adjusting the carb (stop screw, idle screw and especially af mixture screw)
The carb was rebuilt a few months ago.
I am at a loss, any help would be appreciated.

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[ShiRen]

Actually, it does have an ECU, it's just dumb as rocks.

Sounds like it's leaning out when the secondaries open. I expect a vacuum leak somewhere and it is unable to blend the throttles blades with the right amount of fuel. The way to fix this with the vacuum delete is just bending the accelerator pump tab, which you could do I guess.

[Howlite]

Actually, it does have an ECU, it's just dumb as rocks.

Sounds like it's leaning out when the secondaries open. I expect a vacuum leak somewhere and it is unable to blend the throttles blades with the right amount of fuel. The way to fix this with the vacuum delete is just bending the accelerator pump tab, which you could do I guess.

Update,
Yesterday i changed the pcv valve, checked distributor cap and rotor and reset af mixture but the issue was not fixed, today i noticed the car had a very bad misfire, after looking around i found out cylinder 4 spark plug was not firing, so i pulled out and cleaned all 4 spark plugs, cylinder 1 and 4 spark plugs had oil residue on them (seems like i did a really bad job on those valve stem seals).
I also checked for any vacuum leaks with carb cleaner but couldn't find any.
Lastly i redid my af mixture using a vacuum gauge this time.
Now the car jerks on throttle, it feels like the same thing happens as before but for a split second.
I am guessing the spark plugs are the problem as they are getting dirty, but wouldn't cleaning them fix the issue temporarily. Any ideas?

PS.
accelerator pump works and the tab is bend as specified in the manual

https://www.dropbox.com/scl/fi/1myfs...=qz9yarv1&dl=0

[Oldblueaccord]

Change out those plugs for fresh NGK's coppers gapped at .030. See what that does for you. Sounds like you got 2 cylinders using alot of oil.

Idle mixture screws are just that for idle mix nothing else.

[Howlite]

Change out those plugs for fresh NGK's coppers gapped at .030. See what that does for you. Sounds like you got 2 cylinders using alot of oil.

Idle mixture screws are just that for idle mix nothing else.

Gapped at .039 or actually .030?


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[Oldblueaccord]

Gapped at .039 or actually .030?


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I always go smaller gap not bigger. Less chance of misfires. Esp if you having and oil consumption problem.

[ShiRen]

Heck mine might be gapped near .02" I had a lot of issues with the spark not being adequate on this car. I run an msd box now and it made a world of difference, it's an old 6a unit I got off eBay for $50. Another big upgrade is the coil itself, but check the resistance of the windings, it may very well be bad, if it is you might as well swap it out for an off the shelf performance coil like an msd or accel coil.

Again, check the operation of the accel pump, a little jet should squirt from the back side near the top of the carb opening when you hit the gas, if not it's broken and needs to be fixed, and bending the tab slightly still might help it a bit if it's working. I believe I have some information on it on the vacuum delete thread

[Howlite]

Update
It took me a while because i had to remove the cylinder head in order to change valve stem seals to fix the oil issue.
I tried setting the gap to 0.03 but the same issue persists.
I also tried bending the accel pump tab in closer to the stop, so that it adds less fuel but still it didnt fix the issue.

After doing the valve stem seals, both the starter and the distributor decided to shit the bed, the starter randomly stops working and the distributor is making a faint sound and the tech sometimes jumps on idle, after fixing those ill check the fuel pump.

I also noticed that the spark plugs have white spots on them which indicates that its running lean, could this be why it loses power mid throttle ?

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[ShiRen]

You want more fuel not less fuel, the accel pump is pretty conservative

Yeah being lean will cause it. Check for vacuum leaks. Carb base gasket for sure