Just purchased a used 1993 B2200 with 73,000 miles, all original, previous owner was a 70 year old gentleman. Everything is great other than the dreaded surge/bucking while accelerating in all gears that others on this forum have documented. I'll estimate the engine speed at 2500 rpm when it happens and you can push through it with more gas.

I've reset timing, changed fuel filter, accelerator pump squirting nicely, reset idle dwell 40-45 degrees, set idle speed, used carb cleaner, all hoses appear to be fine, just passed state emission test with flying colors, and o2 sensor fluctuating from 0.1-0.9v with 0.43v average while warm. Anything left or should I replace the mixture control solenoid? Is there a way to test it?

I have a link to a localdealer in the Seattle area that sells them. Assuming I buy the solenoid, who sellsthe upper carburetor gasket?

I'll post the outcome for others who have the same issue.

Thanks for any assistance.

 

My 91 mazda b2200 does the exact samething in all gears around 2500 rpms, not sure why it seems to be at the rpm. Seems like all these mazdas do this studdering,

 

That fact that it's at a consistent rpm and the idle is fine tells me it's most likely the carb. Anyone else care to chime in?

 

float level set to low ??

 

Amazing!! I wish I had an answer but yours problem reminded me of an 87 Dodge Dakota with a carbed 2.2 I bought new but have long been rid of it. It did exactly like yours. I always triedto accelerate smoothlyby slowly pressing the gas pedal but it would surge and buck like yours at a certain RPM then stop once past it. I never could figure it out. I guess I was expectedto floor it once moving? Could it be a defective throttle position sensor? Hope you figure it out. Good luck.

 

Well, I gave up and put on a Weber but in retrospect I should have tested the solenoid and replaced the o-rings since it costs next to nothing and may have solved the whole problem.

For anyone else with the same problem, checking the solenoid is pretty easy. Here's how:

Go ahead and pull off the top of the carb by removing about 8 screws around the top/side. Remove small e clip on linkage (I think it was the choke plate) so that you can lay the top on it's side. Be careful with the float, small piston to the side and the solenoid as you lift it up. Hook up 12v to solenoid and see if it clicks. If not, you already know that it's bad or clogged. Blow into it, with and without voltage to see if it restricts/prevents airflow as you apply/remove voltage.If it isn't working, try some carb cleaner to open it up. Assuming you get it to work, replace the o-rings (do it even if they look good). I found some at NAPA. Look at the jets to make sure none are visibly clogged. Oil the o-rings and piston sleeve then carefully put the top of the carb back on. If you have to push down much, the o-ring isn't seating and willprobably tear.Put in the screws and tighten them down. Check linkages to make sure none are binding. Don'tforget to put the microscopic e clip back on the linkage.

Shouldn't take more than a couple of hours and you'll save the headaches, cost and time of a Weber conversion. Or maybe not and you'll end up doing the Weber conversion anyway.