I need some suggestions

I bought a 93 b2600i that needs a lil motor work. The guy I bought it from took it to about 4 different mechanics and replaced basically the whole fuel system, distributor cap, plugs and wires and the MAF sensor and then sold it because he didnt wanna mess with it anymore. The problem he was having was that when he tried to drive it the would sputter and not rev up but I think Ive narrowed that down to just being from a weak battery. Since ive gotten it ive gone through about a quarter tank of gas with no problems as long as the battery is charged. But when its sitting and you rev it up it revs up fine but when you let off the gas it goes down to about 500 rpm and sounds like its flooding itself out for a second and then goes back up to about 800rpm and idles fine. Now the MAF was just sitting on the fenderwell as you can see in the picture. Ive since thrown an old air filter from my quad onto the end of it but its to big and doesnt fit around the end properly and now it only tries to die out sometimes. So my question is do you think if the right size air filter was put on it would stop this or is it just a coincidence? Also the check engine light is on. Do you think that its on from the MAF just sitting there and getting to much air from it being open? If it would help I could get a vid of it running and it trying to die out if anyone wants. Thanks in advance for the help and sorry for the long read

Could be lots of things but you have a great clue with the CEL. Pull that code and get back to us. Filter won't make a difference.

What do you mean when you say pull the code? Take it to a shop and have them plug it in and find out what error code its throwing?

BINGO, if the cel is on that is the fastest way to get at least a good direction to look in, if not the exact problem

If u do not have an air box with a filter on it the MAF is going to raed all that o2 coming in and try and compensate for a mixture that appears way off,thus the sputtering and running poorly.Put the proper airbox and filter in it and I bet ur poor running problem ends.It is setting a "lean code" and that is why ur lite is on.BJ

Ok that was my first thought, that was why I just threw the filter on it to see if it would make a difference. Can somebody get me a picture of what the airbox should look like, as it didnt come wit one and I dont have another truck I can swap it from. If this doesnt change anything Ill take it somewhere and have it checked out. Thanks for the help

I have seen many mazdas with high flow cones, and no airbox with no CEL....the MAF should read the incoming air and adjust the fuel supply accordingly, along with the O2 sensor and temperatur sensor....You could try putting a box on it, but I doubt, that will remedy your situation 100 percent. it is still bes to either get the code read at a shop, or get a scanner and do it yourself.

Right, the MAF measures Mass Air Flow. The airflow through the engine and MAF will be the same regardless of the air filter.
If you have an autozone nearby, they will get the code for free. My money is on the MAF itself.

FYI, autozone doesn't read pre-'96 import codes, they barely read OBD1 on anything, they pretty much do as they please which is almost always OBD2 only. The air filter wont make a difference. It is possible the MAF got dirty being used with no filter, and therefore causing problems. Guys are right, get the check engine light checked first before anything. BTW, it also looks like the hose clamps are missing off the intake tube right by the throttle body, you need to have a good seal, you should make sure they are clamped tight... L8RS!

i say, ditch the stock setup, and go with a cold air intake, we'll take it to the shop over thanksgivin break, and see what vinney has to say.