93 Carb. B2200 intermitent missfire/shutting off.

Ok, First off, I have been lerking here as a nonmember for a while. This place has answered so many questions for me and for that i am truly gratefull. My problem is that I have not been able to resolve my issue, so I finally joined and am asking for the same great advice that you guys always seem to provide!

The truck is a 93 B2200 Carbureted. 144,xxx miles. I bought the truck in non running condition for a good deal. After playing with it and replacing the basics and doing a compresion test. Plugs, Wires, Cap, Rotor, Fuel filter, fuel pump, I finally got the truck to start. I drove it about 3 miles and it had an intermittent skip. Mainly under a load. After about 3 miles the truck died, and would not start back. This is with the factory carb. I am new to carburetors and had read horror stories about trying to adjust the stock Mikuni. So I replaced it with a brand new Weber 32/36 DGEV. After some adjusting and playing around with that, I got the truck started and it ran great. For about 2 weeks. Then all the original symptoms came back.

Now knowing that the fuel system and carb are new i decided to look at the mechanical timing. I tore the front of the engine off and the timing was dead on. However the belt was stretched significantly. I replaced the belt and both pullies. After the belt changed i made sure the distributoor was indexed properly to 9 oclock at TDC. After this the truck started, i set the base ignition timing to 6 degrees BTDC. The truck still had a small skip under load. Simply because parts are cheap, i changed the coil at this point and the problem continues.

Now i have all these new parts and still cant get this thing to run right. I purchased a new pickup coil and ignition control module. No change. After some more research here, I learned that lots of the short nose mazda engines, including ours, is somewhat plagued with keyway ware on the crank. So yesterday, i completley pulled the timing compnents back off, removed the crank bolt, and the key way is unharmed. I once again made sure it was put back together in perfect timing and the distributor is indexed properly. The truck started, I made it 1/4 mile down the road with 0 skips and the truck just shut shuts off. I pulled it home using the wifes Envoy. I made sure the timing belt didn't eat itself, and that it was still in time. I also checked to make sure that the coil has 12v+ at the coil with the key on run. all checked out ok.

I am completley stumped. Can anyone please help get this thing running. If i cant get this thing running soon then I'm just going to do the Kia FE3 swap and be done with it. Thanks in advance!!!!!!!!!

P.S. sorry for the book, just wanted to make sure that you all know what i have changed.

You could have a bad ignition switch. If so, when it decides to cut out, it will kill power to the coil, but can still show power at the coil when it cools off. I'd double check power to the coil at the time of your stall, and possibly keep a jumper wire on hand, so you can jump the coil and get back home... if that's indeed the problem.

Thanks for the reply! Today when I got home I tried running a jumper wire from the battery straight to the coil and it still wouldn't start. However the battery was near drained, so I'll try again tomorrow after the battery charges.

There is a 14mm bolt in the bottom of the gas tank. Put a catch pan under the tank and drain some fuel into the pan and inspect it for a blob of water. You may have replaced the fuel filter but maybe there is enough water in the tank to have ruined the filter you replaced.

or there could be crap in the fuel tank like rust, clogging your new fuel filter...

So after getting several recommendations for inspecting the fuel system, When the weather clears up a bit, I will be dropping the fuel tank, cleaning it and the fuel lines, replacing the new fuel filter again. And giving it a shot. I'll let you know own how it goes! Thanks for the help.

You are making a lot of extra work on this. Take the new fuel filter off and empty it into a glass container and look for a water blob. That will give you a clue as to whether water has contaminated the fuel system. If it has, use the 14mm bolt in the bottom of the tank to drain about a half a gallon from the tank. If that is the gas, put about 3 gans of dry gas (alcohol) in the tank and you should be good to go. Replace the fuel filter.

So today after work I drained 1 gallonish of gas and checked for water. There was none. So I started checking things that have already been replaced. I determined that there was a good spark from the coil to th5e cap but not so good from the cap to the plugs. $25 later, I re-replaced the cap and rotor and she started up like it was brand new!!!!!!!!!! I drove it about 5 miles and it didn't spit, sputter, hiccup, pop, crack, jump, or anything!!!

In conclusion, new parts can be bad... but my truck is finally running!!!!!!!!!!!

Thanks for posting your results. Glad it worked out for you.