Help please *running and starting* issues
 

I just bought a V6 1991 Toyota 4Runner with 149,000 miles and thought I got a sweet deal on it. I drove it home 70 miles no problems at all. Pulled into the driveway, shut it off and left it about 10 minutes. Came back, turned it on and it sounded and drove like it was only running on about 3-5 cylinders, and sometimes stalling out on idle. I thought that it just might be bad plugs so I replaced the plugs with NGK Iridium's and cleaned the air filter. After replacing the plugs, it started up great and drove really strong for about 5 miles to my friends house. I left it again for about 20 minutes or so and tried starting it again...it started and then I backed up and it stalled (my fault, adjusting to a new clutch). When I tried to restart it I it would turn over with no success except for little half start that wouldn't keep it running. I tried about 10 times with no luck. I let it sit about 5 hours and came back and tried again with no success the first time. Then I tried again and it started with no issues and I made it all the way back home. Could this be related to something as simple as a bad cap and rotor? Please help if anyone knows anything. The timing belt and water pump were replaced about 8,000 miles ago. Any suggestions would be great!

So another update....I replaced the plug wires, cap, rotor, and fuel filter and am receiving the same results. I also noticed that someone replaced the air intake system with the K&N filter charger system from i think it is the 94 or 95 model, and it is just hanging in there loose. When I started it up thought today I noticed something else, it kind of sounds like it's backfiring a little bit when I get on it hard...just no power whatsoever. Please Please help me! I have a coil coming tommorow, and I might just end up taking it to a mechanic unless I can figure something out on here.

bump for help

Update....I took it to the mechanic, the mechanic looked at it and couldn't get it to do what it was doing before (didn't charge me...good mechanic). I drove it to walmart to get a key copied was in the store about 15-20 min, came out tried to start it, but it would not start. Maybe a half start to about 2-300rpm, but I couldn't keep it running (almost like no fuel from the fuel pump). So I had it towed this time back to the mechanic. Of course when it got there the mechanic got in it and it fired right up. Anyone think this sounds like fuel pump? Any help??? Any suggestions?