I am at a stump here. I thought I had bad gas in my 94 hardbody, 4 cyl, approx 200K miles. it is idling very rough. I changed the fuel filter and the fuel line to the filter, but didn't get any better. I added a bottle of HEAT and it ran better for about a day. I had this problem once when the injectors were clogged, so I sprayed car cleaner into the throttle body, but didn't do any good this time. I pulled a couple plugs and they look normal. there was some carbon buildup on the contacts inside the distributor cap so I replaced that and the rotor, but still no difference. I thought the cat converter was clogged, but after removal of that, it still didn't do any good. it runs just fine when I rev the motor and on the highway, but it's rough holding rpms below say, 2000. I sure hope it's not a cam problem, I don't have the money to dump into it right now!