91whitecoonbat

i have a 91 302, when i bought it it was missing, it was cheap. i though tune up. so i replaced everything, cap rotor, plugs, wires, even distributor. also IAC and numerous relays, ive switched out almost everything twice, i also pulled the valve cover and all the valve train is moving. i can unplug the wires on cylinder 4, 6, 7 and they dont change the idle, at all. i put plug in it a ton of times, it keeps fouling them, even with nonfoulers, and it does terrible in gas, seem to run rich. doesnt seem to burn any oil as far as i can tell. its a nightmare, please help its my dd.

MONSTERPRE

cap rotor?...or did you replace both the Distributor Cap and Rotor, as they are two separate parts. Did you FOR SURE reconnect the plug wires in the correct firing order? I like to put cylinder numbers on the cap, wires, and boots.

have you replaced the coil? It sounds to me like the coil cant keep up with the demands of the RPM's, even at idle.

MONSTERPRE

oh, and run a digital timing light on your #1 plug wire, make your mark on your balancer, and be sure that the distributor isn't 180 degrees out.

bobkyle2

you should run a compression check on those cylinders.... What does the plugs look like when there fouled out......... could be an injector problem..

Nitehawkjr

I would also check the firing order to see if the motor is a regular 302 not a HO because they have different firing orders.

CRAZY

Same thing was happening to me. Truck was running really bad for the longest, checked the firing order on it and turns out the were on wrong. Placed the wires on right and, presto, the truck runs like a champ. That would be the first thing for me to tell you to do.

cmsmech1976

You need to run a compression check on those cylinders that are not changing the idle. If compression is good. Check the fuel injectors. If you dont have a automotive style stethascope you can use a long screwdriver put the tip of the screwdriver on each fuel injector with your ear on the other end of the screw driver you should hear a ticking on each injector. It is harder sometimes to use a screwdriver. easiest way is to get an automotive style stethascope at oreillys for $5 to $10.

91whitecoonbat

everything to do with the distributor has been replaced, it missed when we got it. we replaced everything, the timing has been set twice to make sure by two diff mechanics. its in time. the plugs look dark black and gunky. im kinda leanin toward fuel, anythought?

bobkyle2

check compression..

91whitecoonbat

luckily i found the 3 new injectors i bought a while back and put 6,7 in tonight cause they were easy to get to. it seem to run better, but i can still unhook the plug wire and it changes nothing, so it almost has to be rings or valves, most likely valves. cause there isnt any smoke burn. i found a 91 302 police interceptor engine with complete wiring harness and computer and all relays, it even still has the tranny, automatic though. i wonder what all i would have to change to put it in. prolly not much if i swapped the upper and lower intake over and put my accesories on. that way there wouldnt be a wiring issue. but i would like to use the police computer. what yalls thought.?
thanks again everyone for all the input