Haven't been here in a minute was focussing on my Cadillac project, got it mostly to a good stopping point and totalled it this past saturday. That caused me to start driving my truck again...which had developed a miss, great.

So I determined the cylinder that was missing and that it was getting adiquate fuel by the smell my truck was emmitting, upon these realizations I pulled the #1 plug and and grounded and gave the truck a start. Results; it threw plenty of fire to run the motor I thought it would need, this was confirmed when I reinstalled the plug and started it for a test drive. After a couple minutes it started missing again, now I hadn't seen any crack on the plug so I was at a loss and on a wimb decided to buy a new plug for that cylinder since to test my theory and spend as little as I could on it. That worked a little better but once again after it warmed up the miss came back and actually got much worse.

Now at this time I have installed the remaining 7 brand new plugs (factory spec and whatever gap they were shipped with since I didn't have my gapper and figured it wouldn't matter too much on a low performance engine such as this, maybe it does) it also has new rotor button and plug wires to include coil wire, but no new Cap since they gave me broken one and the one I had didn't look that bad, truth be told none of what I replaced looked that bad but I don't know what those parts should look like since the first ones I replaced had one 200K miles on them.

What I have now is a fairly smooth engine again except at moderate load and certain (I think, since it's only been a day) RPMs and at WOT, under those conditions I get a little bit of vibration that I was hoping were out of balance tires but it goes away with throttle.

When I retimed it I brought #1 to compressions stroke but maybe not fully TDC I figured close would be good enough for my means and I did get the truck running ok but I felt like it may be off and nothing has been adjusted.

Does anybdy have any idea what may be going on in my motor? Have any of Y'all heard of $50 timing sets failing in these trucks? I'm at a loss for ideas and ine 280K it's only ever ran rough from a miss....

Thank you and sorry for the book I jsut wanted to make sure you guys had all the info you would need to help

 

i had a similar problem once, and it was the injector sticking open and dumpin to much fuel to that cylinder and actually caused a "pop" sound under load. what i did to find it was to just unplug that injector and run the truck on the other 7 and drive it and the pop went away, plugged it n and it came back. so i took all the injectors off and cleaned them and got it to stop sticking and its been fine ever since.

You didnt turn your distributor did you? that controls the fuel injector timing and needs to be set with a computer technically. but you can start it and go clockwise till it stumbles and mark that spot, then go counter clockwise till it stumbles and mark that spot, then just fine the middle of the two spots. THIS IS NOT THE CORRECT WAY BUT IT MIGHT GET YOU CLOSE.

Just my 2 cents.

 

Did not turn the distributor haven't felt any need to do that. How did you clean your injectors? This sounds pretty viable because the "rich" smell was more like straight gasoline now that I think about it

 

Is there a CEL on? Gappers cost like a dollar at any auto parts store, why would you not use one? My local shop would have let me borrow one and gapped the plugs at the counter.

 

take the injectors off, you should get new o-rings and little vasoline or other lube to help with install so the rings dont get ripped. as far as cleaning what i did was a ran a wire from the pos. and neg. on battery and used these to pulse the injectors. but you need something to shoot through it right? well just so happens the can of cleaner i had if you took the nossle off it left the little stem sticking out, if you press the injector down on it it will seal up enough that the fluid will shoot through the injector when you pulse it. but like i said i woul just unplug the injector for whatever cylider you said you think the prob is on and drive it with it unplugged and see what happens.