I have an 02' 4.8 full bolt on truck with the radix and its five speed...my truck has been runing fine and now out of nowhere it has a dead miss to it...under easy driving it doesnt do bad but if you get on the throttle at all it starts jumping, missing, and popping..i have a fuel pressure gauge that is showing good pressure. I changed all the plugs(all looked fine) and wires..swaped O2 sensors..and put diff gas in it and still the same..?? im lost on what to do...going to put the wideband on it tommorow and see if it can tell me something...anybody have any thoughts or opinions? they are greatly appreciated!

 

changed the wires? do a compression test. who did the tuning?

 

yeah i changed the wires to...A friend of mine did the tuning...he has been tuning for about six years so i dont think that would be an issue. Im meeting with him tommorow to stick the wideband on it and see what that tells us

 

everything looked fine on the wideband...i guess the next step is to check the compression..

 

isolate which cylinder is missing first.Then try switching coil packs.I had a coil go bad with same miss you are describing.

 

It's not throwing any codes or showing any pending codes??? How about a cloged injector??? Fuel pressure is only at the line. You can't see a clog at the injector, how ever you can test for it. Put a gauge on the fuel system. Energize the fuel system. Assuming your pump is good and its not bleeding off pressure energize each injector momentarily to see if bleads of pressure. re-pressure's the system between injector test. If its cloged injector it won't bleed off at the same rate as the others.
Its Very important that you energize the injector properly!!! If you power it up in reverse you may damage the injector!!!

If you can't find any thing else first with the plugs, coil, wires, electrical, The tune or so on and you don't feel comfortable with energizeing the injectors, take it to a shop who knows what they are doing....

 

The check engine light flashed at me a few times..i pulled over and shut the truck off, started it, and it never did anything again...for once i wish it would come on so it could let me know something...i have another set of coil packs for the truck that im going to swap next to see if that will fix it....then if that does not work i will have someone check the injectors and see ab that....one question on the injector,..would the wideband picked a bad injector up?

 

were did you put your wideband?? may not have gotten that bank

 

Depending on how its set up it might tell you what side is running Lean or rich if an injector is cloged or not functioning right... When the check Engine Light flashes, Thats A Sign something Is wrong!!! Its the cars way of telling you that your enginge is not runing right and that your going to damage the catylitic converter. When the light comes on It makes a note in the Cars computer. The code should still be stored in the cars computer unless you cleared it or disconnected the battery.

 

Yeah i know what it means when the check Engine light flashes..When i put the plugs back in it after checking them i messed one up and thats why it was flashing..but it has not came on since..I have no cats on the truck.