1997 Yukon misfire

[tim573]

Just bought a 97 yukon with the 5.7. Motor has about 20k on it and just developed a misfire. It ran fine until a couple weeks ago. Wouldnt start one day so after about an hour i went to try again and it started right up with no problems. To this day it hasnt had a problem starting up. Im a little ocd so i had to have the ses light off asap. I was getting the o2 codes and a misfire on cylinder 4 code. Because it has no cats I did the non fowlers on the o2's and cleared those codes. I put new plugs, wires, and a cps on it but, it is still misfiring. It dont start misfiring until the motor is warmed up. Not sure if it has anything to do with it but, all the lights flicker inside and out on idle and while driving.

 

[tim573]

fixed

 

[Roadboy]

What was the fix? Ground issue?

 

[tim573]

it actually just went away without doing anything but, the misfire is back!!!

---------- Post added at 01:13 AM ---------- Previous post was at 01:10 AM ----------

the lights on the other hand was the alternator. it tested good but i was planning on a big audio upgrade so i put a 300a on it and no more flickering.

 

[SunlitComet]

info on this new alt please?

Also What exactly does "all lights flickers " mean?

 

[tim573]

bought an upgraded alt off of ebay... every light flickered as in while the truck was running, every single light flickered inside and out. kind of fluctuated with the rpms

 

[SunlitComet]

so misfire not electrical light related. good. what are you doing about the misfire?

 

[tim573]

i have a new distributer to put on it and gonna try a couple things to try and fix o2 sensor problem

 

[Roadboy]

I adjusted my distributor and got mine to run right again. Still need to get it to a scanner so I can read the cam retard and set it the right way but it runs "well" for now. Hope that helps you