alvaroemg
I'm Awesome
1999 chev suburban k1500 5.7 , 167,820 miles
Here i will document my journey in fixing my misfire code.
To start, I replaced the heads about 8 months ago. Both were cracked and the machine shop told me it would be cheaper to get brand new heads and they would do the valves and seals.
Once complete the head job, I had misfires on many cylinders and truck was running rough.
I re-adjusted my rocker arms with the truck running and it was running better with most misfires gone but on #2. Distributor was still out of time and for the life if me, i could not get it lined up properly so i took it to a local mexican guys shop.
He also did all 16 lifters as I had ticking on the left side. Purchased MELLING JB2079 from RockAuto.
He zero’d in the distributor and called me that the truck was ready a few days later.
a few days later(its been raining and cold weather) misfire on #2 came back, sometimes turning to multiple cylinder misfires.
When the weather is nice, misfire disappears but comes back later throughout the day. Or ill stop at the store and turn it back on and its gone.
I should of replaced my injector spider when I did the heads but i didn't due to funds. So finally i decided to deal with the #2 misfire and jumped to the main repair i’ve been thinking of for months. I purchased the FJ504 standard Injector spider and swapped it out yesterday. My intake plenum was pretty clean as I don’t have over 1000 miles on the new heads yet.
Swapped the spider out, checked for leaks by unplugging the ignition spark cable and priming the fuel. Everything checked out, finished installation. Truck started right up and was idling great. On my way home(i was at a friends shop doing the swap) CEL came back on. I already knew what it was.
I got home, plugged my little $20 scanner and sure enough, P0302 code came up. I erased it and drove for a bit last night and it didn’t come back. Response is pretty good from the throttle, something i’ve never had and it made me smile when I stepped on it.
I took some pictures of my scanner at idle with the CEL on prior to erasing it, if anyone can chime in on what they mean.
My plan is to:
1- Check/replace spark plug/s.(new about 2 years)
2- Replace wires(new about 2 years, maybe wire routing is wrong)
3- check cap and rotor (distributor is brand new from Bravex, 4 months old)(Might upgrade to the blue standard cap and rotor).
4- run fuel psi test
5- run compression test
6- run a can of seafoam injector clean on the throttle body for possible sticking intake valve
7- run a ratio of 1ga/1oz of seafoam in my fuel tank. My tank holds 42 gallons, so I will use 42oz of seafoam.
8- replace my fuel filter after the gas tank seafoam treatment(filter is a K&N filter)
9- replace all 4 o2 sensors(they are due for un upgrade)
My starting order would be #4 followed by #5.
Here i will document my journey in fixing my misfire code.
To start, I replaced the heads about 8 months ago. Both were cracked and the machine shop told me it would be cheaper to get brand new heads and they would do the valves and seals.
Once complete the head job, I had misfires on many cylinders and truck was running rough.
I re-adjusted my rocker arms with the truck running and it was running better with most misfires gone but on #2. Distributor was still out of time and for the life if me, i could not get it lined up properly so i took it to a local mexican guys shop.
He also did all 16 lifters as I had ticking on the left side. Purchased MELLING JB2079 from RockAuto.
He zero’d in the distributor and called me that the truck was ready a few days later.
a few days later(its been raining and cold weather) misfire on #2 came back, sometimes turning to multiple cylinder misfires.
When the weather is nice, misfire disappears but comes back later throughout the day. Or ill stop at the store and turn it back on and its gone.
I should of replaced my injector spider when I did the heads but i didn't due to funds. So finally i decided to deal with the #2 misfire and jumped to the main repair i’ve been thinking of for months. I purchased the FJ504 standard Injector spider and swapped it out yesterday. My intake plenum was pretty clean as I don’t have over 1000 miles on the new heads yet.
Swapped the spider out, checked for leaks by unplugging the ignition spark cable and priming the fuel. Everything checked out, finished installation. Truck started right up and was idling great. On my way home(i was at a friends shop doing the swap) CEL came back on. I already knew what it was.
I got home, plugged my little $20 scanner and sure enough, P0302 code came up. I erased it and drove for a bit last night and it didn’t come back. Response is pretty good from the throttle, something i’ve never had and it made me smile when I stepped on it.
I took some pictures of my scanner at idle with the CEL on prior to erasing it, if anyone can chime in on what they mean.
My plan is to:
1- Check/replace spark plug/s.(new about 2 years)
2- Replace wires(new about 2 years, maybe wire routing is wrong)
3- check cap and rotor (distributor is brand new from Bravex, 4 months old)(Might upgrade to the blue standard cap and rotor).
4- run fuel psi test
5- run compression test
6- run a can of seafoam injector clean on the throttle body for possible sticking intake valve
7- run a ratio of 1ga/1oz of seafoam in my fuel tank. My tank holds 42 gallons, so I will use 42oz of seafoam.
8- replace my fuel filter after the gas tank seafoam treatment(filter is a K&N filter)
9- replace all 4 o2 sensors(they are due for un upgrade)
My starting order would be #4 followed by #5.
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