P0301
#1
03-02-2011, 06:47 PM
P0301
Yesterday I replaced cap/rotor/wires and plugs including the secondary air pump. Now ever since I did both of those tasks, I am getting a cylinder #1 misfire. I only had one code prior to that and it was the airpump.
It idles fine in neutral, but in forward or reverse the rpms fluctuate between (according to my laptop)590 and 690rpm. It seems just a tad sluggish when taking off, but as the RPM's increase past(2500+) it seems to run fine.
BTW, removing the #3 plug was easier to do than replacing the wireset.
It idles fine in neutral, but in forward or reverse the rpms fluctuate between (according to my laptop)590 and 690rpm. It seems just a tad sluggish when taking off, but as the RPM's increase past(2500+) it seems to run fine.
BTW, removing the #3 plug was easier to do than replacing the wireset.
#3
03-04-2011, 12:57 AM
Yep, checked and double checked.
If it was vacuum leak related, would it throw a random misfire?
I took the truck to work tonight 13 miles one way, and had my laptop running the whole trip. Not one single instance of a misfire. On the way home, same thing, no misfire. The engine continues to idle erratically and miss up through the RPM range.
Reminder, none of this happened prior to the tune up and smog pump replacement.
If it was vacuum leak related, would it throw a random misfire?
I took the truck to work tonight 13 miles one way, and had my laptop running the whole trip. Not one single instance of a misfire. On the way home, same thing, no misfire. The engine continues to idle erratically and miss up through the RPM range.
Reminder, none of this happened prior to the tune up and smog pump replacement.
#6
03-04-2011, 02:52 PM
Couple of things to check:
Fuel pressure and leakdown...key ON, engine OFF, fuel pump running... pressure must be 60psi to 66psi and must remain above 55psi for 10 minutes after the fuel pump shuts off.
These engines are very particular when it comes to secondary ignition parts. The wires and air injection reaction pump are probably ok however, I would suggest AC Delco plugs #41-993 with a gap of .060" and an AC Delco cap and rotor. Make sure you put a dab of silicone dielectric grease on each terminal, inside and out, of the cap. Ask the boys at Autozone if you can upgrade to the good/right stuff.
Fuel pressure and leakdown...key ON, engine OFF, fuel pump running... pressure must be 60psi to 66psi and must remain above 55psi for 10 minutes after the fuel pump shuts off.
These engines are very particular when it comes to secondary ignition parts. The wires and air injection reaction pump are probably ok however, I would suggest AC Delco plugs #41-993 with a gap of .060" and an AC Delco cap and rotor. Make sure you put a dab of silicone dielectric grease on each terminal, inside and out, of the cap. Ask the boys at Autozone if you can upgrade to the good/right stuff.
#7
03-04-2011, 03:10 PM
i just had the same problem about a week ago when doing a tuneup, the problem ended up that 1 of the plugs i got from the shop had a hairline crack in the ceramic/porcelin whatever u wanna call it.....check into that for sure sounds like the same issue to me let me know when u check it out
#9
03-09-2011, 12:09 AM
Found the culprit....
#1 sparkplug cracked.
Going back to Autozone and get a replacement tomorrow. I stuck one of the older ones back in and it runs MUCH better, and no longer throwing a misfire code.
#1 sparkplug cracked.
Going back to Autozone and get a replacement tomorrow. I stuck one of the older ones back in and it runs MUCH better, and no longer throwing a misfire code.