My 4.3 has a miss
 

My truck had been sitting for a month or so while I was working on it. Id start it & move it around but didnt drive it much. After I got it going I noticed it had a slight miss that would seem to go away after it warmed up. The other night after I had all the painting done I wanted to go cruise around but the miss wouldnt go away. I went & put some gas in it & drove it out a few miles & back but it was still there. Its been forever that its been tuned so I put in a new set of plugs & wires but still missing. Any Ideas? Almost sounds like vacuum but Im not sure. Tomorrow Ill run the code scanner to see if its throwing any codes. It ran perfect before I changed the headlites to composite & painted the truck. The only other thing I changed was the bed (new filler hose too). Hope I dont have an intake leak! I really want to drive this beast!

Re: My 4.3 has a miss
 

I just ran my scanner...
PO135 (bank 1 02 sensor?)
PO300 (injector)

I did notice the 1,3 & 5 plugs were black sootier than the 2,4 & 6 were. Any ideas? Please dont say injector. :lol:

Re: My 4.3 has a miss
 

Check out this link. It will give you some insight to how to fix this.

http://www.s10forum.com/forum/f107/s...de-kit-324166/



I would change the O2 sensor first...it is a little cheaper.

Re: My 4.3 has a miss
 

I would check for a weak coil or the wires that connect to it.

Re: My 4.3 has a miss
 

I ran some good injector cleaner through it & no change. I changed the bank 1 sensor & it seemed to help a little. The old plugs that I took out were clean on the passenger side but black on the drivers side. All fuses are good & I cant find any vacuum leaks. I guess the injector is next maybe. Im going to try a new fuel filter tomorrow but Im not holding my breath. Im not happy when my truck is not happy...

edit: I forgot, its throwing 5 codes after the sensor change
132
134
135
137
304

Re: My 4.3 has a miss
 

Do you know what the codes are? If you don't, I could post them for you.

Re: My 4.3 has a miss
 

why can't I hear about this stuff when I'm at work? you have my # Larry (guilt trip)

IIRC the P013X's are O2 related. P0135 is O2 1-1 not switching, I think.

at first you said you have sooty plugs on bank 1 but later you show a code P0304 (cyl 4 miss). I would be curious to see what the missfire counters are. sometimes a cylinder after the one missing can show as a miss, ie. #5 is missing but #4 is counting.

all 3 on bank 1 leads me away from an ignition miss. I would have to see the fuel trims to be sure. I am thinking you may have a leaking fuel pressure regulator.

I will talk to the warden and see if next weekend I could take a trip and bring some tools/scanner. BTW, I need to stretch the legs on my Kaw. NO, I will not have room to bring a muffler back with me. LOL

Re: My 4.3 has a miss
 

:lol: Its a pretty mild feeling miss so I was wondering if it could be the cheapie cap & rotor I put on last year. I cleaned it up a little the other night & put it back on but it didnt help. Thats when the code went from O300 to 0304 so..........I got a new cap & rotor today along with a new fuel filter. I am going to clean out the TB reeeeeeal good today & swap the above parts. I also bought a fuel pressure gauge to test my fuel pressure. Ill let you know, may call next week. E or PM me your work #. Ill call from work, cell is dead till next week (Im broke now). Sheesh, Im not happy with this thing. Oh, is there anyway at all this could have led from me changing out the fuel filler tube to the stepside style? Thats exactly when this started & I saw where a certain van tube caused problems & it gave me this idea...Tired of typing now...

Re: My 4.3 has a miss
 

it's a good thing you didn't say it was "missing". I would have to be a smarta$$ and tell you to look under the hood.

BUMP and looking for you to say you checked the regulator.

Re: My 4.3 has a miss
 

Yep, I checked. Its still under there with all the other crap!

My phone works again...:)

Re: My 4.3 has a miss
 

have you figured out this problem yet? cuz im having the same one with my 97 blaze and im bout ready to shoot it....

Re: My 4.3 has a miss
 

Pretty sure its the injector but it will be parked it for the year pretty soon, so I dont want to change it & let it sit for months with it gumming up . Ill change it out this winter sometime.

Re: My 4.3 has a miss
 

ok,cuz mine was throwing #4 so i changed it last week but i drove it today and still did it. as i read your thread i saw something about #5 might realy be the problem in stead of number 4

Re: My 4.3 has a miss
 

so maybe ill just crack mine back open and try that