Working on a 2000 Sonoma 4.3L! Came in with a miss and low power, checked compression and it needed a passenger head gasket so i had the heads surfaced and got both gaskets along with new plugs, wires, manifold gasket kit. got it all back together and it was still missing so i checked all the plugs and #2 wasnt getting fuel so i called the guy and he said yea he forgot to mention that they told him #2 wasnt fueling. bought a new injector and it helped some, but still a miss at idle. now heres the kicker.... i pulled the #2 plug wire and it idled better!!??!!.. lol thats right idled better not firing. so my next move was to check the distributer cap and it was a little dirty so i cleaned it up and put the wire back on and ahh a miss still. checked MAF, MAP, EGR, IAC.. this thing is getting on my last nerve at this point!! Any help would be great!


On a good note though i did recieve some of my parts today for the dyno this weekend! 13111 sensors, and a piece of roof molding that decided to take flight one day

 

We had a V6 come in with an idle issue. The wiring to the cap was off (they thought it went 135, when in reality it is 153 i believe)...well what happened was they switched 3 and 5 and didn't notice...so i would say KISS keep it simple stupid, check all the basics.

Dustin

 

checked that on both sides and its driverside - 315 / pass. - 246 then coil. unless the numbers on the cap are wrong

 

plug wire grounding....I had this happen before where the wire off ran better than when grounding out. Just a thought?

 

are the injectors in the correct location under the intake?

 

so new plug wires again.. well the guy that ownes it put three on and didnt do the other three i had to do them so he might have screwed the ones he put on
yes sir checked and double checked

 

poppet valve could be sticking, did you put a whole new spider in it?

 

Check the valve springs and pushrods?

 

well its telling me a misfire on #2 and sometimes a random misfire. im going to change the distributer cap and go from there!!!

454- no i just changed the injector that was bad but the rest of them looked good

 

could it be a bad injector? maybe switch injector spots and see if the problem follows