Thanks Captain. It set a code today P0303-- clear it and it sets it again. Checked all the plug wires- (almost New wires) they on tight and none crossed. Only plug I took out was #1. cked it again no cracks. Wandering if rotor got messed up pulling the dist in and out so much.

 

Also I think i am right that p0303 is a CYL #3 MISFIRE. could this be a injector issue. Vehicle was running smooth no Injectors issues befor the intake was replaced.

 

You're correct, P0303 is a misfire on #3 cylinder. Could be any number of things causing it: plug, plug wire, injector, injector wiring, collapsed lifter, worn camshaft, etc etc. Doubtful it's the rotor or it would affect all cylinders. Are you sure the
cap is wired correctly? Notice #1 & #3:



Post the freeze frame data for when the DTC set in memory, that should help. Really need to check fuel trim to see if it's a lean misfire or a rich misfire, a screen shot would be very helpful. That will narrow down the possibilities a ton. Need to see LTFT and STFT for both banks, engine at operating temp, at idle and 2K rpm. Post the results.

 

bad news is that i dont have a live scan device. I am thinking it is an injector issue because i swaped the plugs and wires -- and still have same issue. is there a way to test the injector -- do i have to take the spyder apart. welcome comments

 

Good job! You're using the PCM to help you diagnose! If the P0303 stayed the same after the swap, it could be an injector issue. If the plug was wet, the injector could be stuck open or not sealing when closed. If the plug was dry, the injector might not be opening. Could also be a problem with the electrical circuit for the injector. You can check injector balance, but it requires a bi-directional scan tool, (big money). Could also be a problem with compression, a valve issue, or a vacuum leak that only affects cylinder #3. This is where fuel trims are a huge help.

 

Well snow and ice is gone today. Started back on trouble issues. Cleared codes and it reset the 303. new plugs. reset and i got 305 then 304 cleared it then.---- 300 now. rechecked the connector to the spyder it was fine. One thing i did notice was the vaccum supply was low off canister but functional. It does take a few minutes 4-8 for the 300 to set but you can fell the miss. Yes rechecked wires and firing order one by one installed. almost ready to scrap it, but is is a 2000 with only 113k- Thinking now to try and replace cap and wires

 

could the sensor in the distributor be the problem - I HAD TO change the dist base when i did the intake because it had a broken ear where the cap srew goes.

 

Unless you have the kind of luck that it takes to win the lottery, your cam retard (CMP) is off. Happens any time the distributor hold down bolt is disturbed. Takes a capable scan tool and user to set it. If the gap is too large, the spark can jump to the wrong terminal. I would advise taking it in to a capable shop (unless you have a buddy) to set the CMP retard.

(By the way I learned this from the Hook School of Blazers....Inc. )

 

^^ Yup. Use AC Delco only for cap & rotor. The camshaft position sensor, (inside the distributor) will NOT cause a no start condition.

 

it runs just rough beause of misfires/ So yu think THE cap and rotor could be the cause of my p0300 code and 303, 304 305 ---it random as i clear the codes and run it again