In December I started having hard starting issues and cylinder missing on my Blazer, its a 2004 LS. I've replaced the cap and rotor, plugs and wires, coil and the crank position sensor. The hard starting issue is solved but I'm still having the P0300 code pop up. I'm only getting 10.5 mpg
What is usually the problem when all of the above haven't fixed the issue?

 

IM having the same problems, have you looked at your fuel pressure? check your fuel pump, fuel filter, fuel injector, Mass Air Flow Sensor, Actual Distributor (My Teeth were shot and had to get that replaced).

 

I will check those things and post back, thanks!

 

Msg for Orig poster,, have you disconnected the neg batt term for at least 10 to 15 minutes? If you believe you fixed the actual problem and its no longer there clear the code from the computer..how long ago did you replace those items?? If ya need PM me about the problem.

 

I have disconnected the battery, and erased codes from computer. The SES light stays off for a short bit and comes back. I repalced all those parts in febuary, and I even repalced throttle position sensor and still no cure.

 

Ok sorry its been awhile but I did find the problem!!! I pulled all my plugs to find they were all firing. I had replaced the plugs and wires again and bought a new cap and rotor again, I also replaced the pick up module. After replacing those items I no longer have the miss or the P0300 code.

 

what exactly is a pick up module and where may this beast be found?

 

In the distributor
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