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Discussion Starter #1
OK my SES light stays on all the time, periodically check it and its always an O2 sensor so I dont pay it much mind. The other day driving down the interstate it starts flashing when I get above 73 ish and goes back to solid when i drop below that. Pulled codes and its still an O2 but random multiple misfires as well. Changed plugs, wires, cap and rotor not too long ago so I don't think thats the problem. Fuel pressure stays around 55-58 when driving, about 61-62 when idling. Also when I start it in the AM it fires right up but anytime after that it usually takes several seconds to start, like a couple seconds per key turn and it make take 2 or 3 key turns to start.
5.7 252K miles any ideas? maybe time to change spider?
 

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First off, is your code for the upstream or downstream O2 sensor? If you haven't addressed an upstream O2 sensor fault, replacing plugs, wires, cap, rotor, and spider aren't going to get you anywhere.
 

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Discussion Starter #4
Ok so the codes are P0137 low voltage B1 Sensor 2
p0300 random multiple misfires
P0440 evap system
 

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Ok that's downstream so it shouldn't affect your driveability. Random misfire is a common problem with the original spider, but I can't say for sure over the internet that is your exact issue. It will take some more diagnosing with a scanner to narrow it down. Maybe try some fuel injector cleaner first to see if it improves. If you need to replace it, I'd highly recommend upgrading to the MPFI version and ditch the central sequential.

Your 0440 code may be as simple as a loose gas cap or bad o-ring. Could also be the tank sending unit o-ring - those go bad as well.
 

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Your p0300 code can also happen when your cam sensor and your crank sensor aren't synchronized. I would say timing, but the distributor doesn't actually control the timing. It is very common when someone pulls the distributor usually for intake gaskets. But my concern here would be that the distributor gear wears out and will start to have a lot of play which will also throw out your alignment.

A decent scanner can show you the Cam offset (there are many things that people call it but the are all the same) Supposedly there is a way to use Torque Pro and a cheap ELM327 scanner, but I have never verified this.
 

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Discussion Starter #7
Ok that's downstream so it shouldn't affect your driveability. Random misfire is a common problem with the original spider, but I can't say for sure over the internet that is your exact issue. It will take some more diagnosing with a scanner to narrow it down. Maybe try some fuel injector cleaner first to see if it improves. If you need to replace it, I'd highly recommend upgrading to the MPFI version and ditch the central sequential.

Your 0440 code may be as simple as a loose gas cap or bad o-ring. Could also be the tank sending unit o-ring - those go bad as well.
Yea I was figuring that on the 0440, I did actually leave my gas cap loose to see if it would help with the later in the day starting issues. Thought it might be building pressure and maybe the purge solenoid was going bad. What type of diagnosing? I have a blue driver scanner, doesn't do a whole lot but does have some live data readings to look at.
 

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Discussion Starter #8
Your p0300 code can also happen when your cam sensor and your crank sensor aren't synchronized. I would say timing, but the distributor doesn't actually control the timing. It is very common when someone pulls the distributor usually for intake gaskets. But my concern here would be that the distributor gear wears out and will start to have a lot of play which will also throw out your alignment.

A decent scanner can show you the Cam offset (there are many things that people call it but the are all the same) Supposedly there is a way to use Torque Pro and a cheap ELM327 scanner, but I have never verified this.
Thought about the timing being a little off considering the miles and I dont think the timing chain has ever been replaced. I do have a new distributor just havent put it in yet. Was waiting to see if I needed to replace/upgrade the spider and do all of it at one time. I have a Blue Driver scanner but not sure if it will give me the cam offset, I know it will give me the timing advance/firing for TDC
 

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I haven't been able to find cam offset on my Bluedriver.

And yes, absolutely a worn timing change will do the same thing as a bad distributor gear. When I needed to replace the poppet injectors on my truck I was broke, but bought the MPFI upgrade set on Rockauto and just bought the cheapest one. It worked fine for me for a couple years and then I sold the truck to a friend he hasn't had any issues.
 

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one of your new spark plug wires could've come loose and rubbed through on something. Just because it was done recently doesn't mean it's good. I had that happen with #5 and my rag joint.
 
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