Code 36 Opti-Spark Ignition Timing (Resolution Pulse) '93 Lt1??
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Joined: Aug 2003
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From: Lebanon ME
Code 36 Opti-Spark Ignition Timing (Resolution Pulse) '93 Lt1??
I have a code 36 High Resolution Spark Failure, according to my Mac Tools Scanner, on my '93 Lt1 Coupe. Just curious if anyone else has had this problem and what you did to solve it. (Opti-Spark Replacement, ECM, PROM, Plug Wires??). It runs rough and the #8 and #6 injectors are not pumping enough fuel into the cylinders on the right side. Thanks in advance.
:confused:
:confused:
Team Owner
Joined: Aug 2000
Posts: 40,156
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From: San Pedro CA
Re: Code 36 Opti-Spark Ignition Timing (Resolution Pulse) '93 Lt1?? (lt1_corvette93)
any code from the opti a bad thing... and the main cause, I THINK goes like this:
The opti's high voltage side carbon traces from water getting in... that causes misfires... the computer cannot correct...
That's my latest theory... I would love to hear from others if this makes sense!
The opti's high voltage side carbon traces from water getting in... that causes misfires... the computer cannot correct...
That's my latest theory... I would love to hear from others if this makes sense!
Melting Slicks
Joined: May 2001
Posts: 2,143
Likes: 7
From: San Diego CA
Re: Code 36 Opti-Spark Ignition Timing (Resolution Pulse) '93 Lt1?? (lt1_corvette93)
Get ready to replace the opti. I know a F-body guy that just took his old Opti apart cleaned it very well and replaced it for another 20K+ miles (and still going!), but he's lucky at cards too.
Unless you like to tinker and have the time, do it once and replace the whole thing. A low resolution fault is in the optics/electronics side.
Here's a pretty good description of an opti-spark: http://www.charm.net/~mchaney/optisprk/optisprk.htm
Unless you like to tinker and have the time, do it once and replace the whole thing. A low resolution fault is in the optics/electronics side.
Here's a pretty good description of an opti-spark: http://www.charm.net/~mchaney/optisprk/optisprk.htm
Race Director
Joined: Feb 2003
Posts: 11,672
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From: Lake Wylie SC
Re: Code 36 Opti-Spark Ignition Timing (Resolution Pulse) '93 Lt1?? (lt1_corvette93)
We all seem to agree that you are in for an Opti replacement. My advice is to go with a new OEM AC Delco Opti-spark, plug wires (MSD or Taylors), Plugs (NGKs or AC Delco Rapid fires or maybe Densons) and while you have the water pump off replace it. One thing, vent the opti-spark (see http://www.corvetteclinicinc.com C4 solutions). The other option would be to go with a Dyna-spark from Dyno- Tech (on the left column). You could also go with an electric water pump. See tools>tech tips>C4>meziere install. There is lots of info on this right here.
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Re: Code 36 Opti-Spark Ignition Timing (Resolution Pulse) '93 Lt1?? (lt1_corvette93)
One option that nobody has mentioned here actually happened to me. The opti has a short pigtail that connects it to the rest of the car's wiring harness. Pull this connector and take a look at it. Make sure that all the connections look good. If they are corroded or damaged it can cause signal troubles.
I had this happen and replaced the opti before I figured it out. In my case I replaced a perfectly good opti because the connections had somehow corroded up inside this connector. It might not be the problem but it would certainly be easy to look at.
The only problem is that this little 2-3 foot pigtail costs something like $70
It's still better than $300 for an opti though.
I had this happen and replaced the opti before I figured it out. In my case I replaced a perfectly good opti because the connections had somehow corroded up inside this connector. It might not be the problem but it would certainly be easy to look at.
The only problem is that this little 2-3 foot pigtail costs something like $70
It's still better than $300 for an opti though.
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Joined: Aug 2003
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From: Lebanon ME
Re: Code 36 Opti-Spark Ignition Timing (Nathan Plemons)
Thanks guys, for all the input. However, I got angry and parked the car for the winter. Curses to GM's opti-spark design! I'll deal with the opti replacement next spring. I'm sure I can find some aftermarket goodies, over the winter, to bolt on while I have everything apart also. Thanks Again,
Emery :chevy
Emery :chevy
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