OBDI code 42 but no CEL?

[ERIC95TAHOE]

So i recently cleaned my egr then my service engine soon light came on. so i checked it, it was a code 32 for the egr valve. also it came up with a code 42 for the electronic spark timing. fixed the egr valve and cleared the codes. started it drove it around (no light on) checked it again clear, no codes. so out of curiosity i pulled the wire to disable the EST checked what code that puts out. sure enough its a 42. re connected it and started it again then checked it.(no light on) clear no codes... drove it for a bit came home. (no light on) checked it anyways and again it came up with 42... why would this be coming up with no check engine light? any ideas anyone?

 

[Sickblutahoe]

Obd1 vehicles pcms are a lot slower I think your PCM sees a problem but not enough of one to turn on your CEL light. Does your scanner have a scope?

 

[ERIC95TAHOE]

Obd1 vehicles pcms are a lot slower I think your PCM sees a problem but not enough of one to turn on your CEL light. Does your scanner have a scope?

no scanner, just the little key looking thing to blink the codes. i was wondering maybe it was just storing it from when i disconnected to est, before the light came on for the egr, i had the est disconnected checking my timing a while back and never reset it.

anyways i reset it again and i got nothing right now. so im going to go for a while without disconnecting the est and see what happens. if it comes up again without the light then i will be wondering

 

[SunlitComet]

It is probably an intermittent failure.

 

[ERIC95TAHOE]

It is probably an intermittent failure.

if that being so what do you think would be failing i did some googleing and it was saying ignition control module. when that fails usually it will die when it gets warm and wont start till its cooled off correct??