OBD1 conversion
#1
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Ok i thought i read some where that the instructions posted by that Bbody guy with the soldering of the resistors doesnt work with the fbody because we only have one knock sensor. is this right or can i just follow those instructions? anyone have that link, i lost it.
also Ed wright(i hope you see this) mentioned theres a code that needs to eb turned off and thats it. any one know about this?
i just need to be able to unplug and replug and go. i know either of these ways will work, i just didnt know of any advantages of one over the other. thanks
also Ed wright(i hope you see this) mentioned theres a code that needs to eb turned off and thats it. any one know about this?
i just need to be able to unplug and replug and go. i know either of these ways will work, i just didnt know of any advantages of one over the other. thanks
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That would be code 43, if yer using tunercat it's under the ecm switch table. That's all I did and normal knock retard still works fine. If you don't turn that off or do the diode mod then I think it automatically will pull out something like 10 degrees, I think I read that somewhere.
#3
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how is it that code 43 will keep the SES light off, but knock retard will work all the same? especially when the knock sensors between the two ECMs is different? Ed was the first person ive heard mention this. it just sounds too easy when people are all about wiring in resistors and switching knock sensors to make this conversion work. thanks
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I think this is how it works from what I've read........There is a different resistance (ohms) for each type of knock sensor. The OBD1 ecm sees a different resistance than it's suppose to so it throws a code thinking the sensor has gone bad but actually the sensor is fine just not the resistance the ecm thinks it should be, therefore if you turn code 43 off then it wont throw that code. I went back and found the thread in which Ed Wright told me about turning the code off and it works fine. Here's that thread https://ls1tech.com/forums/lt1-lt4-modifications/238831-obd1-conversion.html
I did it and have logged lots of data since then and I still have knock retard. I put in a bunch of timing once just to make sure it was working and trust me it works!
I did it and have logged lots of data since then and I still have knock retard. I put in a bunch of timing once just to make sure it was working and trust me it works!
#5
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yep thats the thread i was referring to. so thats it? code 43 turned off and everything works as is? no resistors or knock sensor/modules to switch out? man thats great. why then does everyone go to the trouble of soldering in resistors and switching knock sensors/modules? thanks speed
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Yep that's it. I did put in an LT4 knock module. The car was sorta surging and the acceleration wasn't smooth at all after the headers and duals so I put in the LT4 module and it smoothed it right out. I really don't know why people go thru all the trouble of soldering in new resistors, unless they just don't know you can turn code 43 off and everything be fine.
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Originally Posted by Snow Dog
yep thats the thread i was referring to. so thats it? code 43 turned off and everything works as is? no resistors or knock sensor/modules to switch out? man thats great. why then does everyone go to the trouble of soldering in resistors and switching knock sensors/modules? thanks speed
Good luck, Ed
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Originally Posted by Ed Wright
Shut off error code 43, and everything will be fine. With an Impala you have to do something about the tach. I ran mine that way for two or three years, and knock retard function is completely normal. I have easily 40 or 50 customers with LT1 F body cars running around that way. I don't see a need for an LT4 knock sensor module, either. I control sensitivity with the tuning. I never waste money on those things.
Good luck, Ed
Good luck, Ed
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