I just looked up all the RPO codes for my 87 Sports Coupe, which is CCC Q-jet (LG4), and I came across this one code: E7Z - SENSOR VEH SPD - DELETE. Now doesn't the computer need this sensor to adjust fuel, air, tranny, and electronic cruise control(which is a functional option on my car, code-K34). Can any of you guys enlighten me?

Heres the website i got the code from- http://4x4.straydogs.ca/gmrpo.html

 

I believe you are running into the GM reuse of RPO codes.

https://www.thirdgen.org/forums/hist...-question.html

 

Keep in mind that you have a mechanical Speedometer (cable driven). REally the computer does not need that stuff, cars ran for almost 100 years with a carburator and there was no computer to control them. Cruise control is electronic but it is independant of the sensor that is being used there. In 1984 they went to a compuer controled system, in 1982 & 1983 they used Vacuum.

As for your ECM it does take readings from the O2 sensor to lean it out or make it more rich, the Spark knock sensor tells the ECM to retard timing, is pretty basic as for function. The Fuel Injection systems are much more complecated as they will not run without an ECM. in that case the Computer takes readings from the MAF or MAP sensors, TPS, O2, and calculates the amount of fuel, creates a pulse width etc...

John