hey guys,

ive run across a problem that i cant seem to find any info on. a little while after i installed my Vortech supercharger i got a code for the EGR. my father-in-law who is a GM "master tech" checked it out and said the egr is working and the PCM is sending the signal and all seems to be fine.

he told me that the problem is probably being cause because the PCM checks the EGR by the manifold pressure. since the supercharger has changed the pressure the stock map sensor may not read the pressures correctly thus causing the PCM to think that the EGR isnt working. he also said that the factory supercharged vehicles (such as the SC Grand Prix) use different MAP sensors.
he also mentioned programming the PCM to use the O2 sensors instead of the map to solve the problem??

will a 2 bar map sensor fix the problem? will i have to also have the PCM reprogrammed again?

OR! can i fix the problem and still pass the smog check by simply disabling the code for the EGR? but i dont want to do that because then how will i know when the egr really is bad!?!?!?

help is greatly appreciated here!!!!! living in california definately has its downfalls!

thanks,
jeremy

 

NO... that is not the problem.. seems to me you have a bad EGR solenoid

suggestion.. eliminate it.

 

eliminate the egr completely? i cant do that. ive got to pass smog.

also, he checked the valve for vacuum, okay, and he checked the solenoid which was working. this is why im having such a hard time figuring out the problem.

when is the 2bar map sensor needed?

thanks.
jeremy

 

a 2 bar map sensor will give you more problems in tuning for smogs.. you can make the car pass smog w/o egr as the lt4 has no egr

 

also the supercharger must not make any difference in your vac temps on idle... it means you may have a problem with the bypass valve.

 

so should i just have the EGR code deleted from the PCM so that i simply dont get the code anymore?

hey would you do me a favor and check out the thread below.

http://web.camaross.com/forums/showt...58#post2805458

thanks,
jeremy

 

Do you have any OEM spoilers for your SS? rear?

 

extra SS spoiler? nope sorry.

i saw a 97 SS (that was almost totally stripped of course) at a junk yard once while doing an extrication drill (im a firefighter) and i was going to cut it off with the Hurst Tool ("jaws of life") and ask how much they wanted for it hoping he would say "no charge" but i thought that would be a little unprofessional.

coulda made some $$$$ off it.......hind sight is 20/20.

did you get a chance to read that other thread?

 

In most states you are allowed two not-ready states before you fail, so if you get the EGR disabled, you should pass. I would double check that with your local station first though.

 

well im starting to think that just disabling the code is going to be the best route for me to go with this problem.

ill have my brother in law pre-test it for emissions, and if its clean i could have you disable the code right?

also Ion, do you remeber what adjustments you made to my PCM when i sent you the Dyno graph after i got the supercharger?

i was just wondering if you saved the info on the changes to each PCM you tune just incase i wanted to go back to NA but keep it programmed for the hotcam.