Car starts then stalls, have to keep foot on gas
I have a 97 Pontiac Grand Prix gtp. My car starts
then stalls, I have to keep my foot on the gas to
drive around and if not it dies. Codes came up for
mass air flow sensor, and throttle body position
sensor, replaced them and car still does the same,
then I checked the map sensor and noticed the
plug was destroyed, I fixed the plug and replaced it
with a new one, codes came up for a pcv valve, so I
replaced that with a new one and car is STILL doing
the same thing, also my mechanic said my super
charger is on its way out, now that's the 1st one I
had to buy for him to put in, he said he put marval
mystery oil in it and now says the ball bearings r kn
it's way out, can I just buy the ball bearing kit off
eBay and replace them?
Did you clean and reset the air rate after you put in the new parts? You should also reset the ECM so it can relearn the base settings. As far as the super charger, don't just patch it by replacing the nose bearings, get the entire overhaul kit and do it right, if the rest of the super charger is good.
How would I reset the air rate?
Remove the IAC unit and clean those passages and make sure the IAC still moves and is not stuck, then reinstall the IAC start engine and bring to operational temp, shut it off disconnect the IAC connector, start engine and let it try to idle in park, it should be about 500 rpm, if not then remove the little brass plug, see pic, and slowly turn the screw until you reach 500, shut off engine reconnect the connector clear the code that was set by disconnecting the IAC, Set the park brake and block the wheels, put you foot on the brake, start engine and put in drive and turn on all electrical systems fan headlights radio etc, let idle stabilize for about 1 minute, shut it all down. That's it. This is assuming that you don't have any vacuum or unmetered air leaks. HTH
As far as your supercharger goes it is highly unlikely that it is on its way out or anywhere else for that matter, particularly if it has already been replaced once. They rarely fail because there is really nothing going on in there other than a couple of bearings spinning around in synthetic oil in a sealed system. Lots of superchargers get replaced because the coupler goes and makes noise and those not in the know decide its the supercharger at fault. While they're at it they replace the coupler as well so the noise goes away and they think they've done the right thing. Of course lubricating it with something other than the factory recommended synthetic oil could cause a failure if the replacement oil is inferior to the factory lubricant. If you read your owners manual you will discover there is no maintenance schedule for the supercharger other than checking the oil level. It is basically a maintenance free device which is one of the reasons superchargers are so awesome.
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