90 L98 crank case vent hose
03-03-2013, 06:59 AM
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90 L98 crank case vent hose
My car idles a bit fast so I pulled the throtle body to clean it. I had to unhook this hose to get the TB off. It's OK, but now would be the time to swap it out. I pulled up Advance Auto and couldn't find it. I thought this would be a common part. Where should I look?
03-03-2013, 08:03 AM
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Melting Slicks
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Normally PCV hose is packaged in a bulk length such as 3" in the auto box stores. NAPA should stock rolls & will cut what you need however it is sold by the foot. You need to know the required inside diameter.
You have been having idle issues suggest this set up from another post. The 90 TPS is non adjustable however the IAC reset & base idle setting will wotk.
NOTE: If the base idle has not been set previously there will be a small plug covering the adjustment screw hole that needs to be removed.
Connect a paper clip, to your diagnostic terminal under your dash connect to terminal A and B (the top right two pins).
Turn on ignition but don't run the engine.
wait at least 30 seconds and then remove the idle air valve connector (IAC) (the square plug) then turn of ignition and unplug the paperclip.
Now remove the timing connector a single wire near the fuel pump relay.
Start your vette and set the idle speed to 400 rpm in neutral (auto trans) 450 rpm (manual trans) then check your throttle position sensor,
the top two wires it should be set to 0.54volts dc, also confirm with engine off that the tps rises to 4.5 volts at full throttle.
Turn of the ignition and reconnect the iac valve connector and timing connecter and start your vette.
it should go to 1200 rpm then drop slowly to 600 rpm, take the car for a 15 minute drive with the usual stop lights.
It is normal for a little hunting while the ecm relearns, also do a few spirited take offs.
All should settle after 15 to 30 mins normal driving and have a stable idle.
You have been having idle issues suggest this set up from another post. The 90 TPS is non adjustable however the IAC reset & base idle setting will wotk.
NOTE: If the base idle has not been set previously there will be a small plug covering the adjustment screw hole that needs to be removed.
Connect a paper clip, to your diagnostic terminal under your dash connect to terminal A and B (the top right two pins).
Turn on ignition but don't run the engine.
wait at least 30 seconds and then remove the idle air valve connector (IAC) (the square plug) then turn of ignition and unplug the paperclip.
Now remove the timing connector a single wire near the fuel pump relay.
Start your vette and set the idle speed to 400 rpm in neutral (auto trans) 450 rpm (manual trans) then check your throttle position sensor,
the top two wires it should be set to 0.54volts dc, also confirm with engine off that the tps rises to 4.5 volts at full throttle.
Turn of the ignition and reconnect the iac valve connector and timing connecter and start your vette.
it should go to 1200 rpm then drop slowly to 600 rpm, take the car for a 15 minute drive with the usual stop lights.
It is normal for a little hunting while the ecm relearns, also do a few spirited take offs.
All should settle after 15 to 30 mins normal driving and have a stable idle.
Last edited by Churchkey; 03-03-2013 at 08:14 AM.
03-03-2013, 10:24 AM
#3
Le Mans Master
03-04-2013, 10:59 PM
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Normally PCV hose is packaged in a bulk length such as 3" in the auto box stores. NAPA should stock rolls & will cut what you need however it is sold by the foot. You need to know the required inside diameter.
You have been having idle issues suggest this set up from another post. The 90 TPS is non adjustable however the IAC reset & base idle setting will wotk.
NOTE: If the base idle has not been set previously there will be a small plug covering the adjustment screw hole that needs to be removed.
Connect a paper clip, to your diagnostic terminal under your dash connect to terminal A and B (the top right two pins).
Turn on ignition but don't run the engine.
wait at least 30 seconds and then remove the idle air valve connector (IAC) (the square plug) then turn of ignition and unplug the paperclip.
Now remove the timing connector a single wire near the fuel pump relay.
Start your vette and set the idle speed to 400 rpm in neutral (auto trans) 450 rpm (manual trans) then check your throttle position sensor,
the top two wires it should be set to 0.54volts dc, also confirm with engine off that the tps rises to 4.5 volts at full throttle.
Turn of the ignition and reconnect the iac valve connector and timing connecter and start your vette.
it should go to 1200 rpm then drop slowly to 600 rpm, take the car for a 15 minute drive with the usual stop lights.
It is normal for a little hunting while the ecm relearns, also do a few spirited take offs.
All should settle after 15 to 30 mins normal driving and have a stable idle.
You have been having idle issues suggest this set up from another post. The 90 TPS is non adjustable however the IAC reset & base idle setting will wotk.
NOTE: If the base idle has not been set previously there will be a small plug covering the adjustment screw hole that needs to be removed.
Connect a paper clip, to your diagnostic terminal under your dash connect to terminal A and B (the top right two pins).
Turn on ignition but don't run the engine.
wait at least 30 seconds and then remove the idle air valve connector (IAC) (the square plug) then turn of ignition and unplug the paperclip.
Now remove the timing connector a single wire near the fuel pump relay.
Start your vette and set the idle speed to 400 rpm in neutral (auto trans) 450 rpm (manual trans) then check your throttle position sensor,
the top two wires it should be set to 0.54volts dc, also confirm with engine off that the tps rises to 4.5 volts at full throttle.
Turn of the ignition and reconnect the iac valve connector and timing connecter and start your vette.
it should go to 1200 rpm then drop slowly to 600 rpm, take the car for a 15 minute drive with the usual stop lights.
It is normal for a little hunting while the ecm relearns, also do a few spirited take offs.
All should settle after 15 to 30 mins normal driving and have a stable idle.
03-04-2013, 11:00 PM
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03-05-2013, 07:55 AM
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Melting Slicks
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The plug is still there. I couldn't get it out easily and didn't want to get too rough though. What's it take to get it out? I have the shop manual, it mentions the IAC procedure. I figured it was best to replace the hoses first to make sure I had no vac. leaks. I want to check for diognostic codes too but again, I want the best case senario to start with.