High Idle

[bldavis11]

I finally have everything back together from replacing the injectors. Of course then the alternator clunked on me, and now that's fixed. I now have a persistent high idle which I really feel is related to my aggressive TB cleaning when I had everything apart. It's not he MAP hose, and there is no vacuum leak. I'll try blocking off the TB with a stiff piece of cardboard or such later this week to confirm.

I understand that there is a little bit of grease that is supposed to seal the TB blades. If that was ever there, it's now long gone. How do I go about fixing this little problem that I've created? Is simple axle greese on a Q-tip applied around the edges of the three blades enough?

[A26B]

It's not grease, but more like a paraffin compound called "Dag" and was used on the secondary throttle bores.

Greg VanDeventer fits throttle blades exactly to the bores on his modified 63mm Throttle Body and eliminates the need for any compound to seal them.

You might try mixing up some soft candle paraffin with a compatible solvent and "paint" the bores where the blades would normally seal.

[Franke]

I finally have everything back together from replacing the injectors. Of course then the alternator clunked on me, and now that's fixed. I now have a persistent high idle which I really feel is related to my aggressive TB cleaning when I had everything apart. It's not he MAP hose, and there is no vacuum leak. I'll try blocking off the TB with a stiff piece of cardboard or such later this week to confirm.

I understand that there is a little bit of grease that is supposed to seal the TB blades. If that was ever there, it's now long gone. How do I go about fixing this little problem that I've created? Is simple axle greese on a Q-tip applied around the edges of the three blades enough?

Did you do anything to the IAC or the TPS?

[bldavis11]

Did you do anything to the IAC or the TPS?

They TPS was removed and reinstalled. I've messed with it since my high idle problem. If I rotate it CW or CCW from it's current position, the idle increases.

The IAC remained inplace, though I have removed it to clean it several years ago.

[gbmidyear66]

Marc Haibeck will also bore your TB and custom fit the blades. I had mine done when I ported the intake. I have no DAG - but no idle issues.

I'd just make sure first (before you get into a TB rebuild) that you don't have a vac leak somewhere - I think that is the more likely situ. Very easy to miss a hose connection when you replace the plenum. Also, if one if your new injectors is not sealing properly - you will have a vac leak (ask me how I know....)

[randy ransome]

I've developed a high idle also and can't figure it out. I don't know if it is a vacuum leak or something else.

Do ya'll not recommend using carb cleaner to narrow down if it's a vacuum leak? I haven't changed anything it just started idling high.

[GOLDCYLON]

I've developed a high idle also and can't figure it out. I don't know if it is a vacuum leak or something else.

Do ya'll not recommend using carb cleaner to narrow down if it's a vacuum leak? I haven't changed anything it just started idling high.

Check to make sure you didnt blow off the MAP hose on the back of the plenum

[randy ransome]

Yea I checked that. It's blown off before but I put a wire tie on it.

[GOLDCYLON]

Yea I checked that. It's blown off before but I put a wire tie on it.


When you rap the gas does the idle drop to normal ? if it does more than likely you secondary throttle plates are sticking

[bradley]

you can use a propane torch to find your vacuum leak .just get a 3/8 fuel line and attach it to the end of the torch .turn on the gas and when you find the leak the rpms will rise

[gbmidyear66]

Or, if you're afraid you might torch the garage in the process (like me) - you can use a spray bottle with water - your idle will decrease when a leak sucks in the water