Vacuum leak

[MuRCieLaGo]

Hi,

My '91 ZR-1 got a vacuum leak. Key on, the vacuum pump turns on every seconds or so.

-Blocked the vacuum port directly on the pump - stops running (so the pump is fine).
-PCV valve was loose so I fixed it by installing vinyl sleeves.
-I tightened a lot of hoses - most of them were loose.

I'm very afraid of pulling the plenum now. Especially because I don't want to spread antifreeze everywhere.

Can I say goodbye to my vacuum problem if I remove the secondary system? If I do so, I will order a chip from Haibeck. Will I be able to switch to normal mode or I will be locked to Full Power?

[Dynomite]

Originally Posted by MuRCieLaGo

Hi,

My '91 ZR-1 got a vacuum leak. Key on, the vacuum pump turns on every seconds or so.

-Blocked the vacuum port directly on the pump - stops running (so the pump is fine).
-PCV valve was loose so I fixed it by installing vinyl sleeves.
-I tightened a lot of hoses - most of them were loose.

I'm very afraid of pulling the plenum now. Especially because I don't want to spread antifreeze everywhere.

Can I say goodbye to my vacuum problem if I remove the secondary system? If I do so, I will order a chip from Haibeck. Will I be able to switch to normal mode or I will be locked to Full Power?

Finding A Vacuum Leak

Full power all the time with secondaries removed. I would just remove the plenum (block TB Coolant when you are there) and find/fix the vacuum leak. Just drain a gallon or so of coolant and remove the Plenum.

Removing Plenum (including the 10 minute Plenum Removal)

Injector Housing TB Coolant Blocking

You can also Block TB Coolant without removing the Injector Housings but do have to remove the two Injector Housing Coolant Manifolds just to keep the aluminum shavings out of the coolant system.

Here we go again....if you do remove the Plenum....might as well remove the Ignition Coils and starter. You can then recondition the Starter Solenoid......and clean the Valley Drain.

[MuRCieLaGo]

Thanks Dynomite,

Is there any trick about that coolant thingy? Where is the drain bolt?

[Dynomite]

Bottom passenger side you can reach and feel it.....use a pliers and you can open it (unscrew it)

Radiator Drain

[MuRCieLaGo]

At first I unscrewed what appeared to be the oil cooler drain plug. Am I right assuming it was oil from the oil cooler? It is not far from the radiator drain plug.

[Dynomite]

Originally Posted by MuRCieLaGo

At first I unscrewed what appeared to be the oil cooler drain plug. Am I right assuming it was oil from the oil cooler? It is not far from the radiator drain plug.

Yes.....you drained your oil cooler?

Oh...well.....no harm and no foul.......just ad a couple quarts of oil to replenish what you drained out of the oil cooler.

[MuRCieLaGo]

Now I've got an oil leak from this oil cooler drain plug. Oh well, what a bad day.

If I continue tightening, the plug will finish in the oil cooler. I removed the drain plug and the threads seem to be perfect. Do I need to put some kind of Loctite?

[Dynomite]

Originally Posted by MuRCieLaGo

Now I've got an oil leak from this oil cooler drain plug. Oh well, what a bad day.

If I continue tightening, the plug will finish in the oil cooler. I removed the drain plug and the threads seem to be perfect. Do I need to put some kind of Loctite?

Be very careful....I have seen some discussion about that plug being a tapered pipe thread. I use permatex thread sealant on all pipe threads.

[MuRCieLaGo]

I really need help on that one guys... The threads are neverending I really am confused now.

[MuRCieLaGo]

There you go: drain plug is now inside the oil cooler.