Re: TB coolant crossover,any disadvantages?
 

Marc says 20' F, 90% RH.

Under those conditions, I bet with hammer down (high velocity through the TB), you'd be GUARANTEED icing.

At light throttle, who knows. I'd be interested in the test procedure parameters...

Re: TB coolant crossover,any disadvantages?
 

Marc knows ;)

I would guess Marc drove the Z at all throttle positions for a test proven period of time at ambient 20 deg F with 90% humidity (the 90% humidity is pretty severe regarding icing).

Marc uses the bypass to make sure no one will come back and suggest a coolant filling technique failed because of his TB coolant elimination.

the throttle body has no problem with ice when the ambient temperature is at 20 degrees and the humidity is 90%

Marc bypasses TB coolant and I eliminate TB coolant with NO bypass with my coolant filling technique that absolutely eliminates the potential for an air locked water pump.

See Getting the Air Out Simplified TIPS

Re: TB coolant crossover,any disadvantages?
 

Thanks, yea I've been reading up on all this stuff trying to decide what to eliminate and what to leave I got confused about the vacuum line.

I was having an idle issue so I pulled the plenum. Didn't find any obvious vacuum leak. All of the plastic hoses and rubber couplers look good.
I'm going to put wire ties and silicone on all the connectors and rubber hoses.

Had my injectors flow tested, four bad injectors. Ordered new injectors from FIC.

Decided for now to remove the TB coolant hoses to dress up my polished plenum.

Re: TB coolant crossover,any disadvantages?
 

If the vacuum pump is turning on and off with the key on say every 10 seconds more or less (the vacuum pump if no leaks will actually turn on for a few seconds and then shut off for several minutes) you have a vacuum leak.

1. With plenum off disconnect the vacuum lines one at a time starting from the pump and hold your finger over the end of the vacuum line. The pump should shut off and stay off.

2. Now go to the next suspect connection and do the same.

3. Once you get just past the leaky connection, holding your finger over the end of the vacuum line will not stop the pump from recycling. You have now found the leaky connection :thumbsup:

Usually the rubber connectors leak from age (hardened rubber).

Re: TB coolant crossover,any disadvantages?
 

What do I do about the fuel pump coming on with the key on and the plenum off.
I was going to check the secondary actuators but I thought about the fuel lines being off.
Oh yea, I'm new at this.

Re: TB coolant crossover,any disadvantages?
 

Actually I think you can leave the fuel lines connected to the fuel rails and still remove Plenum.

You can check all vacuum line connections by just tipping the plenum up in front without disconnecting any DIS connectors or vacuum connections at rear of Plenum.

Re: TB coolant crossover,any disadvantages?
 

Yea but I've got mine all apart to replace injectors.
I'll check that after I put the new injectors in and connect the fuel line.

Re: TB coolant crossover,any disadvantages?
 

OOPS :D

Excellent point on turning on the key with fuel lines disconnected :thumbsup:

Oh...if you have fuel lines disconnected from the fuel rails they tend to leak fuel as fuel tank pressure (Vapor Pressure) changes in the fuel tank.
Loosen the Fuel tank cap to solve that issue.

Re: TB coolant crossover,any disadvantages?
 

I loosened my cap here Cliff, after making the same mistake on the Z, that I did with the LT1 - cap ON, and scary smell of gas on the second day (I was afraid to do anything that day even).

Cap OFF on the Z didn't get it. 4rth day, more gas :mad: :censored:

I ended up dis-connecting feed + return lines @ the tank.