Opti vent harness check

[BALLSS]

1Slow..

appreciate your comments and yes if the vacumn reading at bottom of line with blue valves is 18 and if only 4 on the nipple at intake elbow that suggests the "Opti" itself is not sealing

I will search my FSM to see wtf it has to say about checking and if 18 in of vacumn is what we should be reading from the blue nipple and not 4.


Also it appears the blue/white valves are not "restrictors" but directional meaning they only allow fow one direction, right?

maybe you or someone who has a vacumn gauge can check wtf their vacumn is at blue nipple with hole in intake elbow plugged??

[1slow96]

My understanding about the blue/white valves is they control direction,and rate of flow. They also control how quickly the vacuum inside the opti goes up,and down as compared to vacuum inside the intake manifold itself. They are both important,the most common problem seems to be putting one of them in backwards.This will ultimately lead to an opti failure.

[Marky Dissod]

Opti-snorkel info
More Opti-snorkel info

[BALLSS]

Originally Posted by BALLSS

I will search my FSM to see wtf it has to say about checking and if 18 in of vacumn is what we should be reading from the blue nipple and not 4.


??

FWIW I did look in the FSM "Distributor Ventalation System" 6D4-7 &8. While it does not give specific vacumn" specs it states vacumn at blue nipple on "duck, air intake" should slowly build and = manifold vacumn.

Mine does not as it goes to 4" not 18"-19".

It would appear the brand new Delphi Opti does not seal very well. I did remove cap to put loc-tite on rotor screws and replaced. Maybe it needs some form of "sealant"

or is there opinions that 4" is enough vacumn to purge moisture and gasses?

I do know a non functioning vent harness will kill Optis in as few as 500 miles as the dealer replaced 3 in a row back when my car was under warrenty....I later discovered a blue/white valve was reversed by Mr Goodwrench. I bought the car back to the dealer, they removed Opti and green crud flowed out. Have not had the problem since check valves are in correct position

I am chasing a stumble under load problem and after replacing opti, vent harness, plugs, wires, ICM, coil, injectors, MAF, MAP, EGR & solonoid the problem still persists......wondering if the possible 'leaking" vacumn through Opti is the culpret??

Either case I will have to pull Opti just to seal it to hold vacumn before crud builds up in it.

[1slow96]

Seems to me the vent. harness pulls the same amount of air into the intake regardless if the opti leaks or not. I wouldn't open up a new opti just to put loc-tite on the rotor screws,but that's me. I will do that if I've got one apart. Some like using RTV, dielectric grease seem just as effective to me. A little bit on the seals should do the trick.