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Tire abuser
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Discussion Starter #1 (Edited)
After my car warms up ('06 Elise) it has a continuous "squeal" or "whistle" coming from the throttle body area. It is annoying. The idle seems OK, maybe a little slow to drop, but the car is running fine. The noise goes away as RPM is increased.

Last night I was poking around at the vacuum hoses and spraying some no-residue contact cleaner on different spots without success. Finally, I sprayed close to the fuel rail and the idle changed. Repeat, same thing. Does this indicate a possible leaking o-ring at the injector? Would it suck in there without leaking fuel out?

One last question.... Might that give me a squealing throttle body, or is that probably unrelated?
 

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I've seen where the supercharger can break a stud at the far end of the manifold, farthest from the belt, and that will cause a loud squealing sound, which is the mechanical noise of the supercharger. It might be that when you sprayed the fluid near the injectors it was actually going in the gap between the supercharger and the manifold.

Or it could also be that the fuel injector o-ring is leaking. Worth checking.

At idle you have vacuum, so you wouldn't see the fuel coming out, but you might with boost.
 

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I had an isolator dryout which is the rubber o shaped washer that goes between the injector and the head. The o rings are between the injector and fuel rail. This isolator was not sealing fully and was causing a fluctuating idle as unmetered air was getting by. Really easy fix, pull fuel rail out without removing injectors. Replace 4 isolators and reinstall fuel rail. Tommy
 

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Tire abuser
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Discussion Starter #4
Ah, very helpful! Thank you both for the posts!
 

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I have had O-rings leak on my Elises injectors. At idle they leak and you can definitely smell fuel. Sometimes you will get a code and sometimes you don't. Mine is supercharged also.
 

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General it is common when replacing injectors fo s/c applications to replace upper o rings. Sometimes one will roll when connecting to fuel rail. If u smell fuel u should replace o rings. Use some lube when installing as they are tight. U also can double them as the groove has space. The isolates at the bottom of injectors dry and crack due to heat. The new ones i bought from toyota were a fix for this. I will get new part no. The rc injectors are good but the bosch ones tended to roll on install. Tommy


Sent from AutoGuide.com App
 

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Here u go part no 23291-41010 insulator injector. Tried to upload pic but got some sort of domain error


Sent from AutoGuide.com App
 

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Tire abuser
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Discussion Starter #8
Thanks for all the help.... but you guys will NOT believe what I found! I stopped by a dealership and bought new insulators and o-rings for the injectors. Removing the fuel rail and injectors was super easy. Then I noticed a nut missing off one of manifold studs! There are 5 studs that hold the intake manifold on and here is the condition they were in starting from the right side of the car:

1. Completely missing
2. Finger tight
3. Nut missing
4. just snug
5. just snug

Basically, my manifold and supercharger were about to fall off. Amazing that the car really ran quite well. Some new hardware and loctite.... much better! It was an easy fix, but wow everything is better now. Less vibration, more power, etc.... Makes me want to re-torque everything on the car.
 

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It's not the first time!

Having only 5 studs holding the manifold might be fine, but add the weight of a supercharger and the force of the tensioned belt!!!

I think BOE has a brace for their supercharger to keep from breaking studs.
 

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shay2nak
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I should check this on my car. I don't have any squeals or whistles, but maybe it's worth a look since it's close to the knock sensor.
 

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Yes quite common if loctite was not used. also use good lockwashers with the nuts. My bolts on the swan neck to s/c also looseded up. I locktited those as well as adding studs to the top 2. Check everything. Glad it worked out.
 

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I'm glad you got it sorted! It just didn't seem like and injector o-ring issue to me. Just in case, you can get a set with an o-ring and bottom seal for your injectors at most auto parts stores. Some sell them for one injector and others sell a 4 unit set depending upon the store. I keep a full set as spares just in case.
 

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Tire abuser
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Discussion Starter #14
Do you have a part # for the insulators and o-rings for the injectors?
Thanks!
I don't... but at the dealership I told them that I had a 2006 Celica GTS and the parts were fine. There was a young guy waiting at the counter and he had a Celica. He thought it was really cool that I had the GTS. You could tell he was pretty jealous.
 

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Tire abuser
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Discussion Starter #16
Hey HK,

If you are asking about my situation.... I was missing bolt 11 and the nut off of stud 8.
 

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Hey HK,

If you are asking about my situation.... I was missing bolt 11 and the nut off of stud 8.
Just wonder, after removed the inter-cooler:
- Can we see or feel those 5 bolts and nuts by finger?
- Can we tighten those 5 bolts and nuts without removing other parts?

The reason that I ask is because dealer told me that need to take off the supercharger to check or tighten thost bolts :scratchhead:
 

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I have recent familiarity with those fasteners. I don't see how you can get to a couple of them without tinkering with the SC?
 

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I have recent familiarity with those fasteners. I don't see how you can get to a couple of them without tinkering with the SC?
After un-install the cooler:
- I can only see bolt #10, #6
- Feel bolt #11 and #7
- Can't even see nor feel #8

I guess without un-install the SC nor lossen it, there is no way to tighten nor check those #8 & #11 bolts.

To un-install SC, may need O rings, gaskets, or even loosen up sub frame.

Correct me if I am wrong.
 

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Loosen up sub-frame?? (confused)

If you are going through all of the trouble to remove the supercharger, it would be a great time to wrap it up and send it off to be ported & polished by a reputable shop. You will feel the difference.
 
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