What is this part? (see pic - nipple and hose behind throttle body)

[drno4]

2003 Yukon Denali XL 6.0 (LQ4) w/ 185K miles

Replaced my throttle body and throttle position sensor yesterday, after our rig recently threw two codes regarding the TPS -- our TPS was riveted to the TB and I decided to replace the entire unit rather than haggle with drilling out rivets...

ANYHOW...this nipple cracked in the process (see red arrow in pic), with half of the plastic nipple remaining inside where it inserts just behind the TB and the other half of the nipple remaining in the hose that runs over toward the fuel rail.

Need to replace it, if possible...

But (1) is it molded to the intake, or can the broken remnant be removed? And (2) if it can be removed, what's the part and the specific hose? (pic is a screenshot from an unrelated video of what the nipple should look like intact)

TIA!

 

[Rollincoal]

Think it’s just a vacuum line man definitely need to get that fixed. Sometimes that nipple can be pulled out of the throttle body or even rotates.

 

[Rollincoal]

I have 5.3 in my yukon so probably same as yours

 

[iamdub]

2003 Yukon Denali XL 6.0 (LQ4) w/ 185K miles

Replaced my throttle body and throttle position sensor yesterday, after our rig recently threw two codes regarding the TPS -- our TPS was riveted to the TB and I decided to replace the entire unit rather than haggle with drilling out rivets...

ANYHOW...this nipple cracked in the process (see red arrow in pic), with half of the plastic nipple remaining inside where it inserts just behind the TB and the other half of the nipple remaining in the hose that runs over toward the fuel rail.

Need to replace it, if possible...

But (1) is it molded to the intake, or can the broken remnant be removed? And (2) if it can be removed, what's the part and the specific hose? (pic is a screenshot from an unrelated video of what the nipple should look like intact)

TIA!

I believe that's the fresh air inlet for the PCV system. That being open would present a vacuum leak, which would cause a high, possibly erratic idle and DTCs.

I think it's molded to the intake. If it is, I'd drill it out just big enough to be able to screw a hose barb fitting into it and slip the hose on that.


I'm not sure of the hose size, but I think it's 5/16ish:

LTWFITTING 5/16 in. ID Hose Barb x 1/8 in. MIP Lead Free Brass Adapter Fitting (5-Pack) HFLF39185205 - The Home Depot

This LTWFITTING hose fitting is made of lead free brass C69300 for superior reliability and strength. It is an adapter for connecting a hose to a male threaded pipe. And this pipe fitting can apply to

www.homedepot.com

...Or 90-degree if that fits better:

LTWFITTING 5/16 in. I.D. x 1/8 in. MIP Brass Hose Barb 90-Degree Elbow Fittings (5-Pack) HFLF3203605 - The Home Depot

Encapsulate an attractive addition to your kitchen space with the addition of this sophisticated LTWFITTING ID MIP Brass Hose Barb Elbow Fittings.

www.homedepot.com

These are 5-packs. They might be available as singles at Home Depot or elsewhere. On second thought, you might wanna go with a 5/16" (or whatever size that PCV hose is) with a 1/4" MIP instead of the 1/8". Just get whatever more closely matches the factory stuff.

 

[drno4]

I believe that's the fresh air inlet for the PCV system. That being open would present a vacuum leak, which would cause a high, possibly erratic idle and DTCs.

I think it's molded to the intake. If it is, I'd drill it out just big enough to be able to screw a hose barb fitting into it and slip the hose on that.

Thanks for your input and recommendations!

In talking with a local GM parts supplier in my area today, he affirmed that these nipples are molded (usually) as part of the intake...so to "replace" it would require replacing the entire intake. Having removed the intake on a previous job a few years ago to install a new intake manifold gasket and knock sensors, I'm not interested in going that route...

So, it seems my options would be some JB Weld and mastic tape (sounds unreliable, to me), or--as you wisely and more aptly suggested--fitting it with a new brass hose barb and, if needed, a hose clamp to cinch 'er up. I'll explore that.

Thanks again for chiming in and for your advice. I appreciate you!

 

[iamdub]

Thanks for your input and recommendations!

In talking with a local GM parts supplier in my area today, he affirmed that these nipples are molded (usually) as part of the intake...so to "replace" it would require replacing the entire intake. Having removed the intake on a previous job a few years ago to install a new intake manifold gasket and knock sensors, I'm not interested in going that route...

So, it seems my options would be some JB Weld and mastic tape (sounds unreliable, to me), or--as you wisely and more aptly suggested--fitting it with a new brass hose barb and, if needed, a hose clamp to cinch 'er up. I'll explore that.

Thanks again for chiming in and for your advice. I appreciate you!

It's not a high-pressure circuit by any means. Screwing in a hose barb, even letting it cut its own threads, should be a quick and easy fix. I'd screw it in, then back it out most of the way and put a healthy glob of J-B Weld Plastic Bonder on the threads and screw it back in. You might wanna stuff paper towels behind the throttle body to block plastic shavings from falling in side the manifold. Or, stick a shop vac with a crevice attachment in there while you're threading it. Support it securely while pushing the hose on. Use a little light lubricant on the barb to help the hose slide on, but nothing that'll make it easy to slip off.

 

[gooffeyguy]

Or if you do have a tap set, fill the flutes of the tap with grease to catch the shavings.

They make these fittings in nylon also available at any hardware box store. I would probably use that over brass just to lessen the chance the harder brass won't strip out the plastic intake if over-tightened.

 

[iamdub]

Or if you do have a tap set, fill the flutes of the tap with grease to catch the shavings.

They make these fittings in nylon also available at any hardware box store. I would probably use that over brass just to lessen the chance the harder brass won't strip out the plastic intake if over-tightened.

I didn't think about them being available in nylon. Good call! Tapping the hole beforehand and threading in a plastic/nylon fitting would be even better since the epoxy should bond to those materials better. Or, the threads in the nylon might end up being tight enough to not need the epoxy.

 

[drno4]

Thanks, friends, to all who offered good and encouraging ideas.

Was able to find some brass (and nylon) fittings and hose barbs (at Home Depot and Lowe's), but decided not to use them after all due to the risk, however slight, of cracking or damaging the intake manifold as I tapped or turned them in.

In the end, given the plastic PCV valve hose nipple broke around the round collar that connects it to the intake manifold, it still formed a decent mating surface to the molded intake. Therefore, I decided to keep and reuse the old part. Used JB Weld cold welding compound (P/N 8265 - rated at 5020 psi and 550 degrees heat resistant), and gobbed up the snot out of it. Clamped lightly for the first 4 hours. Let it cure for 21 hours total (recommended 15-24). Now feels hard as a rock. It's ugly but I do not care!

Also installed a new PCV valve hose (AC Delco P/N 12556932), as the old one was quite brittle and ripped open when trying to reinstall it on the PCV barb.

Lord willing, I think this fix should last for the life of the car.

Thanks again to everyone who chimed in. I appreciate you!

 

[MassHoe04]

Glad you found a fix (elegant or not)!
Even more glad for you not having to spend a lot of money or be off the road for very long.

Nice job!!