Hey guys, new here! I just recently got a 87 C4 with the doug nash - in pretty good shape and runs well until yesterday.

My EGR tube popped off while driving - sounded like a tractor. I managed to get it reconnected today using a hose clamp because I don't have the crimp tool.

Now, it still sounds like there is some type of exhaust leak - its definately less loud than when the tube was off but it almost sounds like a manifold leak now - almost no exhaust sound like before.

I havent pulled off the tube yet - is it possible the tube itself is cracked now? Or could this type of leaky sound be from the EGR valve (clogged and caused too much pressure making it pop off?)

If I were to delete the EGR entirely, how would I do that? I'm also ok with just buying all new EGR components and fixing it.

Im also wondering if its an entirely different leak... but since it all happened after the EGR tube came off I think its all related.

Any suggestions on how to move forward would help. I'm new to working on cars and this was a project I picked up to learn - now I have something to do but since this was a bigger issue than anticipated ( I was working on maintenance stuff only) I'm a little stressed.

Thanks!

 

A hose clamp isn't gonna cut it.

You're gonna need a new ring and a crimp tool.

May as well do it the right way and get it over with...

 

[img alt="I found this at the bottom of the tube - doesn’t look like it was even tightened. Should I reuse this one?

I guess it’s entirely possible that the leaking noise is actually because it’s still not tight enough.

Would you recommend to now change out any of the EGR parts while I’m at it?"]https://cimg9.ibsrv.net/gimg/www.corvetteforum.com-vbulletin/2000x1124/f9d2a455_d905_4f82_a22e_ce71c3e995e4_93d 392af32915a12c2758cde7241c8cd03ecda3a.jp eg[/img]
I found this at the bottom of the tube - doesn’t look like it was even tightened. Should I reuse this one? I guess it’s entirely possible that the leaking noise is actually because it’s still not tight enough. Would you recommend to now change out any of the EGR parts while I’m at it?

 

Yeah, that looks like a new ring to me.

Somebody's been in there before for something and clearly never crimped it when they put it back together.

Can't think of any reason to have taken the tube off unless it was to remove the valve cover for something.

 

So it's entirely possible that its just leaking from where I have a hose clamp on it lol

Does it make sense to switch out any of the other parts of the EGR while this is off, from what I understand it's hard to take this clamp off in the future.

 

Well, also inspect the tube too, the corrugated tube on my 88 had a hole in the bottom of one of the pleats which was hard to see. I made the mistake of trying to seal it with the high temp JB weld without understanding that thing will get too hot from it and smoke like crazy. While you're in there of course you could do valve cover gasket if it needs it..

 

The voice of reason and experience right there!!

 

Is there any good way to plug the hole from the manifold myself without permanently welding it? I'm still undecided on wether or not I want to delete EGR as im getting conflicted opinions online on wether or not its good long term.

Ive been looking at just maybe getting a 88+ manifold and having the bolt on EGR tube as well.

 

I used a hose clamp (same crimp clamp) where air tube goes to muffler and it worked.
.

 

Is your service engine light one?

If not, and if it's running well as had mentioned, my thought is that it's probably best to leave well enough alone.

But the tube was removed for something.

As I said, the only thing I can think of would be to have serviced the valve covers.

Maybe whoever did whatever was done didn't have a crimp tool either and just said hell with it.

 

I don't have the crimp ring setup on my '90.

On mine the EGR pipe bolts to the exhaust manifold with two T-40 bolts and a high temp gasket.

I've been through my own drama with that EGR pipe myself.

All I started out wanting to do was change valve cover gaskets and sand and repaint my valve covers.


But...

https://www.corvetteforum.com/forums...ing-me-up.html

 

Omg lol

I've decided that I'm going to attempt to cap the opening on the exhaust manifold with a silicone coolant cap. Keep the tube attached on the intake side but plug the tube itself FOR NOW. I want to see if that will solve the issue and I can drive the car here and there. I need to find a plate that will fit the intake side if I decide to go EGR delete still.

I havent decided if I'm going to gut the entire EGR system because the plan is to get LT headers anyway, thats just way down on my list of priorities. I don't know enough yet to say I don't need the EGR for good... I just want it to stop sounding like a tractor and be drivable again.

I also need to see if there is ANOTHER leak somewhere, because when I did attach the EGR tube back on with the hose clamp, it still made noise... so not sure if that's because the tube itself wasn't sealed or theres another leak somewhere.

I have SO much other regular maintenance stuff that I want to get done before I start tinkering with removing emissions stuff and replacing headers, but I do want to drive it around the block here and there haha

 

So I actually managed to plug the hole in the exhaust manifold with a coolant cap - at idle sounds ok but with any gas in neutral or first gear there is another airy leak sound under the car now in the middle

From my understanding that hole I plugged isn’t under pressure but when I give more gas it popped even the cap off and back to square one.

What am I missing here? Everyone says to just block the EGR and all good or is there something wrong my with catalytic? No flow through it?

 

I wonder if my focus should be more on just getting the EGR tube back on there securely with a proper clamp instead of doing the capping.

im just wondering why I’m hearing another leak under the car when its capped off

 

My setup for the EGR pipe was like yours, but fortunately didn't experience the same challenges with getting out the torx bolts. One of them had been replaced with a hex bolt anyway. It wasn't until working on this car that I discovered that there were specialized bits for stripped torx bolts! Either way, after a day or two of them being soaked in penetrating oil while I did other things they eventually came off.

 

You should remove and inspect the EGR tube for cracks or warping. Check the EGR valve and ports for carbon buildup and clean or replace as needed. If you fix or replace the EGR components, the leak should stop. Deleting the EGR is possible with a blanking plate, but you may need Diesel Tuning or ECU adjustments to avoid check engine lights and maintain proper performance.