Write-Up: EGR Tube Gasket Fix for "Tick, Tick, Tick"

Here's an easy fix for something that's been bugging me for ages: that faint ticking sound that can be heard at low RPM under load. If you've never removed the EGR valve or rear exhaust manifold, you probably don't have this issue, but if you've ever installed headers, removed the manifold, or the EGR, you might hear it sometimes. A good test is to brake torque while in drive. About 2k RPM is where you'll hear it. Confirm with a mech's stethoscope and funnel attachment.

IMPORTANT: if you identify a ticking sound from this area and have never removed the EGR or rear exhaust manifold, it's quite possible one of the EGR tubes has cracked and is leaking (this happened to me a while back). If this is the case, the gasket fix outlined in this write-up will not solve the issue. You must replace the tubes and cast iron base for the EGR valve. Not a difficult job, and it's probably a good idea to install the gasket as well.

In my case, there was some soot visible at the site of the leak:



The problem is, it's difficult to get the EGR tube seated perfectly against the flange on the manifold, and the flange screw is hard to access with the crossover pipe in the way. This is probably why some of us are hearing the tick - if you wait to install the EGR last, after the crossover pipe (the natural order), it's almost impossible to get that screw really good and tight. Because the crossover pipe isn't the easiest thing to remove, it makes sense to take another approach.

This job will take about 15 mins to make the gasket, and about 1/2-1hour if you have the right tools. If you don't have a set of crowfoot wrenches, now is the time to pick up a set.

STEP 1: Obtain an EGR gasket and create a template. I did this a few nights ahead. The gasket is only a couple bucks at the local parts store.



Also in the picture is a metal plate that clamps to the flange on the manifold. I used this as a template to create the gasket. If you don't have an extra one of these, here's a line drawing you can print out to scale. If you can't get it to work, I can send you a hard copy in the mail - let me know.



STEP 2: create the gasket. Use the template or trace the actual plate and cut out. Note to use the existing hole in the gasket - it's the correct size for the tube.





Drill out the hole for the screw:



Finish on a grinding wheel:



STEP 3: Loosen the screw clamping the plate to the flange. First apply a little PB Blaster penatrant to the end of the screw. I worked on the engine cold and had no problem breaking it loose. You'll need to use a 1/2" open (or flare) crowfoot wrench, 3/8"M to 1/4"F adapter, 1/4" med extension, and 1/4" ratchet. Here's what the tool looks like assembled.



Here's where the tool goes. Not a lot of room, so it's nice to use a small 1/4" ratchet.



With the screw removed, the plate should free up from the flange.



STEP 4: remove the 2 screws holding the EGR valve to the engine. These are pretty easy. Use a 13mm short socket + small 3/8" extension & 3/8" long ratchet for leverage. This will allow you to pull the EGR tube out of the exhaust flange.



Now unplug the EGR valve electrical connector and pull the EGR up and forward with a little force. The tube should come out of the flange.

STEP 5: install the new gasket around the end of the EGR tube, where it connects to the manifold/header, then reinsert the tube into the flange.



STEP 6: tighten the screw, clamping the gasket between the plate and flange. I tightened as tight as possible with the 1/4" ratchet. There seemed to be a point where it compressed the gasket, then became solidly tight.



Finally tighten the 2 screws holding the EGR to the engine. ALL DONE!

If for some reason the tick doesn't go away, you might try reinstalling the gasket with a liberal amount of high-temp copper RTV. I didn't need to, so I don't think it will be necessary.

Hope this helps a few of you solve your noise issue!

I will definitely try this during the summer. I think this is my problem

Mine too. At first I thought this noise was my axle (because of some past experiences) but the axle wasn't the problem. This is pretty much the noise I'm hearing, in the same RPM range and conditions. Looks like I have some tools to buy...

Thanks Aaron

Use a steth to be sure. For the money it's positively one of the top 5 tools I own.

Yep it's on my list of things to buy. I just got a nice digital caliper so a nice scope is a must.

This is the one I use. Highly recommend:

http://www.amazon.com/Lisle-52750-Stethoscope-Kit/dp/B0015DLMOO/ref=pd_sbs_auto_1#productDetails

Nice write-up. One thing/point I would add is in regard to the EGR tube itself. By adpating a gasket you are fixing issues with sealing along the mating ridge/lip of the EGR tube. One place that all our tubes are prone to leaking is just on the other side of that sealing ridge. The tube is soft and when you crank down on the coller it can tear on the "tube side" of the little lip. Adding some gasket to the face won't really fix that specific tear very well. If you find a tear such as that I'd reccomend repair by brazing, or JB weld. Then use an adapted gasket so you don't just tear the mating lip again when tightening.(It takes some of the strain off and helps pack around the trouble spot with the support of a graphite crush gasket.)

These sealing issues all come down to the design of the EGR tube where that thin lip is soft and is supposed to provide the seal. (once. Its not really supposed to be a reusable part.) The coller is just supposed to hold the lip compressed against the opening, but not provide any sealing in of itself. Its those design aspects that makes it prone to it cracking/tearing under use and movement.

Good points. I should mention the first time I had a ticking sound from the EGR, it was actually a crack between the accordion-style flex ribs. I replaced both tubes with a near new version from Ed Morad. I noticed the new tubes seem more flexible with less sharpness in the ribs. In my most recent case only the tube's seal was leaking, but in some situations it could be the tube itself is cracked.

(will add a note to the original post above)

I was posting in another thread about this ticking situation. I'm not running an EGR but I kinda like this idea just for the block-off plate because my problem is something having a gasket would probably help. I hate the design of this thing. It definitely should have had a 2nd bolt on the opposite side. Anyway it stopped ticking on its own it seems like but if it comes back, I'll give this a try.

It's SO nice driving the car now with that noise gone. Really lets me appreciate the header wrap more - makes the headers much quieter!

AA wrote:

It's SO nice driving the car now with that noise gone. Really lets me appreciate the header wrap more - makes the headers much quieter!

Isn't it nice? That's the main reason why I wrapped mine on initial install. All you guys who said it ticked a little....
You can't even tell it has headers (anymore)

Yeah, I can't remember it ever running this quiet since it had stock manifolds. I had bare headers for a while, which sounded okay, but the braided flex pipe ticked. I wrapped the flex pipe and that helped a lot. Then my EGR tube cracked at some point. Replaced it and wrapped the headers last summer. Quieter, but there was always a tick from that tube not sealing correctly.

I had a mad tick from that EGR pipe when I first installed the headers. I just used a piece of the crappy "header" gasket they supplied (which I didn't use) and some of the Red RTV. Hasn't made a peep since.

Question - I'm looking to get new EGR tubes and GMPD, for instance, only lists one tube for the L67. Are they both the same, or can the same tube be used for both locations? Thanks!

I bought the replacement tubes at first, I think from RockAuto. They were like $5 and didn't fit right. I tried modifying them, but ended up purchasing a used GTP EGR assembly from Ed Morad. It wasn't very much, maybe $20-30. MUCH easier install!

Thanks Aaron I'll probably end up seeing if Ed has any good sets.

I liked that the newer replacement had slightly larger tubes, with wider accordion spacing, and an insulation sock shield - be careful with the shield if yours has one. It's brittle, so touching it with tools or hands can cause damage!

So I guess I should try to get something from a newer L67, like 2000+?

I have one of those shields on my Series I. Luckily it's not brittle but I always have spares  .

I tracked down new EGR bracket and tubes. When I install them I'm definitely using your gasket trick Aaron. I'm suck of hearing 'card in a bicycle wheel' sound.