C5 Targa rear squeak

[Krusty]

Can't thank you all enough for the support so far!
I have been taking the advice.
I am going to my friends in it tonight which is 23 miles each way and it has a mix of A roads, B roads and 2 major towns. So it should be good by the tine I get home I imagine
I've also used the silicone spray on all the rubber boot seals and so on that you pointed out. So more updates on that later...

Next on the list, this oil leak!
So whilst fiddling around, the engine has been basically running on and off over the last 2 hours on the driveway and I spotted a very thin stream of oil running like this


Again, I have checked the rocker cover seal for leaks but they're bone dry!
What else is up here that could cause an oil leak?

Cheers

 

[teamzr1]

You're Welcome

The PCV itself is inserted into that rubber boot. There is a ground clamp around the boot and then bolts to the block
Make sure metal clamp has not cut the boot
Make sure you shake the PCV, it should rattle and be sure it is not sticking open
Use good light and see if you can tell is leak is right before or after the PCV rubber boot
Maybe it is cocked inside the boot so not clearly sealed or boot is damaged or
that back side of the boot connected to the hose that goes to valve cover area is not fully sealed
But clearly that is where the leak is, so you will have to closely look from hose to throttle body connection
as where the issue is

As to hatch noise, if silicon does not help, check the other points I mentioned or as I state
buy a kid some ice cream, (or the wife) throw them in the hatch and while driving see if thy can locate where the noise is at

 

[teamzr1]

With good light, should be able to tell if leak is back end of PCV boot or elsewhere in that area

 

[Krusty]

Small update: I still haven't had a chance to drive my car due to other commitments, plus also the weather has been pretty poor the last few days here.
I did manage to do yet another check regarding this oil leak and can confirm that the rocker covers are DEFINITELY not leaking.
Also the PCV system is DEFINITELY not leaking.
However, I did manage to trace the oil further. I found it has been running from the other side of the motor (behind the power steering reservoir), along the front of the inlet manifold/under the throttle body and down to where I initially said here that I'd found the oil 'pooling'.
I have found a very oily pocket right at the front of the motor, located behind the power steering reservoir. It is certainly engine oil and not PSF (just to save anyone asking the question) and I now believe this leak could be coming from the 'valley cover' gasket located under the inlet manifold itself.
I have cleaned ALL of the oil residue that is visible and I aim to drive the car tomorrow for a couple of hours to let the MAP sensor relearn (as teamzr1 suggested in a previous post). So I'll keep you all further updated if the oil returns to the same place I have traced it to AND if the squeak has gone also
Watch this space

 

[Krusty]

First proper dry day in weeks!
Got out for almost 50 miles, the car drove awesome and my mpg has certainly improved now that the MAP sensor is reconnected

Oil leak, I'm pretty positive it's coming from the valley cover

Squeak, STILL REMAINS!!!!
However, a new development. Very VERY rarely I can compress the rear suspension and am able to replicate the sound very quietly... not always! But it did it today so I jumped at the opportunity.
I had my friend with me and had him compress the rear suspension over and over again whilst I had a listen and poke around under the car.
It sounds like the exhaust may be the problem because the sound can be heard through the rear wheel arches, on both sides.
Whilst under the car (with what very little room I had to work with at the side of the road), it sounded more and more like it is coming from where the exhaust routes over the rear axle!
I did get the squeak to stop when I put pressure on the exhaust in very particular ways. But again, I am quite limited on what room I had to inspect it whilst at the side of the road and even back at home... so I need use of a 2 or 4 post ramp now to diagnose it further.
I do honestly believe my exhaust is the problem, where it routes over the rear axle. Which will also explain why I thought it was an interior squeak when it's really been the highest point of the exhaust underneath, at the rear (if that makes sense).
It also explains why the squeak is noticeably loud OUTSIDE the car when I've been travelling through towns with tall buildings to rebound the sound back easily.
So my next question is (before I go diving in to it blind), is there an exhaust hanger located above the rear axle Or around there somewhere? I couldn't see one whilst under it earlier... but I genuinely had very little, limited space to do a 2 minute road side diagnosis

Thanks

 

[Mr. Cricket]

I'm not too far and have a four post if it'll help put this saga to bed and yes lovely weather today

 

[Krusty]

I'm not too far and have a four post if it'll help put this saga to bed and yes lovely weather today

This would be a HUGE help
Can you message me and we can arrange something?

 

[teamzr1]

I mentioned this back in post #3 and is a well known issue

As you see with my C5 in the stock mid-pipe next to the H pipe you see the 2 brackets
You could silicon spray those and also look at the hangers of mufflers and look at the rubber grommets and silicon those where you're at it
Re torque any bolts or hangers
Notice the muffler hangers sticking up the rear of mufflers in my image

 

[Krusty]

I mentioned this back in post #3 and is a well known issue

As you see with my C5 in the stock mid-pipe next to the H pipe you see the 2 brackets
You could silicon spray those and also look at the hangers of mufflers and look at the rubber grommets and silicon those where you're at it
Re torque any bolts or hangers
Notice the muffler hangers sticking up the rear of mufflers in my image
View attachment 20836

Yes I do remember you saying and I did do all exhaust checks back when I had use of a ramp, but I couldn't replicate the sound back then.
Again, the squeak is very hard to replicate when the vehicle is stationary. It only happens when it is in motion and it very loud when you're sat inside the car! So it doesn't matter how much I pull, push and prod everything. I am wasting my time until I get that 1% chance that it actually starts again, when it is stationary.
the very few times that it has made the sound whilst stationary, I have been on my own and I physically can't push on the car AND search for noise at the same time to replicate it... I have always needed a spare set of hands.
Yesterday I got EXTREMELY lucky that my friend was sat in the car with me when I was able to finally replicate the sound
With the limited space I had at the side of the road, I couldn't see or feel high enough for any hangers, possible contact from the exhaust with the body or anything else.
Now that I can see the next hanger along is on the H pipe, I'll be sure to inspect, clean, give everything a bit of lube and re-torque whilst it's up in the air... also checking the exhaust clearance as it routes over the axle (just in case).

Typically, the snow has fallen here overnight so I will have to yet again put it on the back burner for now and update you all when I can get the car out again

p.s. I've been thinking of replacing my stock H pipe for an X pipe... are they really worth doing? I understand it will smooth the balance of the exhaust flow.

 

[teamzr1]

I think if you're getting a chance of getting the car up on a lift to silicon lube spray to all grommets and bushings of suspension (front & back) such
as for A-arms, shocks, swaybar end links, exhaust, etc

If you want the hard techie detail on use of an X-pipe and best placement, read my long term design and testing of them

Team ZR-1 X-Pipe project

We decided to make our own exhaust X-pipe to replace where the CATs go for when racing. To me the X pipe should be close to where the bends are that trap gases and not further back where pipes are straight. We also made slip flanges for the CATS so they can be easy swapped with X-Pipe ...

www.teamzr1.com

 

[Krusty]

Update

Oil leak is now sorted
Valley cover gasket was the culprit.
The good guys at PartsUSA in Bredbury helped me sort that one out

Hoping that is the end of all the oil leaks


Why it was there, they put my car on the ramp to locate the squeak and it seems the problem is the 2 spring brackets located at the H pipe.
They're very rusty and lubricating them only quietened the squeak a little, until it fully returned within a mile of driving.
GM Euro want £90+VAT PER SPRING!!!!! which they can sod off!!! That's extortion at its absolute finest.

I'm still convinced it is rubbing on the body possibly as it goes over the transaxle... but I'll need more time than they had available to inspect it properly.

 

[Mr. Cricket]

you'll miss that squeak when it's gone

 

[teamzr1]

They lubed the center of springs but not the ends of them where they mount and could squeak from there ?

 

[Krusty]

They lubed the center of springs but not the ends of them where they mount and could squeak from there ?

They had a quick look for me.
There wasn't enough time available to get stuck in and definitely source the squeak.
The spring is made up of 2 springs (1 inside the other) and with it being so rusty, you could hear them squeaking away quite easily.
However, the squeak wasn't as bad as when the car is sat on the floor!
Yet again, it was really difficult to replicate the sound.
It is so loud when the car is settled on its 4 wheels.
Once it's up in the air on a 2 post ramp, you're very lucky to get it to squeak even a little
So I'm genuinely convinced about it being the pipes as it goes up and over the transaxle.

I think the next step is going to be putting it on a 4 post ramp so it stays settled on its wheels and really pulling on everything from underneath until the issue reveals itself. Then deal with it from there.

I'll report back with what I find, when I can find a 4 post ramp to use
Hoping Mr Cricket will still offer me his

 

[teamzr1]

Each muffler and pipe over the half shafts have the mount at that spring hanger and then at the side of the muffler
So not sure how the pipe back there would be causing a squeak
Unless the couplers at each end are loose or bad gaskets

 

[Mr. Cricket]

They had a quick look for me.
There wasn't enough time available to get stuck in and definitely source the squeak.
The spring is made up of 2 springs (1 inside the other) and with it being so rusty, you could hear them squeaking away quite easily.
However, the squeak wasn't as bad as when the car is sat on the floor!
Yet again, it was really difficult to replicate the sound.
It is so loud when the car is settled on its 4 wheels.
Once it's up in the air on a 2 post ramp, you're very lucky to get it to squeak even a little
So I'm genuinely convinced about it being the pipes as it goes up and over the transaxle.

I think the next step is going to be putting it on a 4 post ramp so it stays settled on its wheels and really pulling on everything from underneath until the issue reveals itself. Then deal with it from there.

I'll report back with what I find, when I can find a 4 post ramp to use
Hoping Mr Cricket will still offer me his

Yes mate no problem. I even anchored it down last weekend so even though they said no need to, it's better in my eyes now

 

[Krusty]

Each muffler and pipe over the half shafts have the mount at that spring hanger and then at the side of the muffler
So not sure how the pipe back there would be causing a squeak
Unless the couplers at each end are loose or bad gaskets

View attachment 21148View attachment 21149

It is a Borla back box system bolted to the stock H pipe.
Again, I didn't have much time on the ramp and they where kind enough to let me give the car a quick look whilst in the air.
I gave the exhaust a really good shake and pull. The most obvious sound came from the spring hangers which I admit are very rusty and the squeak was very noticeable from them... although I still wasn't fully convinced because the system still had little squeaking noises coming from the pipes as they route over the transaxle.
That's as far as I got because I couldn't take up any more of their time!
They have been absolute legends today helping me with my oil leaks and being a quick set of extra eyes, but I definitely need a good amount of time to study the system properly and preferably on a 4 post ramp so I don't disturb how the car sits.
As soon as I lift the car off its wheels, the noise 9 times out of 10 goes away until I drive it a few miles and it will eventually return once everything has settled again.
It really is an odd one haha

 

[Krusty]

Yes mate no problem. I even anchored it down last weekend so even though they said no need to, it's better in my eyes now

That's awesome. Can't be too safe as they say...
I'm available this Thursday all day, Friday afternoon, Saturday and Sunday all day, plus all next week if you'd like to inbox me a time best suited for you?
You'll be able to hear exactly what I mean when I pull up... you'll think the car is a bus

 

[Krusty]

Hi everyone.
Another quick update...
I took the rubber hangers off the very rear of the car on Thursday. I absolutely smothered them with tons of copper slip grease! along with the metal part that slides through the rubber hangers to hold up the silencers.
I have just been to a little, local car meet today (and spotted a C6), also went for a really good drive to my friends pub with a few mates.
We've belted along lots of fast A roads and tight, bumpy B roads... I've honestly not had a single squeak!!! I've covered well over 50 miles.
Looks like I've finally solved it
What a journey eh! haha.
Lets hope it doesn't come back
It looks like I have solved all of my oil leaks also




Cheers everyone