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Discussion Starter #1
Sorry for the long story....I just want to give you guys as much information possible. So I finally completed my coolant transfer pipe / weep hole leak repair. Coolant system was pressure tested before I put everything back together. I replaced all of the intake gaskets (8 on the TU engines) and put it back onto the mounting studs.

That's where the trouble began. The manifold was not sitting flush, it rocked just a tiny bit, I wrote it off to the gaskets not all sitting at the exact same level. The nuts were torqued in 2 stages, crisscrossing per my tech buddy/assistant. Everything else was reinstalled and I got ready to fire it up.

Turned the power on (did not start it) so the fuel rail could prime and the Vanos motors initialize. Waited for everything to stop making noise and turned off for about 30 seconds. Fired up the engine and pulled out of the garage and let it idle for a minute to get oil moving since the car sat for a few weeks. I set the date and time and shut off before adding some water to clear the low coolant warning.

I started the engine again and started to give it a few revs. Throttle response felt sluggish and I hear hiss/whoosh sound when I pressed the pedal harder. Check engine light is on the dash, but all other warnings are clear. It is pretty obvious there is a vacuum. So far I tried a few squirts of carb cleaner around the base of the intake manifold, but could not get any clear indication of the source. I do not have a scanner to pull codes.

Worst case my Indy is about 2 miles away. Any input or suggestions would be much appreciated. I'm just a bit frustrated after getting this far and running into a vac leak. Thanks for listening.

Jason
 

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there are not many vacume hoses ,, if you can here a Hiss ,,check the CCV vacume hoses .. Possibly could be cracked or broken or disconnected . Had the same thing happen to me at start up ,, I was crying like a new born .. All kinds of things popped up , check engine malfunction , emissions errors . Car shook violently felt like the car was having a seizure.. fixed the the broken driver side vacume hose ,, then she purred like a kitten . even if you pull codes right now ,, you'll get miss fire codes and emission codes . Make sure and take care of that vacume leak then go from there ...
 

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H_F,

First thing, I just want to thank you. Your posts have been super helpful since I joined in March. You are willing to jump in on anything N62/Tu, even if you have answered it before. So thanks for sharing.

The engine is not running horribly. If I rev high enough it stops and the valve train gets quiet. So maybe it's just a tiny CCV connection leak. I tried a quick shot of carb cleaner on all 3 connections and it may have quieted the valves again for a second. Too late to go back out and rev the engine some more. I missed that sound :)
 

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You are more than welcome Sir,, happy to help .. And welcome to the forum ..

Did you install new or take a look at the CCV diaphrams on the valve covers ? A big enough rip in the rubber will also give u a vacume hiss and what you're experiencing ..
 

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Discussion Starter #5
So I pulled the 3 CCV connections and made sure they were seated properly. I also missed a cam sensor connection on the passenger side. Started up and gave it a few revs. Same thing, still sucking wind. But it might not be quite so bad, could be my imagination. I went around the block and the car drives alright.

Can I drive it this way for today just to get to my parents and back? About 15 miles each way. I just don't want to run lean and burning anything else up. Or kill the cats. Thanks
 

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Check the dipstick. You might have dislodged it and completely forgotten about it, Also I'd think the manifold should have been seated correctly, without movement, I'd double check that. Easiest solution is to use a smoke machine really.
 

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Discussion Starter #7
So far it is a confirmed crack in the CCV hose. Ordered a new one. Hopefully that is the only leak. No dipstick on the 2008, but the dummy tube and handle was in the way of intake manifold connectors!
Thanks
 

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So far it is a confirmed crack in the CCV hose. Ordered a new one. Hopefully that is the only leak. No dipstick on the 2008, but the dummy tube and handle was in the way of intake manifold connectors!
Thanks
I had similar whooshing sounds. My CCV hose was cracked at both connections, under there tape. I'm doing my coolant pipe this winter, seriously not looking forward to it
 

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So far it is a confirmed crack in the CCV hose. Ordered a new one. Hopefully that is the only leak. No dipstick on the 2008, but the dummy tube and handle was in the way of intake manifold connectors!
Thanks
Are you sure about no dip stick ? as far as I know the V/8 have dip sticks.

On the cracked hose ,, get some shrink wrap . Heat it up and that will fix the leak . Thats how I fixed mine on the spot . And actually I never replaced the hose and called it good... Its held up quite well over the years . But I forgot to mention ,, i installed a air hose splice fitting in between and then shrink wrapped it .
 

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The new CCV got here and I installed it last night. I also rechecked the air filter and clamps to make sure everything was snug. Started it up and it is still hissing/sucking air when I rev the engine. :mad:

I am going to try and convert my garden sprayer into a fog machine with some dry ice and pump it through the manifold. Hopefully the leak will reveal itself. I really don't want to pull the manifold off again.
 

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The new CCV got here and I installed it last night. I also rechecked the air filter and clamps to make sure everything was snug. Started it up and it is still hissing/sucking air when I rev the engine. :mad:

I am going to try and convert my garden sprayer into a fog machine with some dry ice and pump it through the manifold. Hopefully the leak will reveal itself. I really don't want to pull the manifold off again.
you could use a plastic/metal bucket with a tight lid + soldering iron (cheapest kind) wrapped in steel wool and dipped in oil. a couple of small tubes and your ready to go.
 

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Discussion Starter #14
Looks like I am just going to pull the manifold and make sure everything is seated properly. I might even throw some permatex around the edge just to be sure.

Overall the pipe replacement was not too bad. It took me about 10 hours working a little bit every night after work, and no special tools other than a torque wrench. Having a friend to help get the manifold up and out is a nice luxury.
 
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