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high pitch whine sound after LIM and rpms

C

coldsteel

New member
Just finished replacing the LIM & UIM gaskets on my 06 grand prix, and when its running there is a high pitch squealing whining noise that sounds like a pulley or a vacuum leak. its not a pulley though. sounds to be coming from the right side of engine (#2,4&6). the car runs and drives, but it idles around 830-850 rpms. seems high to me. whats normal idle in park?would the fuel injectors make a vacuum leak noise if not seated all the way? what should I check that might be causing this? all hoses are attached, and I cleaned throttle body. I will try to get a vid for you guys
 


just got the code P0171 system too lean. I sprayed some ether around the injectors but didn't see a leak. I got a new gp Sorenson injector because of the broken one I had, Im wondering if this could be the problem.
 
ok thank you, I will try that first thing in the morning. would a faulty injector/seal cause this also? I pulled and installed the fuel rail a couple of times during the LIM repair due to a broken injector.
 
only if a o ring is leaking. if you oiled th eo rings each time you put them back in they should be good. and you sprayed then already right?
 
Also make sure the large vac line coming from the brake booster to the LIM is good and sealed. Mine didn't seal all the way when I did my LIM/UIM and I just bought a new fitting for the UIM. Solved the issue.
 


I sprayed ether around all the injectors and vac lines. The only spot I could tell a difference is when I spray around the egr valve and pipe itself. The egr pipe doesnt have a gasket at either end, which is what makes me think its leaking from there. The pipe wasn't cracked when I installed it. Is it possible to take the egr pipe out with the UIM on? It was a PAIN IN THE ASS to get the egr pipe in with the LIM on.
 
theres a small metal gasket that belongs there on the egr tube to lim, or tot he rear manifold. sometimes they stick to one side or the other, or it fell off on you.

high heat rtv should seal it up if its missing. and yes the tubes can come off lim on, theres always a chance the tube split when you pulled it out the first time, or when it went back in. seen guys rtv the egr tube, if that stops the leak you know the tube split.
 
I don't remember there being a gasket at either end of the egr tube. Even the one I pulled from a parts car, I don't recall a gasket. I got the TB off now getting ready to look closer at the pipe. I see the metal gasket that is on the valve itself, but none on the egr tube where it bolts to the LIM or egr valve.
 
could have sworn there was on on the rear pipe to manifold when i did my headers. if ones not needed it would have to be the tube split if when sprayed there the idle jumps up.
 


pulled the egr tube off, no cracks in it. switched it out for a different one I had. Put a hose clamp on the vac line ontop of the UIM to the air filter hose. Pulled out the large vac hose on the side of the UIM to the brake booster with the green o-ring, but my gasket set didn't come with a o-ring for that hose. It feels like it pulls in and out loosely of the UIM. I used some smoke to detect for the leak and its definitely sucking in at the egr tube to LIM. injectors seemed sealed. I want to put some rtv all around the egr where it goes into the manifold to see if it helps. here is what my fuel trim reading is now, Im trying to get it back to 0 or -.
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If I delete EGR tube will I get a code?
 
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You sould log LTFT (long term fuel trims), makes it easier to read.

If you delete the egr you will get a code, I'd just jimmy rig a way to seal the leak.
 
Ok ill try to seal it off once it cools down. But would a crack/air leak in the egr fitting or pipe even cause it to run lean and throw the the p0171 code? Isnt it sucking in air all the time anyway
 


Yea but would a leak in the egr tube make a difference to trip the p0171 code since its pulling air anyway from the exhaust? Im just trying to eliminate some possibilities.
 
I put rtv all around the egr tube where it goes into the LIM. Havnt got the code since and my fuel trim is staying under 5% most of the time. But I can still hear a hissing sound, sounds like an air compressor valve, around the egr/brake booster area and I cant figure out what it is.
 
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