EnclaveForum.net: Buick Enclave Online Community banner

1 - 6 of 6 Posts

·
Registered
Joined
·
5 Posts
Discussion Starter #1
Hello everyone! I just purchased a used 2008 Enclave CXL for $2500 on craigslist. It is in decent shape for the price. It has about 184k miles and the engine was replaced about 5 years ago. Not sure how many miles are on the new engine, but both the front and rear seals need replacing so likely a lot. I think the tranny has the waveplate issue even though it has probably been repaired before, as it shudders when driving with light to moderate throttle. There is a code I cannot seem to track down the cause of... 1175, Fuel trim cylinder balance bank 2. I have several live data captures that show the two O2 sensors with a difference most of the time. I have replaced coilpacks, moved around injectors, replaced the MAP sensor, cleaned the MAF sensor, replaced the bank 2 O2 sensor, replaced all spark plugs, and checked for vacuum leaks. There is a small vacuum leak still where the tube from bank 1 valve cover goes to the intake plunem. I tried using epoxy to seal it, but it looks like it may still have a slight leak. Just not sure that would cause the difference between the banks. Any help would be greatly appriciated. I really want to get this car restored to a reasonably dependable state.
 

·
Registered
Joined
·
6,454 Posts
the 2008s have a motor mount that is vacuum assisted. It has a hose running to it.


Im wondering if during the engine rebuilds-- the hose was left off-- or a motor mount with no vac assist was used.. leaving that hose unplugged.


On the 2008 Acadia, they did not use the vac assisted mount- and the intakes manifolds nipple, was simply capped off.
as the vehicle aged- that little cap covering the nipple- either fell off (after routine maintenance) or dry rotted- allowing a vacuum leak--- it caused rough running engine.
Wed point the owners to check- and sure enough the cap was gone or leaking. capping it off- and engine worked fine again.


Id check that hose....
 

·
Registered
Joined
·
5,904 Posts

·
Registered
Joined
·
5 Posts
Discussion Starter #5
Fantastic recommendation. Thank you! I had no idea about the vacuum assist on the mount, although I am not surprised. There seems to be a big push to reduce/eliminate vibrations in gas engines at this time. I wonder how much it has to do with electric cars and how quiet and smooth they feel when driving. I'll check that hose assembly and report back. Thanks again!!
 

·
Registered
Joined
·
5 Posts
Discussion Starter #6
Ok folks, I went ahead and just eliminated the vacuum motor mount system by removing its connection from the intake and attaching my vacuum gauge directly to the port. I should have done this sooner, but I am reading low vacuum, 14 to 15 at in Hg at idle. Interesting thing is, as soon as the AC pump kicks on, the vacuum jumps up to 16-17 in Hg. In addition, I see the difference in the trim banks disappear when the AC pump is engaged. As soon as the AC pump disengages, a 4% to 5% difference appears.

Questions...

Does the low vacuum automatically mean worn rings?

Could this be attributed to a bad VVT component? I am seeing unusually high misfires on cylinder 6.

Thanks!

P.S. I like the upgrade!
 
1 - 6 of 6 Posts
About this Discussion
5 Replies
3 Participants
Astro209
EnclaveForum.net: Buick Enclave Online Community
We’re a forum community dedicated to Buick Enclave SUV owners & enthusiasts. Come join the discussion about upgrades, towing capacity, reliability, and more!
Full Forum Listing
Top