Are you talking about taking the exhaust manifold with the pre-cat off. If so it took me about 30 minutes to get mine off. I had to take the alternator off then the pre-cat, really not much to it.
Jim
Jim
Is it really 12hrs to replace the VQ front precat?
Or did Mitchell's just have a labour hard on that day?
Had my first flicker of a P0430 (front side version of P0420) the other day, and yes, the precat seems to be a bit wobbly. Have parts, but had no idea everyone felt like quoting 12hrs to do.
AFAIK, there are 3 sets of bolts that need to come out, and the 3rd set may vary depending on reality. If you go by the FSM, it wants you do things like drain rad, remove the battery and drain the Power Steering fluid?! It also wants you to drop the suspension member (engine cradle that everything bolts to). Sounds like a brute force approach.
Seems to me, if the radiator/condensor/fans were removed you could come at it from the front, at least for the bank2 cat. Bolt Set 1, torch off the lower bolts on the exhaust tube. Set 2, the support bracket bolts for the precat itself. Set 3 are either the 6 holding ithe precat to the manifold, or the 6 holding the manifold to the block. Disconnect the O2 sensor harnesses, remove precat through the front. Remove O2 sensors...and reverse the process.
Anyone seen or done this? Exhaust bolts up my way normally require at least if a little acetylene...if not a lot, not something I'm setup for.
Had my first flicker of a P0430 (front side version of P0420) the other day, and yes, the precat seems to be a bit wobbly. Have parts, but had no idea everyone felt like quoting 12hrs to do.
AFAIK, there are 3 sets of bolts that need to come out, and the 3rd set may vary depending on reality. If you go by the FSM, it wants you do things like drain rad, remove the battery and drain the Power Steering fluid?! It also wants you to drop the suspension member (engine cradle that everything bolts to). Sounds like a brute force approach.
Seems to me, if the radiator/condensor/fans were removed you could come at it from the front, at least for the bank2 cat. Bolt Set 1, torch off the lower bolts on the exhaust tube. Set 2, the support bracket bolts for the precat itself. Set 3 are either the 6 holding ithe precat to the manifold, or the 6 holding the manifold to the block. Disconnect the O2 sensor harnesses, remove precat through the front. Remove O2 sensors...and reverse the process.
Anyone seen or done this? Exhaust bolts up my way normally require at least if a little acetylene...if not a lot, not something I'm setup for.
1 - 9 of 9 Posts
Apparently tolerances are a lot closer with the 3.5 VQ, and you are correct, even per the FSM the 2.5 only requires the alternator to be removed to get its precat off--unlike the 3.5 where batteries, rad hoses, power steering and subframes all get removed.. I'm going to price out the cost of going through the front...ie evacuate the AC, remove AC and radiator/fans...pretty sure that will get me the manifold bolts...at which point the big unknown are the 3 bracket bolts lower down.
Good grief, that is one heck of a deal to get that one off, I don't envy you at all there. Wishing you lots of luck and a easy repair.Apparently tolerances are a lot closer with the 3.5 VQ, and you are correct, even per the FSM the 2.5 only requires the alternator to be removed to get its precat off--unlike the 3.5 where batteries, rad hoses, power steering and subframes all get removed.. I'm going to price out the cost of going through the front...ie evacuate the AC, remove AC and radiator/fans...pretty sure that will get me the manifold bolts...at which point the big unknown are the 3 bracket bolts lower down.
Jim
Have decided not to proceed at this time. Code has not returned. I passed an emissions test which is good enough for my plate renewal later this year, even if it comes back on tomorrow. Going to take the wait and see approach...and keep the $1500 in parts & labour in my wallet. Call me Scr00ge...but better than Screwed.
I did the one on my wife's 2005 2.5 today and it took two hours total, and it didn't go smoothly. Granted, you've got more going on there, but I'd still think a novice mechanic should probably be able to achieve that in half the time you were quoted. I'd find a mechanically inclined buddy (who'll work for beer or favors), a good youtube video, and have at it once the weather warms up in the spring. That being said, if you go through all that trouble, it'd be a great opportunity to start replacing anything that'd ever given you a hint of trouble while it's already torn down.
Hey Dougmac, just curious how many miles/kms you got on your Altima? I’m at 107k on my 09
Hey, just coming up on 136km/85Kmi...code still has not returned. If the P0430 comes back, current plan is to find someone to borescope the inside of the precat for signs of deterioration via the AF O2 sensor ports before going too nuts on repairs...as I basically now have ~2 years before I need to pass emissions again (took the test after clearing the codes and doing the emissions run up, ie OBDII reported emissions system ready for test)Hey Dougmac, just curious how many miles/kms you got on your Altima? I’m at 107k on my 09
Its easier to gut the precats, install O2 extensions/defoulers, and weld in a high flow catOr did Mitchell's just have a labour hard on that day?
Had my first flicker of a P0430 (front side version of P0420) the other day, and yes, the precat seems to be a bit wobbly. Have parts, but had no idea everyone felt like quoting 12hrs to do.
AFAIK, there are 3 sets of bolts that need to come out, and the 3rd set may vary depending on reality. If you go by the FSM, it wants you do things like drain rad, remove the battery and drain the Power Steering fluid?! It also wants you to drop the suspension member (engine cradle that everything bolts to). Sounds like a brute force approach.
Seems to me, if the radiator/condensor/fans were removed you could come at it from the front, at least for the bank2 cat. Bolt Set 1, torch off the lower bolts on the exhaust tube. Set 2, the support bracket bolts for the precat itself. Set 3 are either the 6 holding ithe precat to the manifold, or the 6 holding the manifold to the block. Disconnect the O2 sensor harnesses, remove precat through the front. Remove O2 sensors...and reverse the process.
Anyone seen or done this? Exhaust bolts up my way normally require at least if a little acetylene...if not a lot, not something I'm setup for.
1 - 9 of 9 Posts
The Nissan Club
Welcome to Nissan Club, one of the largest Nissan forum communities. Discussion, reviews, maintenance and more.
Full Forum Listing
Recommended Communities
