98 QX4 has some issues! Dealer told me stuff, opinions please

[coledog188]

Ok, so my check engine light is on so I took it to our local Nissan dealer (Infiniti is over 2 hours away) to have it diagnosed.

Here is what they wrote on the order:

"Found codes P0171 fuel system lean, found right side catalyst plugged, recommend replacing.$1116.20Also found after market intake and mass air meter dirt, recommend replacing mass air is code stays after catalyst is replaced.$676.05Also found code P0440 EVAP small leak, found vent control valve bolts rusted and cracked canister, recommend replacing valve and canister.$487.15"

I'm planning on starting with the catalytic converter replacement and then reinstall the stock air box, which I kept.

Hopefully this will fix the first 2 issues correct?

However, I refuse to pay their exorbitant prices on parts...I found this: http://cgi.ebay.com/ebaymotors...ories and I think it should work as the QX4 is just a rebadged Pathy.

From Nissan Parts Direct I found the vapor canister for $145.19 and I think the valve is the PCV valve for $8. (Please correct me if I'm wrong)

Also, I no longer have the bolts for the stock air box (can't find them), does someone know where I can find these available?

Thanks for reading guys!
Modified by coledog188 at 5:27 PM 12/6/2009

[e2xx33]

Im pretty sure that cat will work. I have a 98Q as well. The bolts are 6mmx1.0mm- 30mm long with a large flat washer and lock washer, the nuts are the same thread size. Home Depot or Lowes should have it. I wish I could be more help.

[Pwnin O'Brien]

The item in the picture for the eBay auction is not your catalytic converter. The item pictured is the exhaust downpipe with the resonator. Many people think that is the catalytic converter since it resembles one in shape and size. Your actual catalytic converter is a round stubby thing which is bolted directly to the exhaust manifold.

Here is a picture of the catalytic converter for the 3.3L models...

[coledog188]

So I'd need something more like this: http://cgi.ebay.com/ebaymotors...ories ?

[fueler]

the EVAP leak code is a common one - just erase it i get that code every few years, it causes no problems and for the MAF being dirty - this is common with aftermarket intakes - all you have to do is clean it carefully as far as the cat.... that sux.... how the hell did it get plugged? I'd clean the MAF and reset the codes to see if it comes back, before replacing the cat. How does the QX4 run?

[coledog188]

There is a lot of hesitation going up hills and certain shifting situations. At first I thought it was the transmission having issues but I now understand how a clogged cat could do the same thing. It just never crossed my mind.

As the Nissan service writer said, "The car should get its guts back after the cat is replaced."

[Boston QX]

If you need to replace the Evap canister because the code is preventing you from getting an inspection, then there are ones on eBay for about $90 shipped. And it would be super easy to replace.

As for the MAF... the method I have used to clean them is get the purest isopropanol alcohol, put the MAF in a plastic freezer bag (don't touch the screen or filament), pour in the iso and swish it around. Then take it out and let it air dry.

[Boston QX]

Sounds like you need a Cat, too and I will tell the dealer is always going to be more expensive than an independent shop. I personally wouldn't bring an 11 yr old car to the dealer unless it was under warranty.

[GRNMACHINE]

U can always try a respected independent shop to replace your cat. Those bolts are going to be a bear to loosen from winter/salt etc. My Path has been garaged since purchased new but the winter is really rough on bolts etc. As posted, try cleaning MAF before replacing. They are really expensive for original Nissan.

I just bought some of those bolts from Nissan. If you want originals they are part no: 08146-6162H. I believe the list on them is $1.00 each. Some dealers are kind enuff to charge $2.50 each. Would rather have bought stainless at Menards/Home Depot/Lowes but only so much time (the Nissan bolts do rust). These bolts are used for the plastic "skid plate" and many other areas. Side note, if anyone needs these in bulk I believe there is a seller on ebay that sells boxes of them.