Hi,

I purchased a 2007 with 60k miles at my local dealer on August 27th, and everything looked great including the carfax. Saturday night however I got check engine light, had autozone scan it for me and it was a P0420. I have less then 200 miles onto the car. Reading up on the problem seems to be common for 350z to have the cats fail. Also can I check if the car is still under the emissions warranty even though I'm the third owner?

Thanks
Frank

 

Do you have stock cats or aftermarket cats or a test pipe? If you have stock cats, then it might just be a failed O2 sensor. If aftermarket items, there is an adaptor for the O2 sensors that will prevent this.
http://bigdaddiesgarage.com/mini-cat-cel-fix.html

 

Just from taking a peak under the car, I believe they are stock.

 

From date put into "service", 8 year / 80k mile factory warranty on the cats. Otherwise, a reputable dealer should cover any problems for 30 days from purchase. This could also be a faulty 02 sensor but it's not unheard of for a catalytic converter to give it up at 60k, especially if the car has been run on cut-rate fuel.

Your 200 additional miles on the Z seems about right for a code having been cleared, then popping back up. You might insist the problem existed when you purchased the car and should be corrected at dealer's expense. Good luck with that!

 

i know when i bought my corvette, the dealership had a 10 day 500 mile full return policy if i decided against the car. you would think your dealership would take car of it... i would go there and go straight to the sales manager

 

As others have said, your first option is to take it back to the dealer you bought the car from. If it's a generic used car dealer, they'll likely point to the "no-warranty" sticker that was posted on the car and you likely signed after the sale. But if it was a Nissan dealer, they should start the warranty process to see if the repair is covered. Don't be surprised (particularly if you didn't buy the Z from them) if a Nissan dealer makes you pay for the diagnostic fee. It's usually an hour of shop time and is refundable if they find the CEL was caused by the emissions warranty.

 

I'm sorry, I said "local" dealer. I call the ford dealer my "local" dealer, I own two ford vehicles, this is my first nissan. But I took the car in this morning, they just took in the service area and the service manager said "We'll take care of you". Also the dealer has a 72-hour buy back program or under 300 miles. Genuinely like the car though so I would rather keep it.

I have only filled up the car twice, once for $20 and there other to fill it up all the way for $40 both at a shell using premium gas.

Thanks,
Frank

 

[edit] I'm glad the dealership you bought it from were stand-up about it. That's pretty rare.

The only way to fix this is to replace the cat (I've had both of mine replaced under warranty). FWIW, I take my car to Younker Nissan in Renton for warranty repairs. The service center crew there is great to work with. All other repairs I do in my own garage.

 

I've been told it's almost ALWAYS a failed cat on the 07-09 and cut rate fuel has nothing to do with it. I've run mine on Chevron premium since I bought it new. One cat quit at 15K and the other died at 22K. The HR cats are garbage.

 

All Nissan cats are garbage. Most common cat failures... 4 cylinder Altimas (pre-'13), 4.0L trucks (all years), Titans (pre-'09), 350Z's (all years). Rarely see 6 cylinder FWD cats go bad or older V6 trucks.

 

Update,

My dealer is ordering a part from the cat manufacturer. It isn't a stock cat, I asked them if they checked the cat and all and they yes everything is fine, they just need a device that will trick the o2 sensor?

Will let you know what the cats are, i forgot to ask when I got off the phone.

 

Regards, zakmartin / franknstn:

Nissan voids any emissions warranties if contaminated fuel is used. Nissan will also void warranty if non-OEM or unapproved modifications are made to either the intake or exhaust. However, earlier this year "The FTC says this practice violates the Magnuson-Moss Warranty Act and must stop. Companies can still require that you submit to arbitration before filing suit, but after that you're free to take them to court."

With secondary quality fuel here's what can happen: Cut-rate gas frequently contains sediment and water, it's typically referred to as cheap gas for a reason. These stations are routinely fueled from a tanker carrying the last fuel drawn from reserves at bulk suppliers. Offered by the distributor at a lower cost and marketed to the consumer at reduced rates. As with bulk reserves, these unwanted contaminants concentrate at the bottom of that station's underground tank. Drawing fuel from a low tank will have an even greater proportion of these substances. Water in the fuel reduces fuel efficiency and depending on the level of contamination exhaust gasses containing higher percentages of hydro-carbon and carbon dioxide can enter the exhaust system. Catalytic converters begun to function at 400 to 600 degrees. Normal operating temps can reach 1,200 to 1,600 degrees. With the introduction of pollutants, temps can reach 2,000 degrees. Coatings on the honeycomb then begin to melt and settle into the ceramic substrate. Should these temps continue for more than just a few minutes an additional increase in temperature may be the consequence, the honeycomb itself may melt potentially causing a partial or complete blockage of the exhaust.

A too rich mixture is the most frequent cause of cat failure, if your cats rattled this may be what happened. Extended stop 'n go / low throttle demand is another contributor to early cat failure. Mention of an unusual odor when "blowing out" the exhaust is frequent, a result of "lighting up" the catalytics and burning off sulfide exhaust by-products.

Cliff's Notes: Run your Z like it was meant to be run every now and then. Tune following modifications and fill with top-tier gas, it's good sense.

 

So they are ordering you some spark plug extenders with a holes drilled in them to move your 02 sensors out of the direct path of the exhaust flow. This will probably keep your check engine light off. Also pretty much make the sensors not sense much.

 

Here's the part, its a stillen high flow cat.

https://www.stillen.com/stillen-niss....html?___SID=U

Tech showed me this,

 

I'd tell them to replace the cat with a new OEM cat and a new OEM cat only or you want to back out of the deal. They're trying to go cheap on you and it's just going to cause more problems down the road.

And what? They're going to put in one hi-flow cat and leave the other one alone? That's going to cause all sorts of issues. Don't forget, any cars in Seattle made before 2009 still need to get an emissions test done every two years. You're going to be screwed if you take it in and don't pass.

 

Get a second opinion (like from a Nissan dealership). Personally, I think these guys are full of ****.

 

I apologize for not making it clear. The previous owner has both Stillen HFC's. The tech checked both of the cats and are working fine, the check engine light is due to the HFC's and that he said the previous owner probably just cleared it everytime it showed up. So he's getting the extensions for the o2 sensors, I will talk to the service manager to get him to put it on writing that if this fails emissions they will make it right for it to pass emissions.

He did clear the CEL since monday and it hasn't come back since then.

 

Okay... good example of why you need to list all mods before you post your problem in the maintenance and repair forums.

 

The OTHER thing to watch is ( once the " extenders" are installed ) is your fuel economy.
The O2's might not toss a code , but they MIGHT give false info to the ECU.. net result over rich.. and bad gas milage....

Mike

 

the main cause of bad gas mileage is your right foot