So I went to the dealer to have a few codes read and plus Im having some bad MPG numbers right now.For one the P0430 code has been popping up for about 2 weeks which I already knew was one of the codes.The ABS light has been on for a few years.After about 2 unnecessary hours they come back and quote me this:

ABS Actuator $1755.00 + 130.00 Labor
Mass Airflow sensor $547.65
Quote-"Found mixture readings @ or below 94% Needs mass airflow sensor,
then recheck readings."

Here were the DTC results

TW Catalyst sys-B2 p0430
Data monitor NO DTC
Eng speed 700 rpm
mas a/f se-B1 1.37v
coolant temp 194 F
HO2S1 MNTR(B1) LEAN
A/F ALPHA-B1 94%
A/F ALPHA-B2 94%
VHCL SPEED SE 0 mph
BATTERY VOLT 13.9

Can anyone confirm that these readings are that far off to warrant needing a new MAF?I was hoping they had come back telling me to replace the B2 cat but they did not.What is a normal A/F alpha reading??

 

>$500 for a new MAF, are they serious?? I'm sure the abs actuator price is similarly absurd. Seems like you might have an O2 sensor problem but if you haven't put in a new MAF for the life of the car you could try that first, run you about $130 for an OEM green dot part.

 

Had that same code. It was intermittent. Got headers, used antifoulers on the secondaries (which is what that code is for) and I have not had that code or any other come up in about 2 years (25,000 miles).

 

yeah It was kind of funny.An ebay seller named bennettnissan has the green dot part for about 82 bucks.Im just hoping they didnt mis-diagnose this issue.The cat was not even acknowledged as being good or bad but they basically told me my A/F ratio was incorrect and I need to fix that first.

 

I thought about the antifouler trick but Im actually getting some bad mpg numbers right now so I dont want to mask an issue if there was a problem.
Im just concerned that there's really nothing wrong with my MAF and the catalytic converter really is plugged up.

 

Could always try cleaning the MAF with the proper spray. I'm sure the MAF on ebay is one without the resister. You needing the resister depends on if you have the 3.0 or 3.5 motor.

 

Buy a 3.0 maf for 100 dollars and move the little thermistor off your old one to the new one.

If the MAF is on the way out the voltage drops and makes the car lean out, it adds timing to compensate, among other things.

 

You may even want to buy a new thermistor to go with the new maf, they are very cheap and some guys have replaced them with good results

 

He has an I30, so he doesn't even have to worry about changing out the thermistor.

Just buy the green dot one that you found on ebay for $82.

PO430 definitely has nothing to do with the MAF, sounds like you need to replace/delete your pre cats. Are you Federal or Cali spec emissions?

 

If the car is running lean due to the MAF then it can throw an o2 code because that o2 is expecting a different afr

 

Yeah its an I30.Its cali emissions.Would the code remain if I gutted the bank 2 cat?Ive already ruled out the secondary O2 sensor because I replaced it and code came back. Also I saw a youtube video from a guy named scottykilmer who recommends trying laquer thinner in the tank and even removing and cleaning the cat Lol! What do you think?

 

^^ This guy is funny. He's always amped up.

You can probably do that to a main cat, but maxima precats are way too fine and made like crap (at least the 3.0s don't get killed by them haha).
They should just be removed.

But you could clean them since all the carbon is just on the very top. Dump some solvent in them upside down and let it eat the gunk up, then wash them off.
Or you could spend that time gutting them or headers.

 

Makes sense...Im gonna bite the bullet and buy the MAF.The only thing is that this OEM MAF has only about 89K miles on it and it has the green dot and Ive cleaned it twice(MAF cleaner) since its been installed so Im sure cleaning will do nothing.Ive also been playing with the car guage pro app for android phones so Im gonna compare the live data between the old and the new one and post all this info back up when I get it installed.

 

Thats the first thing I thought but he keeps it interesting!

 

What I did when I got the PO430/PO420 codes was, I bought a performance Y pipe from Warpspeed, and then I picked up a downpipe/precat from Walker. You see since your Cali spec, the Y pipe only deletes one precat, still leaving the one inside the downpipe.

After replacing these two things, you shouldn't see those codes come back. If you go the method of gutting the cats, then your gonna need either O2 sims, or anti foulers to keep the codes away.

 

I personally have never seen this happen.

And I've driven around with bad MAF's for a long time. My car has gone into limp mode because of a bad MAF, but that was it.

 

So I went ahead and purchased the MAF and sure enough the code returned after about 20 miles of driving.I was going to go ahead and purchase an Eastern cat since it was the cheapest so I said screw it and gutted it.When I looked through the honeycomb with a light there were really no clogs in it and there were no missing pieces but you can see that the center section was brown and had a resemblance of rust.Also the new MAF g/s readings were a little higher(about 3.1 new and old one 2.78 at idle) by a negligible amount and also those A/F alpha readings were almost the same between both MAFS so I think I just confirmed that whoever the tech was was full of ish really.I bought spark plug non-foulers from Autozone and was about to install but soon realized the 1/2" bit that I have is too large to fit my drill.Now I have no need for the cap-converter and wire mesh so if anyone needs it $15 shipped.

 

You guys who keep saying precats, do realize your main can throw this code? Happened to me. I have no pre-cats got P0430. Changed Rear O2 as it was dead. Code came back and the main cat efficieny readings are all over. I haven't changed it yet but my fronts read fine.

 

So whats measuring main cat efficiency and what are you using to diagnose it?
Did you move a secondary o2 behind the main cat?

 

TDotMax: You guys who keep saying precats, do realize your main can throw this code? Happened to me. I have no pre-cats got P0430. Changed Rear O2 as it was dead. Code came back and the main cat efficieny readings are all over. I haven't changed it yet but my fronts read fine.

PO430 is a precat code. I've had it, and replacing the front precat and deleting the rear took care of this code. No need for O2 sims or Anti Foulers. And I also still have the stock main cat.

 

To be honest, my mech was doing the readings on his scanner. I did not relocate any O2's. I never had this issue and had headers for 4 years and now I have p0430.