Ole Red - 1999 Toyota Tacoma Xtra Cab 2.7L 3RZ-FE 4x4 SR5 All Manual Build

What he said ^^^^^^

 

Yep, weird smell lately.

Cracked header is distinctive smell. The additional smell most recently should be the catalytic converter I am assuming...

 

Maybe. I've heard a P0420 code and a propane smell could be a heap of different things. O2 Codes, Not enough/bad Diff Oil, not enough/bad tranny oil/ not enough/bad transfer case oil/ bad 02 sensors/ cat converter, and even MAF sensor. I haven't found one answer everyone agrees with. Let me know what you decide on doing, cause I got the same exact problem buddy.

 

Just replacing that leaking manifold with the OEM mini header should help out with all those issues and you might just get lucky and it will solve the code. It will put more heat and pressure on the cat, once that is sealed up again,, if you go that route.

 

Header and catalytic converter ordered... pictures to come.

 

Header and cat will be nice upgrades, and hopefully fixes your error code issue. That said, if you still get an occasional propane-ish smell (especially at higher rpm/lower gears) I wouldn't fret, the trans breather is right next to the shifter and sometimes a little smell gets into the cab... especially on older trucks. I noticed you mention a trans fluid change in post #4, and in case you haven't done so recently, I'd change of the oil in the t-case and both diffs as well. It's pretty easy and cheap. I've found that the tranny and front diff need a change only every other time I do the t-case and rear diff. This is after years of changing all four at the same time with the rear diff and t-case oil coming out looking very well used and the tranny and front diff oil coming out practically looking new.

 

Hey clickws. I'm kind of in the same boat as you with the P0420 code.

I purchased my 99 Tacoma XtraCab 2.7L (200k miles) on Craigslist about two weeks ago, and the P0420 showed up two days later. I'm guessing it has been there for a while, but the guy who sold it to me likely cleared the codes just before my pre-sale test drive. Smart for him. Naive for me.

I'm no mechanic, and today is my first day on Tacoma World. What follows is my "non-technical, guy-who-sits-in-an-office-all-day, Tacoma owner" assessment of my P0420....so feel free to correct/educate me if anyone disagrees:

I tested my Cat with an infrared thermometer. From what I understand, while driving a vehicle that is sufficiently warmed up, a healthy catalytic converter's OUTLET should read much hotter than its INLET. For example, on a healthy Cat you might see the temperature readings of exhaust going IN at 400 degrees and come out the other side at 550 degrees (these are EXAMPLE numbers only!!!) So I go for a 30 minute drive, then pull over and take some temp readings. On mine, the temp readings on the outlet side are consistently the same or lower than the inlet....which is one indication there is a problem with the cat.

My next Cat check included hooking my real time scanner up and observing the O2 Bank1 Sensor1 and Bank1 Sensor2 voltage output while driving. Here's my scanner:

for Android Phones ONLY - Wireless Bluetooth Diagnostic OBD2 Scanner Car Code Reader and Scan Tool for All 1996 & Newer Vehicles ELM327 Compatible OBDII

http://www.amazon.com/gp/product/B005NLQAHS?psc=1&redirect=true&ref_=oh_aui_detailpage_o02_s00

It's my understanding that the inlet O2 sensor should fluctuate quite a bit (between 0 and 1) as its checking fuel trim, whereas the outlet sensor should be more steady. In my case, they both fluctuated a lot...almost in sync.

After doing my own DIY tests, I decided to take the vehicle in. I dropped it off at my mechanic this afternoon and simply told him my check engine light was on. Nothing more. An hour later, he called and said my cat needs to be replaced and suggested I consider doing the O2 sensors as well. I told them to do the Cat only, as the sensors are a piece of cake to replace. I'd do the Cat replacement myself if it wasn't welded in. Again, I sit in an office all day and don't know how to weld. I won't be doing many mods, and I won't ever climb rocks....but I love this freaking truck.

I'll get my Taco back in the morning and post an update.

 

Weo

Welcome to TW! And great job searching threads to find your answer instead of posting a new one!

 

Pickles!

Thanks for posting. I certainly follow your logic. You honestly did more testing than I did. Just from reading, there are common issues that pop up and more often than not, the Toyota only has issues where technically it should. All catalytic converters bite the dust someday.

Others may correct me if I am wrong, but the catalytic converter should have flanges that can bolt on or off. You could have bought and bolted a new one on. But as I said before, your time is worth something. So if it makes more sense for someone else you trust to change it out, then no qualms... Its personal preference. If it were welding, then absolutely I would let a professional handle it.

I like the code scanner you posted. One of the better I've seen so far. (limited research)

If you get the catalytic converter changed out. You may not need O2 sensors replaced. It may be good to do it while you're working on the truck but may not be necessary if they are working like they should. Obviously are since they gave you a check engine light.

I liked the approach to playing dumb when you took it in. smart move. Keeps people honest and unbiased.

Looking forward to the update. I am waiting on a delivery...

 

What kind of mechanical locker you have? recommend?

What kind of tires?

 

I'm a little late but on the manifold I heard the 01-04 create some more power or go ahead with an lce. On mods, I'd do wheels, tires, and if you see a lot of night hwy with deer like I do, get a plate bumper.

 

Another thing I've needed to cover or replace is the front drivers seat. I currently have the driver's "bench" seat. No one has ridden there since highschool... Any suggestions where to get a good single. I feel as though I have exhausted craigslist and local junk yard resources. I wouldn't be opposed to replacing them both.

 

Just got my truck back after having a new Catalytic converter installed. The P420 is gone, but I'll obviously need to complete a few drive cycles to be sure it doesn't come back on. I'm pretty confident I should be okay though. I plugged my scanner in and observed the voltage of both O2 Sensors as I drove back to work. Bank 1 Sensor 1 oscillated nicely, while Bank 1 Sensor 2 was nice and steady around 0.7 volts. Clearly the new Cat is converting as I was getting much different readings before the install.

I'm looking forward to hearing how your header install goes, Click. I don't see any cracks in mine yet, but I plan to put enough miles on it that it'll happen eventually.

 

Thanks again pickle.

That is a promising result. That's what I hope will happen when I get my new catalytic converter. Obviously the new header will hopefully help from pulling cold air in that may have contributed to the check engine.

Hoping this thing comes in tomorrow. Maybe first of next week.

 

Does anyone have a good link to pictures or a video that could help with new header and exhaust install on the 2.7L 3RZ-FE?

 

Well, here ya go. Bit the bullet and got a better deal by getting the full set up. Any tips for install would be helpful. THX.

 

Just picking back up over on the build. Stay "tuned".... lame pun

 

Lol, just a heads up, all is not lost if you round the torx stud head off you can do the double nut trick to pull them out and put them back on.

 

Is that that ProFlow Exhaust from LCE as well? Also, was the Cat from LCE too? I'm hoping to do this to my truck after I re-gear. I think that my current Cat is not factory though because it is welded on the exit side of it and has a bunch of hanger mounts on it. What did you pay for just the Cat? Thanks for the info

 

Yup,,this. Broken Stud grabbers available also at all the big names usually. I have a old Jacobs chuck I modified that I use with a pipe wrench. Matter of fact, I need to get that back, it's loaned out.

Next time I do this for someone, the motor will be to operating temp,,then spray and yank(carefully) all that stuff loose. Kevlar/welding gauntlets required and a extra extension maybe.

I did slather everything with super slippery silver stuff when it went back together.