I live in California and I just bought a 94 Yota 2 wheel drive 22RE motor. It failed the emissions aspect of the smog test and I don't know why. Everything else passed. The mechanic recommended that I get a tune up; new wires, spark plugs, oil change, and an engine flush. However, this all has been done except for the engine flush. It's only been about 1500 miles since the tune up. The motor has about 200,000 miles. Here is where it failed;

25 MPH HC (PPM) max-60 ave-22 meas-72

Therefore, I barely failed by 12. I don't know of anything that is causing the truck to fail. Any tips or suggestions?

 

Don't live in California.

 

look like you have some unburn fuel

 

yes I do have unburned fuel but how do I resolve it since I already did a tune up?

 

try see foam? mabey clean out your fuel system?

 

Well isn't the evap portion of the smog test part of the fuel test because I passed the evap test. The mechanic told me the evap is to check for any fuel leaks in the lines. Im not sure if cleaning out the fuel will help emissions.

 

Maybe its running rich? Might try mixing a little E85 gas in the tank just for the test. Is the air filter clean?

 

Yes air filter is really clean. I got that K&N.

 

Will running synthetic oil help?

There are tons of posts titled smog something on here. I don't read them myself but maybe helpful.

 

How does the Cat look and do you know how old it is? My 86 had very high HC at the last smog check and even though it was low enough to pass I took the cat off and put a new one on. The old one was so deteriorated inside I cant believe it actually did anything.

 

lol thats funny

 

or try running higher octain gas, even tho its like 4,00 a gallon

 

It isn't running VERY rich - especially for those miles. It's those very tough CA smog specs that got you. I would make sure your injectors are as clean as you can get them by running through a bottle of a cleaner that includes polyether amine, the only really effective injector cleaning chemical. I think the only two products left that have it are Red Line's SI-1 Complete Fuel System Cleaner, which has the most PEA, and next best is CRC's "Guaranteed to Pass: Emissions Test Formula". That has a decent amount of PEA. After running that through the tank, your emissions probably will improve a bit. Techron, Gumout Regane and BG 44K no longer have PEA.

Another thing that can cause rich running is an older O2 sensor that is partly fouled. They tend to read lean when they age, causing the computer to add too much fuel. OR, if the connector or wiring is a bit corroded, that also fools the computer into thinking it's running leaner than it really is. So checking that connector and cleaning it up if it looks corroded is a good thing to do. If the O2 sensor has over 90k miles, you may want to replace it. The direct-fit Denso is by far the best way to go. Suggest getting the part number from sparkplugs dot com and searching for denso and the part number on amazon - they've been cheapest there lately.

Finally, how old is the cat? If it's old, you probably could solve your emissions troubles with a new one. You should be able to find a CARB certified Magnaflow for not much over $200. You can find the part number here: http://www.car-sound.com/02product/02directfitCARB.asp

Here's a pretty good page on the new CA cat laws: http://www.car-sound.com/04basics/04california.asp

Good luck.

EDIT: If it has been running rich there is probably some fuel dissolved in the oil, which can add to a rich problem. Suggest changing the oil to something a little on the heavy side right before retesting, like a 10W-40. Valvoline MaxLife is very good.

EDIT2: You might check that your cold start injector is not leaking. If you can remove it while keeping the fuel line attached, do that and jump +B & FP in the gray plastic check connector on the side of the black fuse/relay block on passenger inner fender. Then turn ignition on (but don't start it). That will run the fuel pump and pressurize the fuel lines, so you can check the injector for leakage. There is a small chance one of the other injectors might be leaking, too. If you really want to be sure about the injectors, send them to witchhunter.com They do a great job cleaning and flow testing, and provide new o-rings and a quick turnaround for $19/injector.

Another thing to check for is an exhaust leak that might allow more air to be sucked into the exhaust stream, throwing off the measurements of the O2 sensor.

 

get the msd6 spark box and the ignition coil they supposed to burn off all the gas and give you better milage

 

Thanks everyone for your suggestions. And living in Cali will be forever. I think imma clean my injectors, check all sensors, and try that seafoam as well as an oil change then drive it for awhile before the test. More suggestions if anyone has more. Also if it doesn't pass I found somone that will do it for $90

 

I had the same problem in AZ with my 95 4runner 3vze with 219k. I fail by a couple of points. I changed the oil (which you have already done), sprayed some water up the exhaust to clean it out (with the engine off of course, and its the stock exhaust), put 91 octane in it and fuel injector cleaner (with an empty tank) and changed the timing to 5 degrees (was at 10). ran it for 2 days took it back and passed. only other thing I can think of is the o2 sensor. Good luck, hope you pass

 

Thoughts on replacing the O2 sensor: https://www.yotatech.com/forums/f116...sensor-193571/

Going from "Gross Polluter" to 0 PPM HC: http://www.toyotanation.com/forum/sh...d.php?t=327671

FSM chapter on testing the O2 sensor: http://personal.utulsa.edu/~nathan-b...42oxygense.pdf

 

I take it there is no CEL on, so another thing to check is the PCV is the right size orifice. One more option is checking your temperature gauge is reading your truck warm otherwise if its reading cold, like from bad thermostat or fan clutch, then it will also run rich, thinking it cold, in open loop.

 

my vote is on the cat converter too.

last year, i couldnt pass even though i did all the tricks i did before. had a full tuneup. nothing. 91 gas. nothing.

then i remember it's been years... dang cat.

cost over $200 and i immediately drove to the TEST ONLY station. passed by 1 point... hee hee... now i have 2 years...

couple more things:

1. get an oil change. my 4runner is a now weekend toy, so the oil sits... and sits... well a few years ago, first time i ever FAILED, it's been like 8 months since last oil change. but mileage was still less than the usual 3000 that i started on. well one number was like 130 and that's what failed. after the oil change, it drop to around 90 and PASS! the testing guy asked my what i did. i told him. oil change.

2. drive around for a good 30 minutes to get the cat at the peak temp. not in the freeway. but city roads.

 

I am new to Commifornia too, I failed test, replaced cat, adjusted timing to 5 btdc, passed.