Question about 1996 Toyota Avalon

1 Answer

1996 toyota avalon failed emissions test high hydrocarbons and they keep rising 3rd test thus far failing at 15 mph portion of test the more i fix the worse it gets it is barely out of range

Before first test replaced catalytic convertor changed oil and cleaned plugs not of that much wear fairly new 11000 miles or so and car barely passed emissions but it did pass however was failed due to self test system not completed cycled pulled code was egr insufficient flow tested all that i could within reason my first time on an egr system problem boy what a tempermental system toyota has indeed cleaned complete egr valve intake manifold plenum throttle body etc. to new condition removed all carbon deposit/soot replaced air filter and put in 91 octane gas 2nd time failed at 15 mph test slightly high hydrocarbons mil activated paid 90.00 hooked it to a dyno supposedly? bad egr modulator oem replacement it did in fact have a tiny whole in diaphragm ran self drive test no mil from this point on failed again at 15 mph test cycle even slightly higher hydrocarbons than previously tested nitrogen oxides have declined to 0000 carbon monoxides steady o2 increased a little dont know if that means anything on the o2 all tests on 25 and idle passed and it passed the first time only **** mil messed it up for a fail result to begin with very frustrating am replacing oxygen sensors although there is no code prevalent nor pending ran some garaunteed to pass cleaner threw a tank of gas and going for oem plugs but not wires at this time i am running out of money i am also going to fill up with 87 octane rather than 91 this time i dont understand the more i do the worse it gets it is so close and car runs like a champ runs fast and jumps high a real trooper my dad 1 owner highway miles of 217000 total any advise encouragement direction experience GREATLY APPRECIATED thanks to all for your replies

Posted by on

Ad

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Top Expert:

    An expert who has finished #1 on the weekly Top 10 Fixya Experts Leaderboard.

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

  • Toyota Master
  • 3,698 Answers

Have you tried Engine decarbonizing type foam to remove the excess carbon for the engine?

Posted on May 13, 2014

Ad

2 Suggested Answers

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
New users get to try the service completely Free afterwhich it costs $6 per call and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
Goodluck!

Posted on Jan 02, 2017

Ad
  • 202 Answers

SOURCE: 1995 Toyota Camry - Code 71 - failed emissions tests

replace the EGR switching valve and have the machanic clear the engine check light. I think it should help



Posted on Mar 31, 2009

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

Virginia emissions test failed - 15 MPH HC and CO; 25 MPH HC


get your injectors cleaned. change the air filter .change your plugs. put a fuel cleaner in your fuel tank.

Dec 01, 2013 | 1998 Volvo S70

1 Answer

1994 toyota tercel failed emission test no(ppm)max 15 mph 516 mine 785 at 25 mph max 568 mine513


I suggest you use Google to find & study any number of sites
that explains exhaust gases & how to correct them

Aug 28, 2013 | Cars & Trucks

2 Answers

1995 Honda Civc failed Emmisions test


Emission test by codes reader? or smog? Any codes?

May 22, 2017 | 1998 Honda Civic

2 Answers

1986 CHEVY CK20 FAILED EMISSION TEST HIGH HYDROCARBONS


mccartlidge. are you serious?? high HC is the result of a headgasket problem??? do everyone a favor and dont give advice when you clearly dont know a damned thing about emissions. as far as solutions to your high HC output, someone else mentioned the possibility of a worn out cat along with carb problems and or a simple air fuel adjustment. this car if i remember correctly has a feedback carb which means it has an oxygen sensor and a mixture control solenoid on the car to fine tune the air fuel mixture. it is not uncommon to have a oxygen sensor not functioning at all or out of normal calibrated range. easy test for oxygen sensor(single wire oxygen sensor ) is to hook up a voltmeter at 0 to 1 volt range(positive lead to oxygen sensor wire, negative lead to any good ground source) and watch the voltage. a perfectly working system the signal should look like a wave constantly rising and falling from .9v-.1v. test at 2500 rpm as well as at idle on a hot engine.if the oxygen sensor doesnt rise and fall, add fuel(spray small amount of carb spray) into carb while at idle or high rpm and the oxyen sensor should go full rich(approx .8-1v) that is point 8(.8v) not eight volts. you will usually see a reading of .9v . if the oxygen sensor doesnt put out a rich reading than its no good. on the other end you can remove a vacuum line(brake booster hose, half way removed as to not stall the engine) the oxygen sensor should go lean which means around .1 volts. if the oxygen sensor does not respond correctly replace it. beyond that, the engine first and foremost has to run on all cylinders to run clean and efficient. if it has a missfire or dead hole that will cause high HC along with high CO as unburnt fuel is going out the tail pipe. i could go on and on about possibilities but figured i would give you a couple basics to go on. Good luck.

Aug 12, 2012 | Chevrolet Chevy Cars & Trucks

2 Answers

My 95 Lincoln towncar failed smog due to high nox at 15 mph


Your EGR is plug or is non operational,When the EGR is not plug and is in operational its job is to cool the combustion chamber thus lowering Nox.

Mar 29, 2012 | Cars & Trucks

1 Answer

1989 Toyota 22re fails California Emissions Test. Rebuilt the engine 20K or so miles ago. Has passed most tests with just a little bit of timing adjustments. At 15 MPH, (1670 RPM) HC measures 153...


HC is hydrocarbons or unburnt fuel.(raw fuel ).NO no such gas measurement.did you mean CO this is carbon monoxide or incomplete combustion.(all the fuel is not being burnt).if you mean NOX this is nitrates of oxide and is related to a heat problem.(motor running hot,bad catalytic converter).its probably getting too much fuel and not burning it all,possibly tune-up problem,carburetor(if it has one),bad fuel injection system(dirty injectors),computer(if it has one)may be getting a wrong signal.these are in reference of high HC and CO.for high NOX cooling system not keeping motor cool enough,cooling fan problem(weather clutch fan or electrically controlled cooling fan),poor cooling system circulation,bad catalytic converter.not a running lean problem as the other gases indicate rich problem.the converter may not be able to convert the emission gases to H2O and CO2 out the tailpipe.

Apr 24, 2011 | 1989 Toyota Pickup SR5

1 Answer

My c220 failed smog because of high hydrocarbons at 25 mph


hc's are unburned fuel- I would change my sparkplugs and resmog it if that is the only gas that was high

May 20, 2009 | 1994 Mercedes-Benz C-Class

1 Answer

1991 Nissan Pickup Fail Emission for Hydrocarbons


i know it sounds silly but the garunteed to pass stuff at the auto stores work.

Mar 05, 2009 | 1991 Nissan Pickup

1 Answer

Emissions


Sounds like it's not getting enough oxygen to burn all the hydrocarbons and carbon. Change out the oxygen sensor. Hope that helps. Is the air filter dirty? It might even improve things enough if you just change that.

Jul 17, 2008 | 1992 Buick LeSabre

2 Answers

Mot failure on emissions


make sure to smell the oil and see if it is contaminated with fuel
if it is then do an oil change and try to re test

May 27, 2008 | 1996 Toyota RAV4

Not finding what you are looking for?
1996 Toyota Avalon Logo

220 people viewed this question

Ask a Question

Usually answered in minutes!

Top Toyota Experts

yadayada
yadayada

Level 3 Expert

76649 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22219 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

8522 Answers

Are you a Toyota Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...