Question about 1990 GMC Sierra

1 Answer

1990 GMC Sierra 5.0 TBI doesn't pass emissions high hydrocarbons. Tested 3 times 1st test 2.02 second test measured at 2.04 and the third test measured at 2.14. I have passed all other test but can't

The obd1 codes are 22 Throttle position sensor voltage low ,33 MAP sensor voltage high,44 Oxygen sensor lean exhaust detected

Posted by on

  • Lupe Gavina
    Lupe Gavina Mar 28, 2014

    Forgot to add that the limit for hydrocarbons is 2.00 where I live

×

Ad

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • GMC Master
  • 3,679 Answers

Other than changing the identified parts ,which i imagine are expensive ,check all air intake pipe work as a split or worn hose can cause irregular air intake thus giving a false exhaust reading

Posted on Mar 28, 2014

Ad

4 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.
the service is completely free 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
hfmiles
  • 1165 Answers

SOURCE: 1989 f150 302 V8 fuel injected emissions problem.

Did you install new spark plugs? Definitely replace the O2 sensor.

Posted on Jan 12, 2011

Testimonial: "Thanks for the attention!"

  • 1 Answer

SOURCE: 1995 GMC Sierra

check you ideler sensor i had the same problem on

Posted on Oct 07, 2008

  • 71 Answers

SOURCE: 92 chevy truck 5.7 idle revs up and down high emissions

sounds like a vacuum leak check hoses and manifold

Posted on Mar 28, 2009

Add Your Answer

Uploading: 0%

my-video-file.mp4

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

×

Loading...
Loading...

Related Questions:

1 Answer

Did not pass emissions test for hydrocarbons


When was You're last Tune up?
Check the Spark Plugs to make sure the Gap is correct. HC is unburned fuel ,Check the Air filter and Replace as necessary,If coil over plugs Make sure to replace the Boots on the coils as they have a tendency to Bleed and wont show a trouble code.otherwise Change the Spark Plug Wires this should Clear You're Problem

Dec 31, 2014 | GMC Cars & Trucks

1 Answer

Hello...I have a '95 GMC K2500 Suburban with a 5.7L that failed a recent emissions test. I replaced the spark plugs, removed and cleaned the EGR...cap, rotor wires look OK...truck re-tested worst


Retarding the timing will cool the combustion which will lower the Hydrocarbon number,it will run bad but after a passed e test put the timing back to an advanced state which may help with the stumble.

Jul 22, 2017 | 1995 GMC Suburban

1 Answer

I have a high idle problem , with a 91gmc 1500 no codes but my scanner has a troubleshooter guide it says the seal gasket for the TBI is leaking vac I tested the TBI and it is working properly so I...


With the TBI, the AIC solenoid can get stuck and cause problems. It's on the passenger side of the TBI assembly and should have a four wire harness attached.

May 07, 2011 | 1991 GMC Sierra

1 Answer

My 1990 chevy astro van didn't pass smog. Paperwork says it failed the following; Ignition timing: 99 ATDC. Also, ASM Emission Test Results; 15mph HC (PPM) max is 122 measured 127, 25mph max is 102...


the smog test looks like the engine is miss firing, that could cause the timing to be out of whack also, try a old fashioned tune up, new spark plugs, wires, and filters also replace the PCV valve. any time you see the NO that high suspect a miss fire.

Feb 24, 2011 | Chevrolet Astro Cars & Trucks

2 Answers

Cannot pass emissions. Already changed plugs, air


Try cleaning the EGR valve or just replacing it and replace the PCV valve as well.

Nov 03, 2009 | 1990 GMC Sierra

1 Answer

1993 Grand Jeep Cherokee has fluctuating High emissions


everthing effects the reading. pedal position, rpm load engine temp. air temp. all that stuff you added was just a waste of time and money. What you should of done wa diagnosed it correctly so your not cheating an emission test. Since barley failed the first time I would of recommended a tunup if not done in 40,000 miles. I would have looked at the scanner data to see if the inputs were correct. Iwould have serviced the oil if its been awhile. If everything checked out i would of recommended a catalytic converter. But there are 3 test to determine if the cat is dead we do first. If your car was barley failing and you needed a tunup and the cat was still good the need for a tuneup could toast the cat within a couple weeks.

Aug 01, 2009 | 1993 Jeep Grand Cherokee

1 Answer

87 gmc suburban wont pass idle test


check vacume pressure at carb. diaphram had sim. prob. with 78 caprice

Jan 06, 2009 | 1987 GMC Suburban

Not finding what you are looking for?
Cars & Trucks Logo

121 people viewed this question

Ask a Question

Usually answered in minutes!

Top GMC Experts

yadayada
yadayada

Level 3 Expert

76848 Answers

Freddy

Level 3 Expert

1311 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22246 Answers

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

Answer questions

Manuals & User Guides

Loading...