Question about 2003 Chevrolet Impala

1 Answer

2003 impala. Hard starts and fumes smell.

2003 chevy impala 3.8 engine. Hard starts 50% of times and smells of fumes when this happens. I have a code of P0420. Had the Cat converter changed 2 years ago. The 02 sensor was NOT changed then. Car now has 145K on it. Could this be my 02 sensor? Thx

Posted by on

  • Paul Marks May 12, 2015

    Sounds Like to me the PVC value is Plugged change it done problem solved

×

Ad

1 Answer

  • Level 2:

    An expert who has achieved level 2 by getting 100 points

    Hot-Shot:

    An expert who has answered 20 questions.

    Corporal:

    An expert that hasĀ over 10 points.

    Mayor:

    An expert whose answer gotĀ voted for 2 times.

  • Expert
  • 54 Answers

This is what i found for you

The catalytic converter has an oxygen sensor in front and behind it. When the vehicle is warm and running in closed loop mode, the upstream oxygen sensorwaveform reading should fluctuate. The downstream O2 sensor2003 impala. Hard starts and fumes smell. - icon1.png reading should be fairly steady. Typically the P0420 code triggers the Check Engine Light if the readings of the two sensors are similar. This is indicative of (among other things) a converter that is not working as efficiently as it should be (according to specs). It is part of the vehicle emissions system.

Most likely, the aftermarket cat they installed is a high flow cat. This commonly causes issues with throwing that code on our cars. You can either have an OE cat installed, or just have the code deleted from the PCM by someone that has a tuner.
Good Luck

Posted on Jan 10, 2013

Ad

6 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
  • 2 Answers

SOURCE: 2003 Chevy Impala Service Traction Sytem show on Dash

I can't answer the question about the gas fumes, but I had the same problem last year with the "Service Traction Sysytem" message and the Trac and ABS lights coming on in my Impala. Mine turned out to be because of a bad wheel bearing, that was causing the ABS and traction system not to work. I'm not sure if you've experienced this, but another thing that would happen with mine was that I would go to brake and have a hard time depressing the brake pedal, almost like it was pushing back. That is the point when the Trac and ABS lights came on.

Posted on Jan 22, 2009

emissionwiz
  • 76118 Answers

SOURCE: 1997 LINCOLN TOWN CAR - CHECK ENGINE LIGHT( code P430)

I think you will find the aftermarket Cat Conv. is the source of your problem, but without hooking up to the factory test equipment at my disposal at my Ford dealer this at best and educated guess based on 20 years of emission related work, I am a Ford certified master electronics technician

Posted on Jan 30, 2009

  • 1071 Answers

SOURCE: I am getting a P0430 and a P0420 code on my 05

there are two more sensors and i would use chrysler sensors

Posted on Jul 21, 2009

CMV9
  • 594 Answers

SOURCE: Pulled code p0420 on 99 chevy astro, 2wd, v6

from what i am finding the code means o2 sensors. they recommend replacing them and if this does not work than replacing the cat converter

The catalytic converter has an oxygen sensor in front and behind it. When the vehicle is warm and running in closed loop mode, the upstream oxygen sensor waveform reading should fluctuate. The downstream O2 sensor reading should be fairly steady. Typically the P0420 code triggers the Check Engine Light if the readings of the two sensors are similar. This is indicative of (among other things) a converter that is not working as efficiently as it should be (according to specs). It is part of the vehicle emissions system.

causes

A code P0420 may mean that one or more of the following has happened:

  • Leaded fuel was used where unleaded was called for
  • An oxygen sensor is not reading (functioning) properly
  • The engine coolant temperature sensor is not working properly
  • Damaged or leaking exhaust manifold / catalytic converter / exhaust pipe
  • Retarded spark timing
  • The oxygen sensors in front and behind the converter are reporting too similar of readings
possible soloutions

Some suggested steps for troubleshooting a P0420 code include:
  • Check for exhaust leaks at the manifold, pipes, catalytic converter. Repair as required.
  • Use a scope to diagnose the oxygen sensor operation (Tip: The oxygen sensor in front of the catalytic converter normally has a fluctuating waveform. The waveform of the sensor behind the converter should be more steady).
  • Inspect the downstream heated oxygen sensor (HO2), replace if necessary
  • Replace the catalytic converter
One thing to note is that many vehicle manufacturers offer a longer warranty on emissions-related parts. So if you have a newer car but it's out of it's bumper-to-bumper warranty, there still may be warranty on this type of problem. Many manufacturers give a five year, unlimited mileage warranty on these items. It's worth checking into.


thank you for choosing fixya and please do not forget to comment and rate on your experience.

Posted on Aug 20, 2009

  • 56 Answers

SOURCE: 2003 Chevy Impala periodically won't start

Try under the dash, attached to colum is a switch that the rod goes into from your ignition key switch, that may need to be adjusted tword your steering wheel just a touch, they go out of alignmnet from time to time

Posted on Sep 15, 2009

Add Your Answer

Uploading: 0%

my-video-file.mp4

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

×

Loading...
Loading...

Related Questions:

1 Answer

2004 chevy impala problems


Have it towed to a shop & repaired

A list of ten things you know nothing about
or how to test won't help you

Jul 14, 2014 | 2004 Chevrolet Impala

1 Answer

Engine light came on smell gas fumes see no leakes its a 2003 dodge grandcaravan


My 2004 Mazda 6 had a similar problem. It smelled like gas inside the car and had code # P0456. I found that the PCV line was pinched. The line was not an Original Equipment. I replaced the line and the PCV valve. So far so good...

Apr 13, 2014 | Dodge Caravan Cars & Trucks

1 Answer

2003 chevy impala cuts out and shifts hard sometimes. Check engine light is not coming on. Could this be some kind of sensor going out?


Okay a few things to check first, with car off, turn key to on position but do not start, does the check engine light light up, failed bulb? run codes anyway, most chain auto stores will do for free, check transmission fluid it it dark, burnt smelling? how many miles ? when was transmission serviced if ever? did you check spark plugs are they worn out? fuel filter changed if over 50k miles could be blockage and resettles when sitting. lots of things could case this issue, i would check light and codes first.

Jun 09, 2012 | 2003 Chevrolet Impala

2 Answers

Turns over well but is slow to fire off sometime. Can smell gas fumes inside the car as well as the outside. No black smoke from ehaust and no fuel leaks.


if you smell gas YOU DO have a fuel leak.... make sure your gas cap is good and or tight, also might want to look at your fuel pressure regulator.. the fuel system is pretty simple... let me know!

Jan 22, 2011 | 2003 Nissan Altima

1 Answer

I have a 2003 chevy impala. The impala spudders and dies. Also, there is a strong gas smell. What could be my problem


It definitely sounds like the fuel pressure valve located on the end of fuel rail on engine.Its about $50

Jan 16, 2011 | 2003 Chevrolet Impala

2 Answers

The smell i'm having is not the raw gas smell , it smells exhaust fumes getting in the car. i checked for exhaust leaks buut had none


if inded the smell of exhaust is getting into your car i would suggest not driving it until it is properly checked by a licensed meachanic. it could be entering through your heater/AC blower and in return be fatal if left untouched for a period of time

Jan 11, 2011 | 2005 Chevrolet Impala

2 Answers

My chevy impala smells like the radiator liquid is burning and the check engine light came i put coolant in there and the check engine light went off but it came back on. it seems to be leaking coolant but...


Check the front passenger side carpet and make sure it is dry. If it is wet, the heater core up under the dash is leaking, which is why you smell it in the cab.

Sep 22, 2010 | 2003 Chevrolet Impala

2 Answers

2005 impala smells like fuel at start up and while driving, gas tank not leaking. smell fumes worist @ morning starts even when heater off and vents shut


its your fuel pressure regulator. pain in the rear to change. its the small brass looking thing next to the throttle with a vacuum line going to it . the part cost me 50$ and i paid a guy $ 75 to put it in. worth every penny. looks easy to change yourself, but not as easy as it looks.

Mar 03, 2010 | 2005 Chevrolet Impala

1 Answer

Engine light on--exhaust smell in car--just replaced engine


the ac is a gas leakage problem and can be fixed by an accredited ac specialist shop
the exhaust gas smell could be the flex pipe at the exhaust manifold or a exhaust pipe gasket that has failed ( come loose after the engine replacement)
as for the engine lights , it con=mes on from reports from the engine and the transmission so have the fault codes read to find which sensor is reporting a fault
could be that same sensor that reports on the exhaust problem
hard to start is an electronic reporting fault and that will be in the codes as well

Apr 22, 2017 | 2003 Saab 9-3

1 Answer

2003 Chevy Impala Service Traction Sytem show on Dash


I can't answer the question about the gas fumes, but I had the same problem last year with the "Service Traction Sysytem" message and the Trac and ABS lights coming on in my Impala. Mine turned out to be because of a bad wheel bearing, that was causing the ABS and traction system not to work. I'm not sure if you've experienced this, but another thing that would happen with mine was that I would go to brake and have a hard time depressing the brake pedal, almost like it was pushing back. That is the point when the Trac and ABS lights came on.

Jan 01, 2009 | 2005 Chevrolet Impala

Not finding what you are looking for?
2003 Chevrolet Impala Logo

125 people viewed this question

Ask a Question

Usually answered in minutes!

Top Chevrolet Experts

yadayada
yadayada

Level 3 Expert

76109 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22156 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

8270 Answers

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

Answer questions

Manuals & User Guides

Loading...