Question about 1995 Buick LeSabre

1 Answer

Failed e test-nox

EGR pintle not opening - new valve.

Posted by on

1 Answer

  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 1 Answer

Check the egr system

Posted on Sep 04, 2010

Add Your Answer

Uploading: 0%

my-video-file.mp4

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

×

Loading...
Loading...

Related Questions:

1 Answer

My 1989 Mercedes 260E has no EGR valve and CA emission test failed NOX. What's next?


You engine came with EGR, here is a picture of it, make sure it is functional.808daddd-23be-456e-979e-50a2188da73b.jpg

Apr 10, 2013 | Cars & Trucks

1 Answer

Trouble code P1406 Failed EGR value, Open or short circuit condition Also code P0301 misfire cylinder 1 Next steps? Information for replacing EGR value? 1997 Bonneville SE 105K


P1406 Code - EGR Valve Pintle Position Circuit
The PCM monitors the EGR valve pintle position input to ensure that the valve responds properly to commands from the PCM and to detect a malfunction if the pintle position sensor and control circuits are open or shorted. If the PCM detects a pintle position signal voltage outside the normal range of the pintle position sensor, or a signal voltage that is not within a tolerance considered acceptable for proper EGR system operation, the PCM will set DTC P1406.

CONDITIONS FOR SETTING THE DTC

Ignition 1 voltage is greater than 10 volts.
EGR Feedback is less than 0.14 volt at any time.

OR

EGR Feedback is 0.4 volt greater or less than the EGR Closed Valve Pintle Position when the Desired EGR Position is commanded to 0%.

OR

Actual EGR Position is 20% greater or less than the Desired EGR Position.
Any of the above conditions are present for longer than 20 seconds.

ACTION TAKEN WHEN THE DTC SETS

The PCM will illuminate the Malfunction Indicator Lamp (MIL) during the second consecutive trip in which the diagnostic test has been run and failed.
The PCM will store conditions which were present when the DTC set as Freeze Frame and Fail Records data.

CONDITIONS FOR CLEARING THE MIL/DTC

The PCM will turn the MIL OFF during the third consecutive trip in which the diagnostic has been run and passed.
The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
The DTC can be cleared by using the scan tool Clear Info function or by disconnecting the PCM battery feed.

DIAGNOSTIC AIDS
Check for the following conditions:

Open EGR ignition filter circuit.

An open in the EGR ignition filter circuit will cause EGR Position Error to vary erratically while the EGR valve is operating. With the ignition ON, a test light should illuminate when connected between ground and the EGR ignition filter circuit at the PCM connector. If not, locate and repair the open in the EGR ignition filter circuit.

Excessive deposits on EGR valve pintle or seat.

Remove the EGR valve and check for deposits that may interfere with the EGR valve pintle extending completely or cause the pintle to stick.

Poor connection or damaged harness. Inspect the wiring harness for damage. If the harness appears to be OK, observe the Actual EGR position display on the scan tool while moving connectors and wiring harnesses related to the EGR valve. A change in the display will indicate the location of the malfunction.

Reviewing the Fail Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set

TEST DESCRIPTION
Number(s) below refer to the step number(s) on the Diagnostic Table:

Verifies that the malfunction is present.

The PCM contains a recirculation diode which filters the EGR ignition feed for the EGR valve. The recirculation diode is connected to the ignition filter (EGR ignition feed) circuit. If the ignition filter circuit is open, Actual EGR position may be erratic when compared to Desired EGR position. An open in the EGR ignition filter circuit will cause DTC P1406 to be set after an extended period of time.
If DTC P1406 will only set under certain conditions, the malfunction may be intermittent; refer to DTC P1406 Diagnostic Aids. If an intermittent wiring problem is not present, check for a poor connection at the PCM or the EGR valve. If the connections are OK and DTC P1406 continues to set, replace the EGR valve.

This vehicle is equipped with a PCM which utilizes an Electrically Erasable Programmable Read Only Memory (EEPROM). When the PCM is being replaced, the new PCM must be programmed.


------------------------------------------------------------------------------------------------------------------------------
P0301 Code - Cylinder #1 Misfire Detected
A P0301 code means that the the car's computer has detected that one of the engine's cylinders is not firing properly. In this case it's cylinder #1.

Symptoms may include:
the engine may be harder to start
the engine may stumble / stumble, and/or hesitate
other symptoms may also be present

Causes: A code P0301 may mean that one or more of the following has happened:
Faulty spark plug or wire
Faulty coil (pack)
Faulty oxygen sensor(s)
Faulty fuel injector
Burned exhaust valve
Faulty catalytic converter(s)
Running out of fuel
Poor compression
Defective computer

Possible Solutions:
If there are no symptoms, the simplest thing to do is to reset the code and see if it comes back.

If there are symptoms such as the engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in the car, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I've also heard in other cases the problems were faulty fuel injectors.


Check it and keep us updated.

May 03, 2011 | 1997 Pontiac Bonneville

2 Answers

My 1997 gmc sonoma truck,it has a V6,4.3 liter V-Tec failed the MIL/Check Engine Light Test due to a Warning Lamp Failure. Due to a OBD Fault Code:P1406 manufacturer specific code


This code indicates a problem with the EGR valve's pintle position. The EGR Valve's pintle could just be stuck in which case the problem could be fixed by cleaning the EGR valve.

If the EGR valve is electronically controlled or cleaning the valve does not fix the problem, you will most likely have to replace the EGR Valve. i hope this helps

Feb 08, 2011 | GMC Sonoma Cars & Trucks

1 Answer

What is the meaning of a failing test with NOx(ppm)


Oxides Of Nitrogen (NOX)

Above 2500 degree engine combustion temperature
nitrogen bonds to oxygen to form NOX

The EGR Valve is supposed to allow a certain
amount of exhaust gases into incoming air to
control high combustion temperature and control
NOX

Bad Egr Valve
Engine operating too hot
Cat too cool at inspection station
Fuel mixture issues
PCV issues
O2 Sensor issues
Injector issues
Ignition issues

Jan 30, 2011 | Toyota Previa Cars & Trucks

1 Answer

I have a 2005 Dodge Dakota V8 4x4 My check engine light turned on. I took the truck to Autozone to have them hook up the machine and see what the problem was. It said I have a bad EGR Valve. I havent...


It can affect mileage, but it might not be the valve. EGR systems tends to get clogged by gunk. Take the valve off and see how dirty things are. If the system is clogged up, take apart as much as you can to clean it up. You can test the valve for operation with a good scanner (autozone doesn't do this--they just tell you the code). Here are instructions from autozone.com:

Linear EGR Valve Diagnosis
The linear EGR valve diagnosis procedure varies depending on the vehicle make and model year. Always follow the recommended procedure in the vehicle manufacturer's service manual. The scan tester may be used to diagnosis a linear EGR valve. The engine should be at normal operating temperature prior to EGR valve diagnosis. Since the linear EGR valve has an EVP sensor, the actual pintle position may be checked on the scan tester. The pintle position should not exceed 3% at idle speed. The scan tester may be operated to command a specific pintle position, such as 75%, and this commanded position should be achieved within two seconds. With the engine idling, select various pintle positions and check the actual pintle position. The pintle position should always be within 10% of the commanded position. When the linear EGR valve does not operate properly:
  • Check the fuse in the 12 V supply wire to the EGR valve.
  • Check for open circuits, grounds, and shorts in the wires connected from the EGR valve winding to the PCM.
  • Use a digital voltmeter to check for 5 v on the reference wire to the evp sensor.
  • Check for excessive resistance in the EVP sensor ground wire.
  • Leave the wiring harness connected to the valve, and remove the valve. Connect a digital voltmeter from the pintle position wire at the EGR valve to ground, and manually push the pintle upward. The voltmeter reading should change from approximately 1 V to 4.5 V.
436f9a1.jpg Linear EGR valve circuit. Courtesy of Chevrolet Motor Division-GMC.
If the EGR valve did not operate properly on the scan tester and tests 1 through 5 are satisfactory, replace the valve.

Here is what your valve looks like:
If you have more questions, please let me know.
a65cb7d.jpg

Oct 13, 2010 | 2005 Dodge Dakota

1 Answer

High nox fail smog test any remedies? 99


NOX is created when the internal combustion temperature gets to high.The egr system uses burnt exhaust gases to line to cylinder walls.The purpose of this is decrease internal combustion temperature therefore reducing the amount of NOX created.Would look to a possible egr malfunction usually they will trigger the check engine light but not always.The 4.3L has been known to have issues with carbon buil up in the egr and the egr pintle not open and closing properly.

Jun 07, 2010 | 1999 Chevrolet Astro

1 Answer

Failed emissions....high nox


Sticking egr will raise everything except nox. Bad o2 bad cat hard to give an accurate diagnosis with out checking it

Oct 12, 2009 | 1994 Lexus LS 400

2 Answers

Failed e-test in 91 ranger


change the oil just before the test and get the Cat as hot as u can.

Jun 01, 2009 | 1991 Ford Ranger Supercab

2 Answers

Emissions failing with high NOx


Change the lambda/oxygen sensor in the exhaust.

May 21, 2009 | 1994 Mitsubishi Galant

Not finding what you are looking for?
1995 Buick LeSabre Logo

Related Topics:

97 people viewed this question

Ask a Question

Usually answered in minutes!

Top Buick Experts

yadayada
yadayada

Level 3 Expert

61037 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

21949 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

6812 Answers

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

Answer questions

Manuals & User Guides

Loading...