Question about 2001 Pontiac Bonneville
Troubleshooting p0446 and p1404
P1404 is a common problem on GM cars and trucks. You might have some luck cleaning it (carbon deposits). Use carb/choke cleaner but be careful where you spray it. Once you clean it, you will need to erase the error code. You can try one of the Auto Parts stores that will 'lend' you a scan tool. Another trick is before you clear the code(s) and after you have cleaned the EGR, unplug the connector to the EGR valve. Clear the codes, turn the ignition switch OFF immediately after you clear the codes. Reconnect the EGR connector, remove the Scan Tool and start it up. By turning the key off immediately, it resets the pintle position of the EGR valve. Otherwise it 'remembers' the old position and you will get the error code back. Worth a try before you invest in a new EGR valve...
Posted on Nov 20, 2009
STOP TOPPING off the tank while you gas up.
Few ounce of fuel in the EVAP vapor can stock a perfect engine from running.
Disconnect the charcoal canister line and let the car vent OUTDOOR over night.
you other problems
vacuum leaks on intake manifold,
the air tube between the air filter.
intake manifold vacuum hose.
clean throttle plate with Berryman carburator cleaner
SEE sample picture HERE
Also remove carbon built up behind the EGR valve and the EGR passage tube.
Vacuum leak WILL offset the intended 14.7 to 1 air fuel ratio.
More un-metered air (leaks) will lean out the fuel mixture.
Use small amount of Berryman carb clearer at potential air leak area will help you identify trouble spot.
At idle,just spray and listen for the RPM surge.
The in-rush of carb clearer will increase the RPM on the motor.
Record the problem spot(s) and address it later.
EGR carbon built up require 2+ hours to clean from start to finish.
You will need a new EGR base gasket before your start.
Locate and remove the EGR valve after the vehicle is cool down.
Carefully record the connector and vacuum line (for older vehicle) location by drawing an easily to follow diagram.
Remove the EGR valve.
Inspect the location of the carbon built-up inside the valve and the EGR passage tube.
SOAK these areas with WD-40 spary.
You will need a small screwdriver,cloth hanger and lot of newspaper and time to get this cleaning done right.
RE-SOAK the carbon and let it sit for over-night will also help.
One the last round,pass a shop vacuum of the EGR valve and the passage pipe.
Install the new EGR gasket and connectors.
Allow the vehicle to warm up outdoor to burn up any remaining WD-40.
Take it for a test drive.
Please rate my answer if it's useful to you.
Posted on Dec 19, 2009
The po446 is the evaporative emission system.Check all the lines going back to the fuel tank.This is for a restriction in the vent system.Usually a vent valve not working.It is under the vehicle by the gas tank connected to the canister.The 1404 is for the EGR valve.If the vehicle is running good it is stuck closed.If it is running rough it is stuck open.Usually stuck closed.It is under the hood on the engine by the rear of the back velve cover.Good luck.
Posted on Nov 20, 2009
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.
Posted on Jan 02, 2017
Tips for a great answer:
Jan 25, 2017 | Pontiac Cars & Trucks
Jul 17, 2015 | 2007 Buick Rendezvous
Aug 17, 2014 | 1999 Isuzu Rodeo
P0431 Warm up catalytic converter, bank 2 - efficiency below threshold
Possible causes: Catalytic converter, wiring, HO2S 2
Usually caused by worn out catalytic converter, but always check fuel pressure regulator for proper operation before replacing a converter.
P0446 Evaporative emission (EVAP) system, vent control -circuit malfunction
Possible causes: Wiring, EVAP canister purge valve, ECM
May be caused by a loose or disconnected wire to the vent valve or possibly a bad valve solenoid
If you would like part locations, troubleshooting or replacement procedures, please let me know.
Dec 01, 2010 | 2004 Kia Sedona
Jan 30, 2010 | Chevrolet Cobalt Cars & Trucks
Nov 01, 2009 | 2002 Buick Park Avenue
1,578 people viewed this question
Usually answered in minutes!
Step 2: Please assign your manual to a product: