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Obd code po300 and code po420 truck is missing

Obd code po300

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Mulitiple cylinder miss fire,May be the coil boots and plugs,will fix your problem,and,or fuel injection cleaner with a couple of bottles of HEET,a water dryer to put in the fuel tank.

Posted on Nov 13, 2009

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Posted on Jan 02, 2017

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Can catalytic converter cause a PO65O code

Pesky PO420 Codes - Eastern Catalytic
One of the most annoying is the persistent PO420 diagnostic code (Catalyst System ... not only shows its teeth when the catalytic converter is on the blink, but can also be ... Most, if not all, catalytic converter failures are caused by a problem or ...

P0420 Error Code: Catalyst System Efficiency Below ...
Repair information for the OBD-II trouble code P0420 - Catalyst System Efficiency ... If they have failed, it is likely due to something else that caused it to fail. ... the catalytic converter is broken or failed, it may be restricting the exhaust which will ...

explaining trouble codes po420 - po421 - Discount Catalytic ...

Jan 16, 2016 | Cars & Trucks

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P0300 misfire code

Ignition Module
Vacuum Leaks
Valve issues
Timing Issues
Blocked Converter
Then about 10 more possibles

Being 1996 was the first year for OBD 2 Systems
You have at least some scan tool data IF you have a professional
scan tool

You have all YOU will ever need on the internet IF you know how to
ask the right questions

You can spend a lifetime looking at,printing & studying anything
about any subject

I suggest you first study OBD 2 Systems
Then the individual Components
Then get to how to test for cylinder misfires

To find out about codes

TYPE: OBD & the code ---- that easy

OBD PO300 (never need help again)

Aug 13, 2014 | Cars & Trucks

1 Answer

Sensor codes
This is what the codes mean.

Your carburetor and fuel system is acting up (or you lost the fuel cap!)
You need a carburetor and engine service. This is not a user friendly problem!

Mar 09, 2014 | 1998 GMC Safari

1 Answer

I have 2 codes PO 300 and PO 420

po300 is a random misfire code(could be egr passages blocked under upper pleinum;plug wires;plugs or coils.PO420 is catalatic converter below threshold(converter has to be replaced)

Jan 02, 2014 | 2001 Pontiac Grand Am SE

1 Answer

PO016, PO300, PO420, PO442 codes

your engine is misfiring according to your codes ...4 codes 4 problems
P0300 - Random Cylinder Misfire DetectedP0301 - Cylinder 1 Misfire DetectedP0302 - P0312 Cylinder X Misfire DetectedP0325 - Knock Sensor 1 Circuit (Bank 1)Just showing a few

Oct 23, 2013 | 2003 GMC Envoy

1 Answer

Why is my car missing cylinders 2,4,6 $ random

What vehicle do you have,motor etc?
I would say you got bad ignition coils
or a reason for the PO300 codes
Stop using it
The codes or mil lamp is there to tell
you to get it fixed, as it wants to protect
the exhaust converter & the air we breathe
You Google the codes for the answer
OBD Code PO301 etc
Forget the 300 multiple misfire code,don't need that
You need professional help & professional test equip

Aug 09, 2013 | Cars & Trucks

2 Answers

What is an code po300 and po420 and what do i need to do i have an 2002 nissan altima

The p0300 code is a random missfire code sometimes caused by bad spark plugs and wires, if you have not done a tune up, it's time for one. now, the p0420 code is for catalyst efficiency below threshold, basically, your catalytic converter is bad and may need to be replaced. Sometimes repairing the random missfire can eventually clear the p0420 code. your car is not burning fuel properly, therefore the catalytic converter is getting dirty. Also, if you notice blue smoke coming out the tail pipe, then that's the cause for a failing catalytic converter as oil is getting to the combustion chamber and being burned off through the exhaust.

Mar 09, 2010 | 2002 Nissan Altima

1 Answer

I have a diagnostic trouble codes p1768,po300,and a po420. what does this mean?

I have tow of the three requested codes. po300 is misfire detected at multiple cylinders. See po301-306 represent the cylinder # misfire. So 301 is cylinder #1 misfire.

po420 is Catalytic Converter Efficiency Failure

Oct 08, 2009 | 1996 Plymouth Voyager

2 Answers

TROUBLE CODES= P0301 & P0305 ?

po420 codes what does it mean

May 27, 2008 | 2000 Lincoln LS

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