Question about Cars & Trucks
I replace O2 sensors .
Save hours of searching online or wasting money on unnecessary repairs by talking to a 6YA Expert who can help you resolve this 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.
Here's a link to this great service
Posted on Jan 02, 2017
SOURCE: fails idle emissions test hc
****** ignition timing....this will lower HC but raise other values during test.
Do you have room to increase other values?
After test return timing to the most advanced position without spark knock under load for best MPG.
Posted on Aug 11, 2009
SOURCE: failed smog check
How well does the vehicle run?
Assuming that the engine did pass the EGR function test on the emission test results, and the MIL (Malfunction Indicator Light) or check engine light is not on when the engine is running, and if you are not sure when the last time it was that the engine had a complete tune-up, with distributor cap, ignition rotor, spark plugs, spark plug wires, air and fuel filters, then a complete tune-up would certainly help, and if the engine oil and oil filter have not been changed in a while, then they should also be changed before an emission test because long used engine oil traps carbon and it will show up as higher CO on the emission test because the emission analyzer will be able detect the higher CO from the engine oil through the PCV valve.
However, it would seem from those HC readings that there is a vacuum leak, and carefully inspect all of the vacuum lines for any cracks or damage, (especially the vacuum line to the fuel pressure regulator) because cracks in the vacuum lines seem to like to hide underneath the lines.
The emission label under the hood should have the vacuum line routing diagram printed on it, and the vacuum lines should all be checked to be certain that they are all connected correctly.
Here is the firing order diagram for that vehicle to help assist you tune-up the vehicle.
Posted on Jul 10, 2010
check for any vacuum leaks, run some injector and combustion cleaner through it, check the pcv valve and the egr valve, and fresh oil, can't think of anything else
Posted on Nov 17, 2010
Testimonial: "Logical friendly advice...Thanks!!"
SOURCE: 1993 S10 Chevrolet Blazer DID
what about the air filter is it clean ,silly question i know but you would be surprissed ,does this vehicle have one O2 sensor or two one after the cat as well or is it too old for two O2 sensors ,i know most europeon market vehicles didnt have cats till 1992 and most didnt have two sensors till around 2000 ,also check the two white or two black wires on sensor for 12v these are the heater feed wires for the sensors
Posted on Jan 03, 2011
Tips for a great answer:
Mar 09, 2016 | 1998 Nissan Altima
Mar 13, 2014 | 1988 Chevrolet K2500
Mar 05, 2013 | Chevrolet C1500 Cars & Trucks
Feb 08, 2013 | Dodge Cars & Trucks
Dec 06, 2012 | Cars & Trucks
Aug 25, 2012 | Cars & Trucks
Jan 12, 2012 | Chevrolet Blazer Cars & Trucks
Apr 05, 2011 | 1997 Honda Civic
Jan 17, 2010 | 1998 Dodge Neon
Mar 07, 2009 | 1991 Honda Accord
113 people viewed this question
Usually answered in minutes!
Step 2: Please assign your manual to a product: