codes Archives - UnderhoodService
Misfire Codes P0300, P0301-P0312 and P0313+P0314

The only way to clear the code is to use a crankshaft position relearn with a scan tool.

Misfire Codes After A Spark Plug Replacement (Video)

After replacing spark plugs, you may get a handful of misfire codes. This video is sponsored by Autolite.

Diagnosing An Engine Misfire P0316 Code (Video)

Code P0316: Engine Misfire Detected on Startup (First 1000 Revolutions) could have many causes. Sponsored by Autolite.

What causes a P0420 code? (VIDEO)

If the front signals and the rear signals look identical, the catalyst is not doing its job. Sponsored by AP Emissions.

Traction And Stability Lights On With Code C0131

Technicians are advised to remove BPMV assembly and inspect the brake pressure sensor assembly.

ABS Fault Code 02757 Diagnosis Tip

Models: 2011-2014 Jetta, Jetta Sportwagen, Golf/GTI, Tiguan, Eos, 2012-2014 Beetle, Passat.

How Belts, Tensioners And Misfires Are Connected

Modern crankshaft position sensors measure more than the position of the crankshaft.

VIDEO: Solving An EVAP Leak Issue With A TSB

Andrew Markel discusses common EVAP system codes and how a TSB can help quickly solve this diagnostic dilemma. Sponsored by Nissan.

The Art of Diagnosing What the PCM Can’t See

The difficulties of diagnosing no-code drivability problems are best summed up by one of Yogi Berra’s famous quotes, “When you come to a fork in the road, take it.”

Piercing And Probing Wires With The Least Damage Possible

The Hippocratic Oath states a doctor shall “do no harm.” The technician’s oath is the same, but we “do no harm” to a vehicle we are trying to diagnose or repair.

EGR System Trouble Code Fixes

Testing EGR System Trouble Codes P047A and P047B on Volkswagens with the Tier2 BIN5 TDI 2.0L CBEA Diesel EGR System.

Accessory Belts, Tensioners And Misfires: A Balancing Act

Ever been amazed how complex some belt routing diagrams can be when all they are driving is an alternator, A/C compressor and maybe a power steering pump? The belt might be 8-feet long and loop around one or two idler pulleys.

belts tensioners misfires