Join Underhood Service On LinkedIn
Underhood Service’s LinkedIn Page Underhood Service’s LinkedIn Group Shop Owner’s LinkedIn Group
Honda Tech Tip: Oil Pressure Switch Fails Intermittently
The MIL comes on with one of these DTCS: P3400 (VPS Stuck Off Bank 1) or P3497 (VPS Stuck Off Bank 2). This may be the result of the front and/or rear rocker arm oil pressure switch intermittently failing.
Fuel Trim And AFR Sensors
Fuel trims are a difficult topic to cover in a matter of a few pages. But this summer, an old friend and former teaching partner arrived at our local car show with the check engine light illuminated on his 2004 Holden Monaro, which was imported from Australia and rebadged and sold in the U.S.
Check Out The August Issue Of Underhood Service Magazine
The digital version of the August issue of Underhood Service is available on-line. Access the easy-to-view digital version that features articles on Throttle By Wire, A/C Diagnostics, Fuel Injectors, Removing Bad A/C Smells, Rubicon Diagnostic Dilemma, Top Turbo Service Tips, Belt Inspection Checklist, Oxygen Sensor Replacement, a host of Tech Tips, and more!
Hayden Automotive Introduces Low-Profile Fan Clutch
Sitting at just 2.7 inches tall, the new low-profile fan clutch maintains the performance of the original fan clutch, but in a much smaller package. According to Hayden, this provides room for a thicker radiator when doing V8 restoration projects.
Belt Inspection Checklist
You might have only one chance to sell a customer a new serpentine belt. With belts lasting roughly 90,000 miles, proper inspection at the time of failure is critical not only for selling the belt, but also for ensuring add-on sales and better customer satisfaction. These are the steps you should be performing on every car or truck that enters your shop.
Preventive Maintenance Profits: Preferred Automotive, Jenkintown, PA
With the summer months heating up and cross-country road trips beginning, many people want to make sure their vehicles are prepped for the long haul. For the first-ever July edition of Maintenance Chronicles, we will focus on Preferred Automotive Specialists, a six-bay shop located in Jenkintown, PA. This shop boasts exceptionally high numbers in all
Nissan Versa Tech Tip: P0442, P0448, P0455 Or P0456
The MIL is “ON” with one or more of the following DTCs stored: P0442, P0448, P0455, P0456 and EVAP vent control valve is stuck open or will not seal when operated/closed.
Variable Valve Timing
One of the ways automakers squeeze more horsepower and torque from an engine is by adding variable valve timing (VVT) to the valvetrain. A conventional camshaft has fixed valve lift, duration and timing; so, the grind is always a compromise between fuel economy, performance and emissions. But with VVT, duration, valve overlap and timing can be changed on the go to optimize engine performance at different RPM, loads and operating conditions.
Chevrolet Tahoe: Tachometer Unresponsive To Engine Speed
Too many vehicles in the shop? Don’t have time to perform a thorough diagnosis on each one? Use this Real Fix to thin the herd by diagnosing your customer’s vehicle that has a similar symptom. Vehicle 2003 Chevrolet Tahoe, 5.3L Complaint The customer states the vehicle’s tachometer does not respond to the change in engine
Ford F-250: Check Engine Light, Code P0191
It’s OK to admit when you are stumped working on check engine light issues on F250s. You might not have figured out that the faulty powertrain control module caused fuel pressure to increase, which caused the engine to flood and the code P0191 to set. Don’t be afraid to seek help, and read this Real Fix to diagnose the vehicle.
Clicking Noise When Shifting Between Reverse And Drive Or On Hard Acceleration
Some customers may comment on a clicking-type noise coming from the front of the vehicle when shifting between reverse and drive or on a hard acceleration. Add a washer between the front wheel drive shaft and the bearing hub assembly using the procedure in this Tech Tip.
