10 Signs A Fuel Injector Needs To Be Replaced
In the past 30 years, the fuel injector has moved from the intake manifold to the combustion chamber. During this evolution, injectors have become more precise in dispensing fuel. If this precision is thrown off by restrictions, electrical problems or fuel problems, it can cause driveability issues. These are the top 10 signs fuel injectors need service or replacement.
Snap Test: MAF Sensor Diagnostics
You’d think a service light would be the first indicator of a mass air flow (MAF) sensor problem, but there are times a problem develops with the MAF and no service light comes on. Scott “Gonzo” Weaver explains how poor idle, loss of performance, sluggish performance and even stalling are all associated with a failing MAF sensor.
Diagnosing Variable Valve Timing
Fully variable valve timing can be achieved only by using computer-operated solenoids to precisely control the intake and exhaust valve opening and closing events. Although the various combinations of valve timing events are theoretically infinite on an electronically controlled system, their applications are limited due to issues of cost and, in some cases, reliability.
Lessons From A Day Being Out Of My ‘Comfort Zone’
Being under the dash or hood of the modern car is my comfort zone, but it doesn’t hurt to get out of my comfort zone from time to time. You can take those average days in your own little comfort zone for granted and forget there is more to what makes the world go around besides the next car you’re working on. Sometimes, it might take a little nudge from an outside source to get you to realize it.
Nissan Diagnostics: Check Engine Light And Misfire Issues
The late-model Nissans have proven to be quite reliable when it comes to serial-type problems that would get them to your bay with check engine lamp issues. Nissan has done a good job of addressing some of the problems we’ve looked at in the past. But that doesn’t mean you won’t be seeing Nissans looking for attention, and that spells service opportunities for you.
OBD II Misfire And Diagnosis
When diagnosing misfires, it’s important to use tools that allow you to go beyond a simple code reader that displays a P03XX. Even an OEM-level scan tool can’t tell you what the firing voltage is or what the ignition pattern looks like. Nor can it tell you if the serial data is accurate or correct. For that kind of information you need a DVOM or a graphing multimeter/oscilloscope that can look at sensor voltages directly and display primary and secondary ignition patterns.
Diagnostic Dilemma: 1999 Dodge Dakota Intermittent Stall Complaints
Diagnosing intermittent stalling complaints is a challenging experience for any diagnostic technician because any number of electrical and mechanical failures can cause an engine to intermittently stall. Most of us immediately narrow this laundry list of potential failures down to the most common few, which include components like the crankshaft position sensor and electric fuel pump.
Cold Weather Diagnostics: Modules Go Down With The Temperature
The subject vehicles were 2002-2006 Ford trucks – the first was a 2002 Ford F-150 with a 5.4 liter, second was a 2006 Lincoln Navigator with a 4.6 liter and finally a 2004 Ford F-250 with a 5.4 liter engine. All of the customer complaints with these vehicles were the same: “The vehicle will not crank/start when cold.”
GMC Sierra: No-Crank/No-Start Condition
Customer Concern: The battery was jump-started with the key on, which resulted in a no-crank, no-start condition. Theft deterrent module (TDM) DTC B3060 is present. The module will perform the
GM Power Steering Pump Replacement Tips
An analysis of returned power steering (PS) pumps that had been replaced for noise, no power assist, no or low pressure and leaking conditions has indicated a high number of “No Trouble Found” results. When attempting to repair a power steering concern, the steering system analyzer should be used to assist the technician in a successful diagnosis.
Failing Pilot Bearing, Bushing on Manual Transmissions
Most rear wheel drive, and some front wheel drive, vehicles with manual transmissions use a pilot bearing/bushing. The pilot bearing/bushing
Diagnosing EGR And Secondary Air Systems
The perfect internal combustion vehicle would be able to put the exact amount of fuel and air into the combustion chamber. If the perfect combustion event happened, you would get nothing more than water and carbon dioxide. We are not there yet. In the mean time, we have exhaust gas recirculation systems (EGR), secondary air injection and catalytic converters.