Idle Air Control Valve Problems and Solutions

Idle Air Control Valve Problems and Solutions

Tuesday morning, 7:30 AM. A ’98 Civic rolls into my bay with the customer white-knuckled and frustrated. “It keeps dying at every stoplight,” she says, her voice cracking. The poor girl’s been nursing this thing for weeks, restarting it in traffic like she’s playing Russian roulette with rush hour. One quick scan, a $47 part … Read more

Why Does My Car Idle Rough When AC Is On?

Why Does My Car Idle Rough When AC Is On?

  Last Tuesday, 3:47 PM—heat index 104°F—a sweating guy in a 2016 Honda Civic LX rolled into my shop looking like he’d seen a ghost. “It’s doing this every time I hit the AC,” he said, mimicking violent shaking. His knuckles were white on the steering wheel. I popped the hood and saw it immediately: … Read more

Vacuum Leak Diagnosis: Finding and Fixing Leaks

Vacuum Leak Diagnosis: Finding and Fixing Leaks

It was 3:47 PM on a sweltering Tuesday in July when Mrs. Henderson’s 2012 Toyota Camry rolled into my bay. “It’s making this weird hissing sound, and the idle keeps dropping so low I think it’s going to stall,” she said, wiping sweat from her brow. I’ve heard this story hundreds of times, and my … Read more

Engine Rough Idle: Causes and Solutions

Engine Rough Idle: Causes and Solutions

Quick Answer: A rough idle is often caused by vacuum leaks, a dirty or faulty idle air control valve (IAC), worn spark plugs, or clogged fuel injectors. Start diagnosis with an OBD2 scan for codes, check for vacuum leaks, and inspect plugs and the IAC. Many fixes are DIY-friendly and cost under $200. It was … Read more

Rattling Noise from Engine: What’s Wrong?

Rattling Noise from Engine: What's Wrong?

Quick Answer: An engine rattling noise is usually caused by a loose component (like a heat shield or accessory bracket), an exhaust rattle, low or incorrect engine oil, or internal issues such as timing chain rattle. The key is identifying when the noise happens—cold start, acceleration, idle, or deceleration—because each points to a different failure. … Read more

Grinding Noise When Starting Engine: The Complete Diagnosis and Repair Guide

Grinding Noise When Starting Engine: Diagnosis Guide

It was 6:47 AM on a freezing January morning when Sarah pulled into my bay with her 2015 Honda Accord. “It sounds like metal teeth chewing rocks,” she said, and honestly, that’s the best description I’ve ever heard for a failing starter motor grinding. I turned the key, and sure enough—GRRRRR-GRRRRR-GRRRRR—that unmistakable metal-on-metal shriek that … Read more

Ticking Noise from Engine: Common Causes

Ticking Noise from Engine: Common Causes

Quick Answer: That ticking sound? 8 times out of 10 it’s hydraulic lifters needing oil flow or fuel injectors doing their normal business. But if it’s loud, irregular, or changes with engine speed—especially after an oil change—check lifter noise first. Exhaust leaks and timing chain issues are serious but less common. Diagnose properly before spending money! … Read more

Radiator Issues: Signs Your Radiator Is Failing

Radiator Issues: Signs Your Radiator Is Failing

Quick Answer: Top Signs of Radiator Problems Engine overheating (temperature gauge in the red) Coolant leaks under the vehicle Discolored or sludgy coolant Clogged radiator fins blocking airflow Sweet smell from the engine bay It was a scorching July afternoon in Phoenix a couple years back—must’ve been 115 degrees out. This lady pulls into the … Read more

Engine Misfire Symptoms: What to Look For

Engine Misfire Symptoms: What to Look For

If you’ve ever felt your car shudder, lose power unexpectedly, or idle like it’s about to stall, you may be dealing with a classic—and potentially serious—automotive issue: an engine misfire. As an ASE-certified master technician with over 15 years of hands-on experience diagnosing everything from weekend project cars to daily commuters, I’ve seen misfires cause … Read more

How to Diagnose Engine Misfires: Complete Guide

How to Diagnose Engine Misfires: Complete Guide

Quick Answer: What’s the fastest way to diagnose an engine misfire? Start with a scan tool to pull codes (P0300–P030x). Then swap coils or plugs between cylinders and see if the misfire follows. 90% of random misfires are ignition-related; 8% are fuel; 2% are mechanical. It Started on a Freezing January Morning It was 7:42 … Read more