CALL NOW - (618) 233-6119TEXT US NOW

Monday - 8:30 am - 5:00 pm
Tuesday - 8:30 am - 5:00 pm
Wednesday - 8:30 am - 5:00 pm
Thursday - 8:30 am - 5:00 pm
Fri Sun- Closed



321 Centreville Ave.
Belleville, IL 62220


"We Believe an Educated Client is a Satisfied Customer"Home » FAQs

▶ What is my proper tire pressure?

The tire pressure rating printed on the sidewall of the tire (usually 44 psi max.) is NOT the rating for your vehicle. This is just the maximum safety limit for the tire, depending on the vehicle on which it is installed. One tire can fit many types and sizes of vehicles. The manufacturer has placed a decal sticker (usually found in the driver’s door or jamb) that states the recommended tire pressures for that tire and vehicle combination when cold. In this case, cold means that the vehicle has been parked for at least 8 hours. As a vehicle is driven, the friction of the tires against the road can cause the tire pressures to increase by 2-3 pounds very quickly. Also, most cheap tire-pressure gauges do not read accurately, so you need to have yours compared to a professional gauge so that you know what reading on your gauge gives the proper pressure for your tire. For example, your tires are filled to 31 pounds of pressure, using a professional gauge. Check the pressure right away with your own gauge. If it reads just 28 pounds, you then know that you don’t want to exceed that number on your gauge to maintain proper tire pressure.

▶ Why should I consider using Nitrogen in my tires?

Tires have become expensive and a new Federal law requires all vehicle to be equipped with a Tire Pressure Monitoring System (TPMS), because a low tire is a dangerous tire. Tire pressures are sensitive to temperature. For every 10 degrees the temperature changes the tire pressures change 1 pound. The aircraft and racing industry have been using nitrogen for nearly 50 years. But, with the cost of tires and human life it is now recommended that nitrogen be used in automotive tires. While some manufactures are now including it with there new cars. Nitrogen is not sensitive to temperatures, does not leak out as fast as air and can increase tire life by as much as 35%!

▶ What is a good oil change interval? And why?

This has become a very controversial subject. We have always recommended 3,500 miles. And now manufactures are running algorithms to determine when they think it’s best to change the engine oil. If you read the fine print it tells you that it can’t determine the level of dirt that may have accumulated or the environment you may be traveling in, which would drastically affect the oil change interval.  But the bottom-line is that nearly everyone shops for price, which has not changed much over the last 30 years compared to other services. So, the weak link in today’s oil changes is not the oil but the filter. We still recommend not exceeding 4,000 miles in an oil change.

▶ My check engine light is on but it runs just fine, should I be concerned?

Yes. The “Check Engine” or “Service Engine Soon” lamp is KING!  When this light is on, it is letting you know that an emissions failure has occurred. This can be as simple as a loose gas cap or as complex as a rational test failure. A rational test is when the computer can’t figure out what is exactly wrong but nothing adds up. Remember, there is only one light bulb and as many as 2,000 codes. Also, when the light is on the computer may be making adjustments to keep the vehicle running well, which may be costing you in gas mileage and future repairs. Plus if anything else were to go wrong, you would be able to be warned, because the light was already on. For further information, read our Noteworthy article on “Repair Myths.”

▶ Why won’t my ignition key turn?

When you pull into a parking space or up to the gas pump, your steering wheel is most likely turned off center. When you turn the key off abruptly before the power steering fluid equalized, it pinches the steering wheel against the ignition switch. Simple move the steering wheel clockwise or counter clockwise, which ever direction that will allow you to move the steering wheel. This will take the pressure off the ignition switch. Holding it, turn the ignition key to start. However, this problem can be compounded by a worn key and ignition tumbler making lock alignment difficult. A lot of keys weighing down the key chain can accelerate the wear of the ignition lock assembly.

▶ Is there a difference between repairing vs. maintaining a vehicle?

There is a difference. The short answer is that most repairs are done because something was found to be wrong. While maintaining means that services were performed before something was found wrong. A vehicle in good-repair is not the same as a vehicle that has been well-maintained. For more information read our noteworthy article here.

▶ What advice would you give me when shopping for a used vehicle?

Illinois is a buyer-beware state. That means that the buyer is solely responsible for the purchase of their vehicle. The state highly recommends that a professional be involved to inspect the vehicle before it is purchased. We offer a special “Possible Purchase” inspection to satisfy this need. I personally recommend that you buy popular, especially if a teenager is involved.  The more popular a vehicle is the more likely it will be cheaper to fix, parts will be more readily available and nearly anyone can fix it. Plus it is usually cheaper to insure.

▶ My exhaust smells (like rotten eggs), so has my catalytic converter gone bad?

The job of a catalytic converter is to take in the bad air (exhaust pollutants) from the engine and convert it into good clean air.  The amount of bad air coming from an average engine before 2007 is around 3%, after that it has dropped to nearly 1%.  Unless there is something wrong with the engine, the catalytic converter has little to do.  If you remember your high school chemistry, a catalyst is not used up in the process of the chemical reaction.  In theory a catalytic converter will last forever.So why does it smell?  That’s a good question.  The short answer is that all gasoline contains a small trace of sulfur.  When the exhaust stinks of rotten eggs, it is because the catalytic converter is being flooded with fuel and the amount of sulfur passing through has increased dramatically. Your catalytic converter is being overworked or cooked.  What you now smell is large amounts of bad air being converted (to help reduce emissions) at a very high rate (far greater than the recommended 3%), hence the high concentration of sulfur.  The catalytic converter is actually doing its job, but not for long.  A melt down will soon occur because of the tremendous amount of heat being generated by the excessive chemical reaction – think of the heat generated by lighting a match. What the rotten egg smell is really trying to tell you is that there is something wrong up ahead, from the engine.  The engine is adding excessive amounts of fuel (bad air).  A few possible causes are a leaking injector, malfunctioning fuel pressure regulator, slipped timing belt, coolant sensor out of range or lazy oxygen (O2) sensor.  The key indicator is that (LTFT) Long Term Fuel Trims will be out of range.  This over fueling, over time, will eventually destroy the catalytic converter.  Keep in mind that catalytic converters don’t just die, they are usually murdered and the fault should be found before a new catalytic converter is installed. The answer to a smelly catalytic converter is that it is working but is being over worked because the root cause (real problem) of over fueling (bad air) is flooding your catalytic converter.  

▶ Does the dealer have to do all my maintenance to keep my warranty valid?

No, you can choose where to have your vehicle serviced, as a matter of fact the law protects you in this area. Federal Law Prohibits New Car Dealers From Implying or Denying Warranty Service Because Scheduled Maintenance Was Performed At An Independent Repair Facility - Magnusen-Moss Act (1975) Title 15 - Chapter 50, Section 2301-2312Paul Stock
Owner at Stock's Underhood Specialists the best auto repair service Belleville IL has to offer since 1984. Providing professional, trusted auto repair service at affordable prices.

Buying A Used Car?


©2020 Stock's Underhood Specialists - All rights Reserved