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Friday, April 12, 2013

Dr. Gizmo Column

"Dr. Gizmo"
By Phil Arendt

New Battery Is Defective
Question 1
I have a 2003 Jaguar S-Type with a 3.0-liter engine.  The trouble is the battery goes dead.  I can’t drive the car because several warning lights turn on in the dash and the engine stalls.  The first time this occurred the car was towed to a shop that has been servicing it for the last few years.  They tested the battery and found it defective.  They replaced it but after driving about 30 minutes all the warning lights in the dash came on and the engine stalled. 

My shop picked up the car and found the battery was dead again.  They checked for bad ground connections.  They did several tests and found multiple problem codes in the computers.  They also checked the starter and alternator but they don’t know why the battery dies.  They said the problem codes more than likely are caused by low battery voltage but they don’t know why the battery dies when everything checks okay. 

I like my car.  It’s in great condition.  I don’t want to trade it in at this time.  Do you have any suggestions?  L.R., email

Answer 1
There might be a simple solution.  From what you describe your shop has done a lot of work including replacing the battery.  The technician has not found any problems during all of his testing.  Despite this, the brand spanking new battery will not hold a charge even though tests show the alternator is doing its job of providing a proper charge to it. 

Perhaps the trouble is right in front of your technician.  He might consider testing the new battery.  Perhaps it is defective.  If so, installing another will put your vehicle back to full duty.

Trapped Air Impairs Heater
Question 2
I have a 2006 Honda Pilot with a 3.5 engine and very little heat from the front and rear heaters.  The problem began after a hose leaked.  My repair shop replaced it.  They said it looked like a mouse chewed on it and caused a leak.  When they replaced the hose I had them flush the antifreeze.  Since then the heater only produces warm air and not hot air as it did before this incident.  I have returned to the repair shop twice for this problem.  At first they told me there might be air trapped in the system.  Now they say there might be something blocking the cores in the front and rear.  They might need to replace them. 

My car only has 17,000 miles on it.  It’s like new.  Have you ever heard of anything like this before?  E.K., email

Answer 2
Sure, mice can do a lot of damage to a vehicle.  It’s a common problem especially in vehicles that don’t get much use.  Be this as it may the current condition more than likely is caused by air trapped in the system and not by material in the heater cores.  Your shop may need to create a vacuum in the system to draw any air that is trapped.  Once air is replaced with engine coolant heat should blast from the vents.
 

Incorrect Brake Parts Cause Big Trouble
Question 3
I have a 2007 Dodge Durango SXT that needed new brakes.  For years I have replaced brakes on all of my cars and never have I run into a problem.  Recently I replaced the front brakes and calipers.  After the work I bled the system.  The trouble is that now the brake pedal does not have any pressure until I pump it a few times.  The pedal feels hard with the engine off.  When it’s on the pedal drops and I have to pump it.  When this first happened I replaced the master cylinder but this did not solve the problem.

I took the vehicle to a repair shop to have them bleed the system.  Their work was in vain.  What do you suggest I do?  S.K., email

Answer 3
Don’t drive your SUV until this is repaired.

Since the trouble appeared after installing new calipers consider there is something wrong with them.  While this might seem a stretch but perhaps your auto supply store sold you the wrong parts.  If so, I think you know what action to take.


New Engine Suffers From Gas
Question 4
I own a 2004 Jeep Wrangler Sport with a 4.0-liter engine.  I purchased it last spring with 46,686 miles and a blown engine.  The previous owner lived in Idaho and it was parked in a barn for a nearly three years.  The exterior and interior are like new.  I purchased it dirt cheap.  Since the purchase it’s been in my garage.

Over this past winter I replaced just about every suspension part, renewed the brake system, replaced the entire exhaust system and installed a remanufactured engine from a well-known company.  The trouble is that the new engine idles rough.  Other than this it runs good.
I have checked the compression, vacuum and taken it to a repair shop for diagnosis of the trouble.  The guys at my shop have done all kinds of tests but they can’t find anything wrong.  I even called the company that remanufactured the engine.  They suggested a shop they trust to look into the trouble.  Their shop found no problems.

The company won’t exchange the engine because their shop found no problems.  I’ve only driven about 65 miles since I bought it.  I’m at a loss.  Do you have any suggestions? W.B., email

Answer 4
Never fear Dr. Gizmo is here.  Since the vehicle has not been in use for many years I suspect trouble in the fuel system.  Over the years the fuel the previous owner left in the vehicle has basically spoiled.  Consider flushing the system, adding a fuel conditioner to the tank and fresh gas.  Once a tank or two of fresh fuel has run through the system the engine should run as designed.

Additionally, check the position of the engine mounts.  It is possible they need realignment.  Sometimes when replacing an engine the powertrain needs a little adjustment and misalignment can cause vibration in the passenger compartment, steering wheel and sometimes in the brake and accelerator pedals.

Fluid Flush Needed
Question 5
I have an intermittent problem with my brake warning light coming on while driving my 1999 Acura Integra with 122,000 miles.  The fluid level seems fine.  Usually when I apply the brakes the light goes off but not always.  It may come on again after braking and then off again when using the brakes. 

Today, it was on all the way to work which is about a 17 mile drive over 45 minutes.  On the drive home the light was not on.
The braking and pedal feel normal.  Do you have any idea what the issue is? R., email

 
Answer 5
Your car is winking at you.  Be this as it may since the brakes seem to work fine this likely is not a serious issue.  More than likely the sensor in the brake master cylinder has a fault.  Sometimes flushing the hydraulic system and cleaning the sensor resolves a winking brake warning light.

Ask your favorite technician to consider these suggestions the next time you visit his shop.


Surprising Find In Newly Purchased Used Vehicle   
Question 6

Recently, I purchased a 2000 Jeep Wrangler with a 4.0-liter engine, 5-speed manual transmission and 110,000 miles.  I bought it from a private party in a different state.  It’s in great condition, runs fine but the check engine light was on when I purchased it.  The previous owner told me the light has been on for as long as he has owned it.  He purchased it two years ago.  He said it has never given him any trouble.

I took the vehicle to a parts store to have the computer tested.  The parts person connected a scan tool to the vehicle but he said it would not communicate with the powertrain computer.  He suggested that I go to a dealer to find out why.

I went to a dealer.  After several tests their mechanic determined that the computer is not the correct one for the vehicle.  They said it needs replacement.  I did not have the work done but for the car to pass the state emission test I have to get the issue repaired.  How is it possible that the car will run with an incorrect computer in it?  Are they trying to pull something over me?  R.W., email

Answer 6
Over the years I have experienced situations such as this many times.  It is possible a computer from an older, newer or similar vehicle was installed.  This could occur at a mechanical repair shop, body shop, private seller party or salvage yard. 

At this juncture it’s time to replace the unit.  There are some alternatives that might save a couple of bucks.  Ask your favorite dealer or independent repair shop if they will install a remanufactured unit or even a used unit from salvage yard for these units likely will cost less than a brand spanking new part.  Also, once the correct computer is in your vehicle you might find engine performance is even better.

Thanks for all of your great questions.  Dr. Gizmo can’t wait to answer more.

Phil Arendt is a columnist, consultant and A.S.E.-Certified Master Technician.  Readers may send questions to Dr. Gizmo at P.O. Box 548, Cary, IL. 60013 or e-mail address drgizmo@hotmail.com  03/25/2013 ® DR. GIZMO © 1989-Present

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