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Monday, January 7, 2019

Dr. Gizmo Column


01/08/2018

“Dr. Gizmo”
By Phil Arendt

Simple Repair Turns Into Complex Operation   
Question 1
I was driving on the highway in my 2011 Kia Optima EX with 121,000 miles and a 2.4-liter engine when it shut off as if I turned off the ignition.  I tried to restart but I only heard a click.  After several attempted starts I smelled an electrical odor.  I checked under the hood and saw smoke coming from the starter.  I had the car towed to my home.  I replaced the starter but I’m having the same trouble.  The engine does not turn when I hit the start button.  I just hear a click at the starter.  It gets very hot. 
I have checked all the fluid levels.  The oil level is down about a half quart.  All the other fluids are full.  I also exchanged the starter with the same results.  Is there a relay or something that is causing this issue?   E.H., email

Answer 1
It’s not likely a relay or starter motor is the cause.  What might be the trouble is the engine has an internal problem that prevents it from turning when the starter engages to crank to start.  If you have the tools to turn the engine by hand you might find the engine is seized or exhibits excessive rotational resistance.  If so it’s time to send the vehicle to a shop for further examination.
The engine might need disassembly to determine the cause of the issue.  It might need replacement.  Also, consider sending the vehicle to a dealership.  It’s possible with proof of regular and frequent preventive maintenance you might receive repair assistance from the manufacture.  It is unusual for an engine to seize at this mileage.

Replace Or Repair Transmission
Question 2
The transmission in my 2001 Chevrolet S10 with a 2.2-liter engine constantly downshifts from fourth gear to third and back to fourth gear if I apply a little pressure on the gas pedal.  I went to a shop to have it flushed and a new filter.  This did not cure the trouble. 
I went to another shop where they checked for codes.  None were found.  They suggested an overhaul.
My truck is in great condition.  I’ve owned it since it was new.  I have followed the factory service schedule.  It hasn’t given me any trouble until now.  It has 169,144 miles.  Do you think an overhaul is needed or is there an alternative repair that will cure the trouble?   S.S., email

Answer 2
The fact there are no malfunction codes is unusual.  Generally, an issue such as this results in some sort of code.  Perhaps a reference signal does not meet software criteria to turn on the light.
As for the trouble, pressure tests might find a lack of hydraulic pressure.  If so, it’s possible a seal is leaking or perhaps excessive wear of the hydraulic pump is causing the trouble.  It’s possible a valve bore is excessively worn. 
It’s possible replacing the valve body will cure the issue but at this mileage there no doubt is wear of clutches and other parts.  It might be wise to compare the cost of an overhaul and a remanufactured transmission.  Since your vehicle is in top condition if you intend to keep it for a few more years, replacing the transmission might be the best option.

Worn Part Causes Vibration
Question 3
Recently, a shop replaced the seals on the oil pump.  I have a 2000 Honda Accord with 156,000 miles and a 2.3 engine.  After the repair I feel a vibration from the engine that I did not feel before.  I returned to the shop.  They checked over their work but said everything was done properly.  I went to another shop to have them check it over.  They said they feel the vibration but found nothing wrong with the first shop’s work.
I have owned this vehicle since it was new.  I have taken great care of it.  I have never felt this vibration before.  I feel it especially when the car is idling in reverse gear.  It has an automatic transmission.  What do you suggest I do next?  Could something in the transmission cause this?  Do you have any idea what causes the vibration?  T.L., email

Answer 3
Don’t fret.  It’s not likely the transmission has an issue.  The fact the vibration developed after the oil pump repair raises suspicion that lends to this task.  It’s not likely the oil pump is the cause.  More than likely the issue is due to misalignment of motor mounts or perhaps a motor mount needs replacement. 
This condition likely is not due to technician error.  It’s likely due to a worn part being disturbed in the process of repair.  Sometimes a worn part fails but neither shop found a failure.  Parts such as motor mounts adapt to a specific shape after many miles of use.  They are constructed primarily of rubber.  Once it adapts to a specific shape, when a technician removes it and then reinstalls it does not conform well to the mounting point on the engine cradle and engine.  This causes vibrations from the engine to transmit to the frame and body.  The fix for this condition might be installation of a new motor mount.

Wiggle and Giggle Will Find Cause
Question 4
Sometimes the dash warning lights come on, the speedometer quits and the engine cuts out and sometimes stalls in my 2009 Chrysler PT Cruiser LX.  When this happens the engine restarts without any problem and the dash appears normal.  This usually happens after I have driven 20 to 30 minutes.  I went to a local repair shop that has serviced the car several times over the years.  Their technician drove the vehicle for two days but the car acted normally.  He also did several tests but no problems were found. 
The trouble seems to be getting worse.  I fear I will be stranded along the road.  Can you help?  H.G., email

Answer 4
I’ll do my best.  Your technician found no problem codes and the vehicle never displayed the condition during road tests.  This makes it difficult to find a cause.  Be this as it may, it’s time to look for loose and corroded electrical connections.  Wiggling wires might find the cause is a loose terminal in a plug.  It’s possible worn contacts in the ignition switch cause all the symptoms. 
Ask a technician to consider these suggestions.  Give authorization for diagnostic time but limit time to a reasonable amount.  Perhaps an hour or a little more would be agreeable to you and the shop technician.  Repair might be as simple as repairing a corroded terminal which might only take a few minutes to repair.

More Work And Expense Than Anticipated
Question 5
I have a 2012 Dodge Grand Caravan SE with 16 inch tires and wheels.  I recently learned that 17 inch wheels and tires were an option back when I bought the vehicle.  I went to a shop to have new 17 inch tires and wheels installed.  They verified that the tires and wheels were optional for my van.  I was told that they could install the requested tires and wheels but the computer would need reprogramming.  Also, they insisted that I have them install tire pressure sensors on the new wheels or they would not do the work.  I checked with another shop.  They said the same thing.  The cost for reprogramming and sensors was outrageous.  I had them install the tires, wheels and sensors without programming.  Now the speedometer is off and the engine and transmission are not performing normally.  They warned me about this. 
In the spring I intend to return to the 16 inch tires and wheels.  Is it necessary to reprogram the vehicle twice a year when I switch between tire and wheel size?  D.B., email

Answer 5
Yes indeed switching tire and wheel size requires engine control module programming.  The difference between sizes alters transmission shift points, fuel economy, speedometer accuracy, exhaust emissions and more.  To bring everything into factory specification it is necessary to program the engine control module.  Since you intend to switch tires in the spring and fall expect programming to be a twice year procedure if you want the vehicle to operate as designed.

Reset Might Do The Trick
Question 6
I have a 2004 Mazda MPV LX with a 3.0 motor.  I’m pretty good when it comes to fixing my family vehicles but this one is beating me up pretty bad. 
The engine was missing and the check engine light was on and flashing.  I went to an auto parts store for a test.  The employee found misfire codes and lean codes. 
I replaced the spark plugs, ignition coils and oxygen sensors.  I also replaced a cracked vacuum line and cleaned the air flow sensor. 
The engine runs great now but I’m still getting a lean code.  I’ve checked all over the engine for air leaks with carburetor cleaner and propane but I can’t find a leak.  Before I take this problem to a shop, is there any way to reset the fuel mixture computer without using a scan tool or computer?  L.W., email

Answer 6
Yes.  This might do the trick.  Remove the cables from the battery.  Bring both cable clamp ends together with tape.  Wait about 30 minutes.  Reconnect the cables to the battery and go for a drive at various speeds on secondary roads and highway.  This might reset the fuel trims and you’ll be good to go.  If this does not cure the issue, it’s time to visit your favorite shop.

Thank you for all the 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 his e-mail address drgizmo@drgizmo.ws.  01/08/2018 ® DR. GIZMO © 1989 – Present  

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