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Friday, April 11, 2014

Dr. Gizmo Column



"Dr. Gizmo"
By Phil Arendt

Reader Looks For Up Sell Tip
Question 1
When replacing struts and shocks is there any unnecessary work I should avoid?  P.M., email

Answer 1
There’s nothing better than properly aligned wheels.  You definitely will notice an improvement in the ride and handling after an alignment.
When replacing shocks and struts the wheel alignment should be checked and adjusted.  Nothing else is necessary unless a technician finds excessively worn tires and worn parts in the steering and suspension. These parts should be replaced as necessary before the wheels are aligned.

Valve Seats Causing Big Trouble
Question 2
I recently purchased a Dodge 1500 Van with a 5.2-liter engine.  It now has 111,000 miles.  Shortly after the purchase the engine began to run rough at an idle.  Also, the check engine light turned on.  When cruising, the engine felt smooth.
I took it to repair shop.  A mechanic has done many tests.  He checked an ignition coil and found it was bad.  He also found codes in the engine computer for misfires in cylinders three and four.  He checked the spark plugs and ignition wires.  They are good.  He also checked the compression in all the cylinders and looked for air leaks at the intake manifold.  After all of this work the engine misfired at the same two cylinders. 
He thinks the trouble is in the valves.  His shop manager took it to another shop that had some special equipment that could look inside the engine.  They examined the valves without taking the engine apart.  They found the seats in the valves are loose.  My shop now says the cylinder heads might need replacement.  They won’t know for sure until a machinist examines them.
Does this seem right to you?  H.K., email

Answer 2
I’m sorry to hear that your recent purchase is troublesome.  It is indeed possible that the valve seats have separated from the cylinder heads or are excessively worn.  It appears your shop wants a machinist to examine them to determine if they can be repaired.  If so, it will not be necessary to replace them.  If they can be repaired the machinist will completely overhaul them if this is the option you choose.  Another option is to install remanufactured cylinder heads from a company that specializes in this type of work.  Once your shop provides estimates for both options you’ll decide which option is best.

Faulty Hydraulic Parts Hinder Clutch Operation  
Question 3
A week and a half ago the clutch started slipping in my 2001 Honda CR-V and needed replacement.  My repair shop replaced it and the new clutch was working great. 
Over the weekend the clutch started acting up.  When I pushed down the pedal the clutch seemed as though it was not fully releasing.  Also, it was difficult to shift into gear and once in gear it’s difficult to shift to the next gear.  I ended up leaving the car in my shop parking lot.
My car has 199,000 miles on it.  I’ve owned it since new.  The clutch that was just replaced was the original clutch.  Is there something wrong with the installation of the clutch or is there another problem?  S.H., email

Answer 3
Congratulations for driving the vehicle 199,000 miles on the original clutch.  Some drivers go through two or three clutches in that mileage.
This issue likely is caused by a hydraulic failure of the clutch master cylinder or clutch slave cylinder and not a failure of the clutch and related parts.  When you press on the clutch pedal, hydraulic pressure disengages it.  If a seal has developed a leak in either hydraulic part the clutch may not release. 
A technician needs to determine which part has failed.  This condition more than likely is caused by a hydraulic failure but if parts recently installed have failed the repair should be covered by a warranty.

Door Windows Fail To Operate As Designed
Question 4
My 1994 BMW 325i convertible has an unusual problem that I hope you can help me with.  I’ve owned this car for 10 years.  Since my purchase, when I open the driver or passenger door, the window has opened about an inch or so as soon as I lifted the handle.  Recently, the windows have stopped doing this.  They remain in the fully closed position instead of dropping.  This causes the windows to rub on the top. 
I went to a repair shop but they did not know what causes the issue.  They think there might be a faulty relay or switch but they need to dig into the doors to determine the cause of the problem.
I really like my car.  It’s in good condition for its age.  Do you have any suggestions?  K.T., email

Answer 4
It’s time for a new car.  All kidding aside finding replacement parts to repair the condition might become an issue but let’s not worry about that yet.  The trouble more than likely is caused by faulty switches in the door latches.  When you raise the door handle a switch in the latch signals the window motor to open.  Unless there is an issue such as a poor connection in the wiring the likely repair is to replace the latch assembly. 
Ask your favorite shop to give this some consideration.  If a technician verifies this is the cause of the problem, the availability of replacement parts might become an issue.  Let’s hope not.

Trans Fails After Hitting Snow Bank
Question 5
During this last round of snow my 2001 Jeep Grand Cherokee Laredo slipped into a snow bank and was stuck.  The snow bank was as hard as rock.  I managed to get out but after that the transmission would not shift from second to third gear. 
It shifts fine from first to second but after that it’s as if it’s in neutral.  If I manually shift from first to second it stays in second gear and then goes into neutral even though it’s in drive.
I stopped at a repair shop where a mechanic raised the vehicle to see if there was any damage.  He did not find anything wrong.  He suggested taking the vehicle to a shop that does his shop’s transmission work.  He thinks the transmission has an internal problem.
Once the other shop looks into the trouble is there anything I should watch out for?  M.S.J., email

Answer 5
Winter is tough on vehicles.  You are lucky the vehicle did not sustain body or undercarriage damage to the suspension and other parts.  Snow piled along roadways can be solid as concrete. 
When you visit the transmission shop make sure to tell them exactly what happened.  A technician will do a visual inspection of the undercarriage and transmission to make sure the first shop did not miss something.  If there is physical damage that has caused an issue you might consider filing a claim with your insurance company.  If there is no physical damage the shop will inspect the fluid and do a number of tests including a road test to experience the condition.  Once tests are completed the diagnosis might be that indeed there is an internal problem.  If they find that the condition is due to a failure of the valve body it’s likely no overhaul is needed.  If there is a failure deep inside the unit they will suggest an overhaul or replacement with a remanufactured or used transmission from a salvage yard. 
If your vehicle has over 100,000 miles more than likely an overhaul or replacement is due.

Shop Policy Forbids Installation Of Used Parts
Question 6
My 2006 Volkswagen Jetta TDi with an automatic transmission and 133,000 miles lost some power as I was driving on the highway during a vacation trip.  Also the check engine light turned on.  I went to a shop where they found a code for booster pressure.  After more investigation they disconnected the cooler for the exhaust valve because something inside was broken.  They said I could drive but the engine would not have as much power.
Now I’m home and took the car to a repair shop.  I told them what happened.  After doing some tests the technician found the same code as before.  He also said the turbo was not kicking in.  He wants to replace it but it’s expensive.  When I asked him if a used part would work he said that he does not install used parts due to warranty issues.  He said that he could install one from a company that rebuilds them.  It’s their company policy.  
In the past I’ve purchased used parts from a salvage yard with great success.  Will a used turbo unit work okay in my car?  M.I., email

Answer 6
Sure a used turbo-charger from an auto recycler will probably work fine.  It might even have a warranty.  However, if your shop’s policy is to not install used parts there is nothing you can do to change the policy.  You can argue and complain about the issue, but it appears you will have to search for a different shop that does install used parts.              

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 P.O. Box 548, Cary, IL. 60013 or e-mail address drgizmo@hotmail.com.  01/27/2014 ® DR. GIZMO © 1989 - Present

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