Thermostat Fixes Transmission
Problem!
Recently a customer brought in their 1987 Chevrolet Celebrity
with a strange complaint. The customer reported that when driving the car
on the highway, the automatic transmission would shift normally and
go into overdrive with no problems. However, if the heat was turned on,
the car would soon come out of overdrive and shift to drive. During the
first road test with the heat on w found that the car was running
well and unfortunately the problem was not occurring. Upon road testing
a second time, the problem surfaced. Sure enough, the transmission
could be felt coming out of overdrive shortly after the heater was turned
on. Several of our technicians were discussing this perplexing problem
over morning coffee break. The technicians had developed a theory that
they wanted to test. Knowing that on many of today's computer controlled
cars, the car's computer will not engage overdrive unless a certain engine
coolant temperature is reached, they decided to test drive the car
with a scan tool to monitor the coolant temperature sensors reading. (The
scan tool is a device that we use to connect to your car's computer. It
allows the technician to see the same information that your computer is
seeing from all the vehicles sensors. This is very similar to the same
technology that aircraft use, better known as a flight data recorder.).
After connecting the scan tool to the vehicle we called up the datastream.
(The datastream is the name given to the list of both sensor inputs and
outputs that your car's computer is seeing and controlling.) While
driving the car and monitoring the datastream on the scan tool we noticed
that the coolant temperature was lower than normal at 160F. This would
seem to indicate that the car's thermostat had failed and was not allowing
the engines coolant to reach the normal operating temperature of 195F.
However, this still did not explain our problem. When the heat was turned
on, we noticed the coolant temperature dropped even lower. Normally the
coolant temperature of the engine does drop when the heat is on because
the coolant is now going through the heater core to provide heat for the
cars interior. (The heater core is actually a small radiator.) With coolant
flowing through both the radiator and the heater core there is always a
natural reduction in engine coolant temperature. However, on this car,
the coolant temperature is already lower than normal because of the failed
thermostat. Turning the heat on brought the engine's coolant temperature
to a very low level. As we monitored the coolant temperature an interesting
thing happened. When coolant temperature got down to 157F. The computer
commanded the transmission to turn off the overdrive gear. Take a look
at the data stream to see what we mean:
DATASTREAM ANALYSIS
**********WITH HEATER OFF*****************
Sensor Input or Output Current Reading
O2 (Oxygen Sensor) .321 millivolts
Loop Status Open/Closed Closed
TPS (Throttle Position) 1.27 volts
TPS% (Throttle %) 27%
IAC (Idle Air Control) 150 counts
Des Id ( Desired Idle ) 1100 RPM
MAF (Mass Air Flow to Eng.) 18 gams per sec.
Pulse Width (Fuel Injector On Time) 2.3 millisec.
Knk (Eng Knock Yes/NO) No
Prom Id (Program ID Number) 9247
TIME (Time Since Key On) 18:42
Batt (Battery Volts) 13.7
CTS (Coolant Temp) 162 F
BK (Brake Pedal On/Off) Off
CF1 (Cooling Fan 1 On/Off) Off
AC (Air Conditioning On/Off ) Off
VSS (Vehicle Speed Signal) 57 mph
O/D (Overdrive On/Off) On
DATASTREAM ANALYSIS
*********WITH HEATER ON************
Sensor Input or Output Current Reading
O2 (Oxygen Sensor) .632 millivolts
Loop Status Open/Closed Closed
TPS (Throttle Position) 1.09 volts
TPS% (Throttle %) 21%
IAC (Idle Air Control) 150 counts
Des Id ( Desired Idle ) 1100 RPM
MAF (Mass Air Flow to Eng.) 15 gams per sec.
Pulse Width (Fuel Injector On Time) 2.1 millisec.
Knk (Eng Knock Yes/NO) No
Prom Id (Program ID Number) 9247
TIME (Time Since Key On) 21:32
Batt (Battery Volts) 13.7
CTS (Coolant Temp) 157 F
BK (Brake Pedal On/Off) Off
CF1 (Cooling Fan 1 On/Off) Off
AC (Air Conditioning On/Off ) Off
VSS (Vehicle Speed Signal) 57 mph
O/D (Overdrive On/Off) OFF
As you can see, when the computer saw coolant temperature
get to 157F it shut down the overdrive gear in the transmission. Evidently
157F to 158F is the threshold coolant temperature value for overdrive operation.
The computer does not want the overdrive on with a cold engine because
this could cause a cold engine to stall. We had just discovered a small
piece of this car's computer's program instructions. This brings out an
interesting point. This is a perfect example of what we call computer "Strategy".
Strategy is the term used to explain the computers program instructions
or operating philosophy. Strategy is never published by automotive manufactures
because it is believed to be top secret information. You will never find
this information in a vehicles service manual. They call it proprietary
information. They do not want it published because they do not want other
manufactures to learn their programs. This creates problems when trying
to service cars because we could really use this information to help us
diagnose vehicles faster in order to reduce the time to diagnose problems.
Less time to diagnose means less expense to the customer.
How do we know what the computer should do when a sensor
reports a certain value? We face this problem almost daily. We will be
trying to diagnose a car and we will be looking at datastream information
like the above data. We will see the computer turn on a certain item. Was
it supposed to turn on that item at that time? What sensor data does the
computer look at to make that decision? We don't know! Technicians nationwide
don't know! Only the writer of the program knows and he's not talking.
Just another example of how complex automotive diagnostics can be. Just
so you know.
The Shop's Schedule Is
Currently Full, However
If You Could Drop Off
The Car....
If you have called our service department recently and
needed to schedule some normal maintenance, we probably assigned you an
appointment based on our current schedule which is a few weeks ahead. As
you know, the service department has been quite busy lately. In some cases,
when your vehicle is in need of some more urgent service, for example:
your car won't start, large oil leak, etc., we will advise you to leave
the car with us for a day or two and we will make every attempt to get
you back on the road again in as short a time as possible. How can leaving
the car for a day or two allow us to look at it any sooner than our two-week
schedule? If you leave us the car, we can start to work on it during authorization
hold times. In plain English, when a technician is working on a car that
was scheduled for that day he may find other items that need attention
that were not booked. The technician will have Glenn call the customer
for authorization. While we are waiting for that customer to call back
we can attempt to begin work on unscheduled cars that have been dropped
off. In addition, if your car has an urgent problem and your schedule
does not allow you to be without it, we have a local rent-a-car company
that we can refer you to that has competitive daily rates. This way while
we're working on your car you still have transportation.
A New Face In The
Service Department
We would like to introduce Sue Blais. Sue has been
given the responsibility of service
advisor. She has a strong
automotive background and is very helpful in answering service questions.
We have already received quite a few compliments about Sue
from our customers. She is assisting Glenn in the service department with
appointment booking, estimates, incoming service calls for
customers checking the status of their vehicle, repair order writing
and general automotive service advise for our customers. Sue's presence
will reduce the average time customers are waiting, in person or
on the phone, to speak to someone in service. If you have a technical
question or other need. Glenn and Mark are, of course, always
available. |
The Parts That Someone Paid
For
That Were Never Installed.
Recently a technician from a local new car dealership
stopped by with a trunk full of brand new parts that he wanted to sell.
At first we were suspicious as to how this technician acquired the parts.
After all, a technician selling parts out of the trunk is not the norm.
At first we thought that maybe he, or someone else, had stolen them out
of the car dealer's parts room. The technician replied that the parts were
not stolen and he seemed confident that he had proper ownership of them.
As we questioned him further, the story got dramatically worse. The parts
were not stolen from the parts room but they were stolen from customers.
Let's explain. Like many new car dealerships, this technician is on the
"flat rate system". In the flat rate system, the technician is paid a certain
amount of time for each particular automotive service procedure regardless
of how long it takes him. For example, in many new car dealerships the
flat rate time for an oil change service is a 1/2 hrs labor. In other words,
the technician gets paid for 1/2an hours labor regardless of whether or
not he completes the job in more time or less time. If he does the job
in twenty minutes he gets paid for thirty minutes. If he takes a whole
hour to do the service he still only gets paid for the 1/2hour. That's
the flat rate system. One of the many problems with this system is that
the system promotes speed as opposed to quality. This is where his parts
came in. This technician told us that because he is on the flat rate
system the technicians don't always put in the parts they're supposed to
because they are trying to save time or even "make" time. How do you "make"
time? If you perform a procedure that pays 1/2 an hour but you complete
it in only 15 minuets, you just "made" 15 extra minutes. If this type of
"making" time can be done all day, before you know it, the technician has
turned a forty-hour work week into a fifty-hour work week, or more, yet
they were only working on cars for forty hours. The more time they can
cut the more they can increase their hourly pay at the end of the week.
Many times this technician would perform a transmission flush service and
not change the transmission filter. He would take the new filter and put
it in his tool box. Meanwhile, the customer still gets charged for the
filter on his repair bill. Among the other parts in his trunk were brand
new fuel filters, spark plugs, and timing belts. Same story. A customer
comes in for a timing belt replacement. If the belt is not broken and the
customer just wants it changed for preventive maintenance he would not
install the belt. Once again the customer paid for the belt and the labor
to install it and got neither for his money. We questioned him as to whether
or not the service manager of his dealership new he was doing this. He
was quite sure the manager had caught on but he and the other technicians
doing this are not getting reprimanded because for each part they sold
on a repair order, the service manager and the technicians are getting
a 3% boost in pay based on the parts sold. (See Giammalvo Quarterly Spring
1990 for an interesting article on parts commissions.) Anyway, we told
the technician that what he was doing was called FRAUD, and that as far
as we were concerned the parts in his trunk were stolen. Stolen from customers!
In one way, we dislike bringing you the "bad news items" about the automotive
industry but at the same time we feel it is more important for you to be
aware of these things so you can be more conscious about your vehicle's
service needs if you are out of the area and are not sure who you can trust.
Obviously this does not mean that all new car dealerships operate in this
manner, but you should be on your guard when receiving any type of service
today, automotive or not, especially when you are unfamiliar with a particular
facility. As a value added service to you, when you are planning a trip
out of town, feel free to call our service department and we will supply
you with a list of quality competent service providers that are in the
area of the country in which you will be traveling. We will find other
shops, like ours, that are members of the Automotive Service Association.
Also, if you find yourself in need of help anytime you're out of town,
and can get to a phone, give us a call. You can be sure we'll place you
in trusting hands.
In Passing
We are deeply saddened by the death of customers,
Albert J.
Lamoureux, Regis Spangler,
Harold Hurwitz, Margaret Linney
and Capt. Ed Sanchez Jr.
The Lamoureux family has been customers of ours for quite
some time now. Al was the former funeral director and embalmer of the Lamoureux
Funeral Home for 47 years until his retirement due to illness. He is survived
by his wife Lillian.
Regis Spangler was born in Pittsburgh and lived in Fairhaven
more than 50 years. He was a self-employed mason for many years.
He received the National Defense Medal, the United Nations Service Medal,
three bronze service stars and two overseas bars.
Harold Hurwitz was a customer and the attorney for our
dealership for many years. He was a graduate of New Bedford High School
and attended Colby College. He received his L.L. B. from Boston University
Law School.He was a founding member of the law firm Hurwitz and Hurwitz
of New Bedford. The firm is now being run by his son Barry Hurwitz.
Mrs. Linney also a customer, lived most of her life in
New Bedford. She was a member of the Daughters of Isabella; the Catholic
Order of Foresters; the Council of Catholic Women and the St. Julie's Ladies
Guild.
Capt. Ed Sanchez. Jr. was the owner and founder of Buzzards
Bay Realty. From 1976 to 1986 he was also president and general manager
of Sanchez Marine Shipbuilding and from 1964 to 1986, he was co-founder
and general manager of Sanchez Marine Services and founder of Sea Ed Marine
Inc. He also worked for Pleasant Street Development Corp. and Atwood Crawford
Woodturning Co.
As of this writing we also learned of the passing of Larry
Demello. The Demello's are also long time customers of Giammalvo's. He
will be missed.
Our heartfelt condolences go out to all the above
families.
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