Before consumers noticed sport-utility vehicles and minivans were
sweeping the market, collision-repair shops were already knee
deep in major and minor repairs. The problem: Repairs on these
currently popular alternate passenger vehicles aren’t always run
of the mill. Techs who find themselves involved in the repair
of one can expect difficulties in diagnosing the cause of some
electronic problems, finding some replacement parts and servicing
particular mechanical systems.
To help ease the repair difficulties you’ll undoubtedly encounter
when one of these trendy vehicles finds its way into your shop,
check out the following technical trouble spots and tips.
Technical Trouble Spots
Mechanically, these alternate passenger vehicles incorporate the
latest in drive- and power-train applications. For example, Toyota’s
Previa is designed with a degree of aircraft technology – the
water pump and cooling fan are designed to work in unison through
a jack-shaft arrangement required by its near-mid-engine mount.
Despite such high technology and the complex repairs it requires,
ordinary services, like oil and filter changes, are actually easier
on the Previa.
Though ordinary servicing may actually be easier on these sport
utilities and minivans, complex electronic systems have made diagnosing
some problems next to impossible.
A few years back, the Ford Aerostar featured electronic all-wheel
drive, which proved somewhat reliable. In the Eastern flat- lands,
the quick-to-react traction control worked well. However, in some
of the high-altitude mountainous regions, the module failed to
engage the all-wheel drive in severe weather – when it was needed
most. In such situations, the “Check 4WD” light illuminated.
When these vehicles are brought into the shop, however, self-diagnostics
is limited on most aftermarket scanners to the basic essentials.
Any fast codes not residing in the directory for engine systems
will not be available to help troubleshoot the all-wheel-drive
problem. Shops found that connector problems were the biggest
cause. Other times, the problem just went away after the vehicle
was driven awhile, and many service shops have attributed this
to mechanical or hydraulic difficulties.
Another electronic problem on the Ford Aerostar involves the digital
dash displays, a popular option since 1986. As with many other
similar components on many other vehicles, the chance that this
dash display will make it
to 100,000 miles without a problem is slim. Voltage overloads,
dust conductivity and static damage are among the problems found
by shop technicians. However, when such problems lead to repairs,
shops looking for a used unit to help defray costs have found
that most salvage yards are out.
A Few Tips for Techs
Eventually – if it hasn’t already happened – one of these alternate
passenger vehicles in need of repairs will find its way into your
shop. When you see those high-mounted headlights and expansive
bodies, remember these tips:
- Chevrolet Astro: Late-model Chevrolet Astro vans use
a high-pressure pump to charge the multipoint injection system.
Though leaks aren’t the real problem with the umbilical-designed
injection system, which uses check valves and plastic lines, Chevrolet
dealers have a few bulletins to refer to when troubleshooting.
Techs examining any complaints should start with the pump, since
this is usually where most no-starts are solved. Be careful to
install the correct pump part number – this series fuel system
won’t work with a standard multiport pump. - Isuzu Trooper and Trooper Two: Late ’80’s Isuzu Troopers
and Trooper Twos have been known to overheat at the drop of a
hat, and heater-core leaks can produce air pockets that lead to
head-gasket failure. Some of these overheating complaints could
be caused by cylinder-head growth problems, which permit the head
to loosen up on the cylinder block and to actually chafe the gasket
into failure. - Ford Explorer: Another popular sport-utility vehicle,
the Ford Explorer, can have intermittent hard starts that dealerships
may never find. Check for a corroded wire harness at the E.D.I.S.
terminal lugs at the weather-resistant connector. Green powder
means you should upgrade to a new corrosion-resistant connector
available from Ford. The company will sell you the wire by the
dozen only, so make other Ford Explorer customers aware that you
have the supplies needed to repair their hard starts. - Plymouth Voyager and Dodge Caravan: In these two alternate
passenger vehicles, electronic problems involving computerized
overcharging conditions are hard to diagnose correctly.Early models, manufactured with engines other than Chrysler’s
own, had few mechanical difficulties. However, Chrysler’s 3.0-
and 3.3-liter engines have been plagued with various engine noises,
sometimes caused by factory fitting of mechanical parts.But the problems spread further than under the hood. Rear-door
latch problems have been documented often – so much so that a
recall is in effect; fuel-pump failures are the biggest problem;
and emission violations are so frequent that I/M 240 lanes choke
up quickly when a few early models (’82 to ’85) await inspection
one after the other.Shop Solutions
Although the traditional mechanical and electronic failures techs
find in most passenger cars also appear in the minivan/sport-utility
set, they’re frequently seen at high-mileage intervals. For those
ailments not common on traditional vehicles, techs have discovered
the repair cures themselves – experimenting in the back rooms
of dealerships and garages throughout the nation.For any shop not looking to experiment, subscribing to a technical-information
system that includes current service bulletins would be a smart
move. Such information will keep you up to date on the reoccurring
minivan/sport-utility problems you may one day see in your shop.
Specialized technical training will also help in understanding
the complex systems you may encounter.If your shop has already seen and repaired these popular alternate
vehicles, don’t get too comfortable. New entries from Kia, Mercury
and Mercedes mean that the demand for this series of vehicles
is continuing – and so are the repairs.Bob Leone is a contributing editor to BodyShop Business.
Vehicle Checkpoints
Trouble spots on minivans and sport utilities are often different
than those on traditional passenger vehicles. For example:- Unlike traditional passenger cars, sport utilities beg to
be driven hard and, in most cases, are. Shops working on this
breed of alternate passenger vehicles will find bent control arms;
damaged stabilizer bars and fixtures; wrecked torsion bars; and
some spring problems, such as spring distortion, that require
spring replacement at all four corners. - On Nissan Pathfinders, water in the E.G.O. sensor will set
Code 33 and force any service department into a late-night session
if the techs aren’t up to date on their technical service bulletins.
Weatherproofing the harness and adding a splice upgrade should
complete the repair. - Keep in mind the owner’s purpose for his alternate passenger
vehicle. Perhaps Mr. Jones uses his Nissan Quest for a mail delivery
service and has a tendency to load the vehicle like you would
a truck. While the Quest can handle the heavy load, its brake
system will probably suffer from a stop-and-go routine, especially
if it’s on a rural route. - Like on the Quest, the brake systems on Chevrolet Blazer S/T
models suffer in similar situations. In less than several thousand
miles, packed-in mud in the rear drums and brake mechanism can
abrade the lining material down to the bonding plate. Loss of
ABS sensors located on the wheels can also occur because of mud
buildup and abrasive material on the tone wheels. - Springs are another common source of driving difficulties
on minivans. Some material deficiencies can allow for spring-rate
discrepancies, and on occasion, strut bearings or mounts may also
fail. Upgrading to stiffer springs and related handling packages
has become a common service repair. - Tire wear is another trouble spot and possible source of handling
complaints. On sport utilities and minivans, the combination of
uneven loading, multiple tire configurations and individual driver
habits allows for various tire scrub patterns. Running different
tow and camber settings is sometimes the only way to solve the
many problems you’ll encounter. - Be prepared for special repair situations on alternate passenger
vehicles equipped with winches, wheelchair lifts and other accessories
not ordinarily found on traditional passenger vehicles.
- Unlike traditional passenger cars, sport utilities beg to