(AOL Autos) -- A small bodywork scratch: $1,500. An exhaust valve replacement: $3,500. A new trunk-release switch cover: $150.
Steam coming out of your exhaust could be nothing or it could be a sign of some serious repair bills ahead.
All are actual repair costs recounted to AOL Autos from drivers who took their cars to their auto shops with seemingly minor problems only to be hit by disproportionately expensive repair bills.
And unless a motorist wants to fix the fault themselves or buy a new vehicle, most drivers in similar situations are left with little choice but to stump up the cash and grin and bear it. Or at least grit their teeth, hold their tongue, and then bear it.
We take a look at some common repair jobs that can add up to a pretty penny.
Beyond the bumper
Deana May, at Los Angeles, California-based AC Auto finishing, knows what surprises can lay in store for a customer once they get behind a simple surface scratch or abrasion.
"It's a scary thing -- looks can be deceiving. You can do an estimate on a front bumper then take it off and behind it there's all kinds of damage. Low-profile cars with low-profile tires go over a bump or up a driveway, they don't take an angle, often they need a whole new front end."
May says they see a lot of this type of problem at her shop and says a Lotus driver last month was quoted a cool $5,400 to repair his car, though from looking at it she couldn't tell there was much wrong.
Also she warns of the dangers -- and costs -- of drivers getting erroneous quotes for repairs with high-performance parts, such as for an AMG or Brabus for a Mercedes, and then receiving standard or stock components in their place.
Up in your grille
Willy Stroppe, the president of automotive engineering firm Bill Stroppe and Sons in Paramount, California, says he once looked at minor damage to the front of a Ford truck that eventually turned into a huge repair bill. AOL Autos: Ford trucks
"It looks like the front plastic grille got broken with a light hit, but when we got into it the housing behind the grille was cracked and broken all the way up. Replacing everything from the fenders forward, the headlight vessels, a new front end, it all adds up. In a 'lotta cases you gotta pull out the radiator. That's not something you can do in a couple hours."
He's seen similar problems on a Ford Explorer -- Stroppe works mainly with Fords -- and the pickup's repair bill topped $1200. "It's not like the old days when everything was steel," he adds. AOL Autos: Ford Explorer
He also says that car buyers should be aware of the practice he's seen plenty of in his nearly half-century in the car business -- that of a repair shop buying a car whose frame and shell are in good condition but whose underbody needs a lot of work, for example, on its suspension. Often, he says, a dishonest shop will get the car roadworthy with a shoddy repair job, and then sell it on to an unwary buyer, prompting a huge future repair bill when the repair work crumbles.
$150 cover up
Mark Essig, a writer in a small town in North Carolina, says he was astonished to be charged $150 by a local mechanic to replace a missing cover for the trunk-release switch in his ten-year-old Mercedes CLK. While expensive repair bills are not uncommon for upscale European marques, Essig says this one was the icing on a frosty $2,000 repair bill he'd expected to come in at much less. He also noted it came as an additional cost not included in the estimate. AOL Autos: Mercedes CLK
He says: "It was part of a $2000 repair bill that included valve cleaning and brake work, and I was so sick to my stomach that I couldn't quibble over $150. Best part was, I didn't ask him to do it."
Meanwhile, Porsche 944 owner Michael Russell, an AOL Autos friend, found out to his cost that buying a old-school German car could unexpectedly cost more than he bargained for. A $15 exhaust valve replacement cost him $3,500 once labor was taken into account.
Basically, he says, they had to rip out the engine to get to the valve, which had burned out, a common ailment in older performance vehicles. But without the repair, he says, he had no way of getting to work. AOL Autos: Porsche 944
I found this cost when I took my wife's 1995 Nissan 240SX S-ER to my local mechanic's last week to fix the air conditioning. I'd already taken it into the shop the week before, where they'd diagnosed a leaking gasket that had depressurized the system. So they duly fixed the gasket, re-filled the system with Freon coolant and pressurized it. Bill: $300. AOL Autos: Nissan
Not bad for an AC fix, I thought, until two days later the system again began blowing hot. So it was back into the shop, where they took a second look at it before telling me another seal had broken, this time in a hard-to-reach spot, meaning extra labor. Estimated cost: $800.
When I pointed out that the original fix was under warranty, my mechanic agreed but argued that a different component had malfunctioned and therefore the additional repair was not under warranty. Many more attempts at bargaining failed. Result: I'm $300 out of pocket, and my wife has a long, hot summer to look forward to (unless she nabs my car, which is likely).
Advice: Get a second opinion, and always assess general system integrity when replacing individual components on older-model cars.
Ken Lavacot, of online mechanics 2carpros.com, says that while a little steam coming out of your exhaust could seem like nothing, it could be a sign of some serious repair bills ahead.
He says: "Coolant is used to cool the engine during normal operation. If coolant is allowed to enter the combustion chamber, the engine will burn the coolant creating white smoke and steam."
He says a range of expensive solutions includes gasket replacement. "If the gasket that seals the intake manifold to the cylinder head fails it can allow coolant to enter the intake port and then the combustion chamber. To check for this condition the intake manifold will need to be removed."
In this case, getting to the gasket and reassembling the parts after its replacement is where most of your money will go.
If there is coolant in the combustion chamber and the gasket is OK, Lavacot says the engine must be taken apart.
He adds: "This can be tricky because it is difficult to tell which is causing the problem. For example: A repair shop has told you the cylinder head is cracked, and as they start disassembly they can discover it was the intake manifold gasket that has failed. It's up to the honesty of the repair shop to alert the customer the repair will be less.
Or the opposite can happen. A repair shop has told you your engine has a blown head gasket, once the disassembly is complete they inform you the head gasket is OK, and the cylinder has been pressure checked and is OK. This only leaves the engine block as the failure and must be replaced to repair the problem, and that can be costly."
My brother-in-law got a little more than he bargained for when he lent his Jaguar convertible to a family member to take to a wedding a couple years back. To his horror, the car was returned with a scratch in the back panel on the driver's side.
Usually, a good repair or bodywork shop can buff out a scratch at minimal cost, but the XK8's aluminum shell meant that a costly adhesive had to be used to fix the scratch and not allow further deterioration or warping of the car's monocoque shell. Cost: $1500 (or enough to suitably strain family relations).
His body shop guy told him he was lucky the scratch was not deeper or in another part of the car, or repairs could double or triple in cost, an increasingly common occurrence as more luxury carmakers including Audi, Mercedes and BMW harness the aluminum-shell technology (taking advantage of its increased strength and lighter weight). Advice? Get several estimates for the paintwork. And think twice about lending out your Jaguar.
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