Autobog visits LaFontaine Toyota to find out how a recalled pedal is fixed – Click above to see the process step-by-step

Toyota has built up the most enviable reputation for quality and durability in the auto industry, but the once unassailable industry giant is now embroiled in two simultaneous recalls related to faulty accelerator pedals. The floormat pedal entrapment recall announced late last year is the company's largest ever involving over four million vehicles, but the sticking accelerator pedal recall announced on January 21st has hurt its reputation the most. The Japanese automaker announced earlier this week that it would address the more recent of the two recalls by installing a metal shim into the pedal assembly of each affected vehicle. Toyota claims this fix will reduce the amount of friction that could cause the pedal to stick in certain situations.

We wanted to know exactly how the recall fix would be performed on the 2.3 million vehicles affected, so as soon as the shims began arriving at Detroit-area Toyota dealers on Wednesday, we and our PICs (that's Partners In Crime) from AOL Autos made arrangements to visit LaFontaine Toyota in Dearborn. Owner Mike LaFontaine Jr. and fixed operations director Todd McCallum agreed to let us check out the repair process and answer our questions. Read on after the jump to learn all about it or see the process step-by-step in our gallery.

Related GalleryHow Toyota dealers will repair sticky accelerator pedals

Photos by Sam Abuelsamid / Copyright ©2010 Weblogs, Inc.

When we walked into the service department at LaFontaine Toyota, it was filled with brand new Corollas. McCallum explained that after receiving the first batch of shims on Wednesday, the technicians immediately began pulling cars off the lot to start executing the repair process. The plan was to spend the first day practicing the repair on cars in stock before starting to repair customer cars on Thursday. LaFontaine Toyota has about 200 recalled cars on the lot and their technicians would be working late into the night to get as many of them repaired as possible.

The first deliveries of shims are for Corollas only, with subsequent shipments for other affected models arriving over the next several days. McCallum expects to receive about 300 shims a day at first, with the number gradually increasing as production ramps up. Initially the process will take up to 45 minutes per car, but McCallum expects that time to shrink as the technicians get more practice.

Master Toyota technician Doug Kropp took us through a complete repair on one of the Corollas in the shop. The first step is to examine the pedal assembly to determine if it's one of the potentially problematic units. North American market cars have pedals from one of two suppliers, CTS and Denso, but only CTS units are subject to the recall. Among the CTS-made pedals, only units manufactured within a certain date range are known to have problems and each pedal assembly has a code that indicates its manufacturing date. Fortunately for us, the Corolla that Kropp was working on had a pedal that needed the fix.

Kropp first removed the two bolts that hold the pedal assembly on the firewall, followed next by the wire harness connector for the position sensor. Like almost all modern cars, the accelerator pedal is not physically connected to the throttle. Instead, a position sensor on the pedal arm detects how far the driver has pushed down. The sensor then sends an electrical signal to the engine management system, which also factors in signals from the traction/stability control, emissions sensors and other sensors to determine how far to open the throttle. Because there's no physical connection between the pedal and the throttle, the assembly has a mechanism that simulates the force feedback you would otherwise get from the throttle itself.

There are two grooved metal parts that rub against each other to provide some resistance in the pedal travel, as well as a return spring that pushes the pedal back up when it is released. This is what Toyota has identified as the source of the problem. On some vehicles and in certain situations, these friction shoes are interfering too much, exceeding the return spring force and potentially holding the pedal in place. The fix Toyota has developed involves installing a steel shim (Toyota calls it a reinforcing bar, although it doesn't seem to actually reinforce anything) between the spring stopper and housing.

Because all manufactured parts have tolerances, the amount of adjustment required varies from car to car. Kropp and other technicians use a feeler gauge (above) to measure the gap between the spring stopper and the pedal assembly housing. Based on that measurement, they select a shim to insert into the housing with one of seven thicknesses that range from 1.4–2.9 millimeters. Using the correct shim thickness ensures that the pedal doesn't end up with too little friction. According to both Kropp and McCallum, the updated pedals don't have any significant difference in feel before and after the procedure. If you own one of the recalled models and have this repair done, let us know if you notice any difference.

After inserting the shim, the friction shoe is pried up so that the plate can slide all the way in. Once the shim is properly seated, the pedal is pumped several times on the workbench to make sure nothing is hanging up. If it feels okay, the pedal is reinstalled in the car. Kropp also plugs in a diagnostic computer before the car leaves the shop to run some diagnostic checks that ensure the position sensor hasn't been damaged during the repair process. He then pumps the gas pedal through its full travel several times to check the voltage coming from the sensor. Once that process is completed successfully, the car is released back to its owner.

The pedal shim installation addresses Toyota's sticking accelerator pedal recall, but LaFontaine Toyota and other dealers will also begin reshaping gas pedals on more than four million Toyota and Lexus vehicles in the next several days. This repair addresses Toyota's other major recall involving pedal entrapment via defective floormats, and McCallum explained this process to us as well.

Toyota is providing templates to dealers for each of the affected models. With the pedal assembly out of the car, the appropriate template is used to scribe the back of the pedal. A reciprocating saw is then used to remove excess material from the pedal that could catch a floormat, and the edge of the pedal is then re-finished with a router. Once the pedal is installed back in the car, the engine management software is also updated before the car is released. We believe the software update incorporates the brake override functionality that will turn off the engine or close the throttle if the brake and accelerator pedals are applied at the same time. McCallum expects the pedal reshaping process to take about two hours at first, eventually coming down to about 90 minutes as service technicians get better at it.

Speaking of those technicians, it looks like there will be extra jobs for them during the next year as dealers work to correct millions of vehicles. McCallum told us that LaFontaine Toyota expects to hire an undetermined number of technicians and will extend service hours well into the night and on weekends to get through the repairs as soon as possible. Nonetheless, he expects it will take at least until the end of 2010 to complete the bulk of the repairs. Owner Mike LaFontaine Jr. also acknowledged that the recalls have affected sales, although he declined to get specific.

At least in the near term, both recalls will be a boon to Toyota service departments. As with all warranty work, Toyota is paying dealers for the work being done, and in the case of the shim repair, McCallum expects about $200 per car. This dealership expects to be repairing thousands of recalled customer cars over the next 12 months, not to mention a large number of fleet cars. Local Hertz rental outlets in the area have about 1,000 cars sitting idle right now that LaFontaine Toyota will eventually correct. It remains to be seen, however, whether all this extra service revenue for dealers will make up for what they've lost in sales. And if either of these two recalls are expanded or new recalls added for other problems like braking issues with the Prius, things will only get worse.

Related GalleryHow Toyota dealers will repair sticky accelerator pedals

Photos by Sam Abuelsamid / Copyright ©2010 Weblogs, Inc.