Update, April 24, 2006: General Motors has been slapped with a class action lawsuit in Canada. The suit comes after this CTV Whistleblower report that revealed problems with a small engine part in millions of GM vehicles. The lawsuit alleges GM is at fault for the failure of intake manifold gaskets in several of its vehicles.

It's a simple component buried deep under the hood -- in some one million General Motors vehicles sold in Canada alone. It has the potential to cause huge headaches though, for the GM vehicle owners.

It's an intake manifold gasket, put in at the GM factories, in some makes and models between 1995 and 2003. According to GM's own internal service bulletin, the part can "degrade" -- causing coolant to leak -- sometimes into the engine. Several vehicle repair mechanics told CTV that in the worst case scenario, the coolant mixes with engine oil -- making the oil ineffective -- and damaging the engine.

They say in extreme cases, the engines overheat and seize completely -- which means the vehicles need complete engine replacements. Some GM customers have been hit with repair bills of up to $5000 -- after their warranties have expired.

"I started to cry," said Ontario resident Lisa Slatter, whose 2002 GM Montana needs at least $1700 worth of repairs. "I cried and I cried because I thought I don't know how I'm going to pay for this."

Slatter's problems started when her vehicle had less than 100,000 kilometres on the odometer. It was leaking coolant, she said, and her warning light was on. An independent mechanic diagnosed a leaking intake manifold gasket -- and told her she should get it replaced.

Eventually, her GM Montana broke down completely. Now, she needs a new head gasket -- a significant repair.

"I didn't know (how serious that problem was) until my thermostat was over in the red," Slatter said. "It totally overheated. Because the coolant was gone."

"This is absolutely not normal wear and tear," said Kirk Robinson, an independent mechanic who worked as a GM service technician several years ago. He also hosts a call-in cable TV show in Toronto, called "Auto Talk".

Robinson agrees with several other mechanics, who told CTV they see and hear from GM customers with the same problem almost every day. Kirk told us he does repairs associated with GM intake manifold gaskets at least once a week -- and says it's the number one complaint he hears during his call-in show.

"It's very well known in our industry that this is a fault," he said. "It's definitely a manufacturing defect."

It turns out that GM has known about the problem for years. CTV obtained copies of four GM internal service bulletins -- from 2001 to 2004 -- warning General Motors dealers about the potential problem. For example, in 2001, GM wrote:

"Some owners may comment on excessive engine coolant consumption, or an engine coolant leak near or under the throttle body area of the upper intake manifold." "Upper intake manifold composite material may degrade...and could result in an internal or external coolant leak."

GM's service bulletins list several vehicles potentially affected -- 23 makes and models manufactured between 1995 and 2003. Since then, GM has come out with a new, improved intake manifold gasket. Still, mechanics say, the old part continues to break down in vehicles that haven't had it replaced.

Robinson, for one, thinks GM should have called all the potentially affected vehicles in for full repairs, when they first identified the problem.

"I think they should have brought (the affected vehicles) back and fixed it a lot sooner," he said.

"I think this is the biggest problem that I've ever seen with automobile manufacturers," said Phil Edmonston, who writes the consumer car guide Lemon Aid. "I really believe it's the biggest problem GM has ever had."

There's an on-line consumer petition -- with 11,000 signatures from GM customers -- calling for a voluntary "goodwill" recall by GM. In Canada, The Automobile Protection Association has logged 800 complaints. There are class-action lawsuits brewing in the U.S., where Edmonston now lives.

"The way to fight is just simply send a registered letter or an e-mail (to GM)," Edmonston told CTV, during an interview in West Palm Beach, Florida. "If your vehicle is not reasonably durable and has a mechanical defect, any judge on any bench -- small claims up to the Supreme Court of Canada -- can make that company pay."

Edmonston said he knows of several cases where GM has paid for intake manifold gasket repairs -- beyond the warranty period -- when customers have made a big fuss. He believes GM should now cover all related repairs, on all its affected vehicles.

CTV asked General Motors several times for an on-camera interview. The company sent a statement instead, which says, in part:

"An intake manifold gasket concern can arise from a variety of causes. It is for this reason that any concern a customer may have beyond the warranty period is handled on a case by case basis," wrote Stew Low, director of communications for GM Canada.

He also indicated there will be no voluntary recall of affected vehicles.

"GM does not plan to issue any type of goodwill action regarding the intake manifold gasket situation."

GM vehicles potentially affected (source: GM Technical Service Bulletins):

• 1995-1997 Buick Riviera
• 1995-1998/2000-2003 Buick LeSabre
• 1995-1998/2000-2003 Buick Park Avenue
• 1996-1998/2000-2003 Buick Regal
• 2000-2003 Buck Century
• 2002-2003 Buick Rendezvous
• 1996/1998-2001 Chevrolet Lumina
• 1998-2003 Chevrolet Monte Carlo
• 1997-2003 Chevrolet Venture
• 1999-2003 Chevrolet Malibu
• 2000-2003 Chevrolet Impala
• 1995-1998 Oldsmobile Ninety Eight
• 1995-1998 Oldsmobile Eighty Eight
• 1998 Oldsmobile Intrigue
• 1996-2003 Oldsmobile Silhouette
• 1999 Oldsmobile Cutlass
• 1999-2003 Oldsmobile Alero
• 1995-1998/2000-2003 Pontiac Bonneville
• 1997-1998/2000-2003 Pontiac Grand Prix
• 1996-1999 Pontiac Trans Sport
• 1999-2003 Pontiac Grand Am
• 1999-2003 Pontiac Montana
• 2001-2003 Pontiac Aztec

General Motors Canada encourages any of their customers to contact their Customer Communications Centre at 1-800-263-3777 if they have questions regarding their vehicle or service needs.

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