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http://biz.yahoo.com/ap/080310/gm_investigation.html?.v=1

WASHINGTON (AP) -- The government is investigating whether 2008 Pontiac Solstice and Saturn Sky sports roadsters with turbo engines have enough braking power.
The National Highway Traffic Safety Administration says it has received 40 complaints alleging that drivers need to press down hard on the brakes to stop the vehicle after it has started. The problem has been occurring in driveways or parking lots.

NHTSA (NIT'-sa) says it is aware of one crash that may be linked to the case. The agency has opened a preliminary inquiry into the issue.

The investigation covers 20,000 of the 2008-model Pontiac Solstice and Saturn Sky vehicles with 2.0 liter turbo engines.

General Motors Corp. spokeswoman Carolyn Markey says the automaker is fully cooperating with the investigation.
 

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Are the brakes upgraded on the Redline and GXP?
 

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I am assuming that they are referring to a condition of lack of vacuum assist to the brake booster. Only thing I can think of at low RPM like that that wouldn't effect it at cruising speed.

Of course, one would think that they would press in the clutch along with the brake pedal.
But I digress.
 

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Brings back memories - I purchased a new 1981 Chevrolet Citation 4 door HB with the 2.5 litre 4-cylinder engine and automatic transmission.

At times, the brakes would not operate properly and the driver had to push harder than normal on the brake pedal to achieve proper stopping. The engine would surge with the a/c on and the idle would fluctuate considerably - I think that had a bearing on the problem.

The dealer service technician told me at the time that it was "normal" and "they all do that". I do remember that the NHTSA did several investigations on the "X-Body" cars for braking deficiencies.

Back to the future.............
 

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I am assuming that they are referring to a condition of lack of vacuum assist to the brake booster. Only thing I can think of at low RPM like that that wouldn't effect it at cruising speed.

Of course, one would think that they would press in the clutch along with the brake pedal.
But I digress.
You have lots of vacuum only when the throttle is pressed HARD do you have positive pressure. But the engine uses VVT and electric throttle to keep it more open more of the time. But anyway there should be a vacuum reservoir, plus reserve in the booster itself and lots of engine vacuum when braking.



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According to my grandfather, GM had a fantastic 327 back in the stone age, lots of power and torque but they ended up killing it because it couldn't make enough vacuum, needed a vacuum booster like on diesel trucks to make it work, which wasn't efficient...

Same problem?
 

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According to my grandfather, GM had a fantastic 327 back in the stone age, lots of power and torque but they ended up killing it because it couldn't make enough vacuum, needed a vacuum booster like on diesel trucks to make it work, which wasn't efficient...

Same problem?

you mean a hydraulic assisted booster...
 

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Turbo engines don't create as much vacuum, if any at all, compared to NA engines.
 

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According to my grandfather, GM had a fantastic 327 back in the stone age, lots of power and torque but they ended up killing it because it couldn't make enough vacuum, needed a vacuum booster like on diesel trucks to make it work, which wasn't efficient...

Same problem?
Well if that is the issue, would it not effect every car that is getting this engine (Cobalt SS, HHR SS, etc.)?
 

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This is not the kind of news GM needs for its performance roadsters!

But i cant wait for the Solstice Targa GXP!!!
 

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Are we talking about a braking problem after a cold start or a warm start? If only after a cold start, how cold was the air temp around the affected vehicles, including the one that crashed?
 

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From the wording it sounds like people w/the automatic are complaining that when they let off the brake while the car is in gear it moves.......what do they expect to happen?
 

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Well if that is the issue, would it not effect every car that is getting this engine (Cobalt SS, HHR SS, etc.)?
I'd suspect so, but keep in mind that is the GXP model and only the HHR SS would have that engine other than the Sky and Solstice, and it hasn't been around long enough for anyone to notice yet.

I bet it will be fixed by the time the Cobalt goes into production. That's assuming GM didn't already know and have it fixed for the HHR too.

It seems like a legit problem, if like was said by someone else that they didn't expect an auto car to move when you release the brake, what are the odds that all these morons only drive Sky's and Solstice's? lol

They also say it's only 2008 models, so maybe they changed suppliers for something and got screwed.... because unless that's the case, there were no mentioned changes in the GXP models over the years. Could have got faulty parts...who knows. Buts it seems like they are working on it.
 

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Turbo engines don't create as much vacuum, if any at all, compared to NA engines.
Not exactly true. When you're not in boost, you're in vacuum. At idle, under light acceleration and while cruising, you're not even the boost, so the car is probably going to pull between 10 and 15 in/Hg.

The speeds at which the above problems occur would not be related to the turbo, per se. This sounds like not enough vacuum to the power brake booster, though.
 

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http://biz.yahoo.com/ap/080310/gm_investigation.html?.v=1

WASHINGTON (AP) -- The government is investigating whether 2008 Pontiac Solstice and Saturn Sky sports roadsters with turbo engines have enough braking power.
The National Highway Traffic Safety Administration says it has received 40 complaints alleging that drivers need to press down hard on the brakes to stop the vehicle after it has started. The problem has been occurring in driveways or parking lots.

NHTSA (NIT'-sa) says it is aware of one crash that may be linked to the case. The agency has opened a preliminary inquiry into the issue.

The investigation covers 20,000 of the 2008-model Pontiac Solstice and Saturn Sky vehicles with 2.0 liter turbo engines.

General Motors Corp. spokeswoman Carolyn Markey says the automaker is fully cooperating with the investigation.
Funny, I noticed this both times I test drove two different Solstice GXPs. And both times, I was slowing into a parking space on the dealer lot. It didn't happen when I was driving at speed, just barely moving the car. I got the impression that the brakes were vacuum deprived.
 

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Most NA vehicles I have driven are way overboosted in the brake system, so maybe GM has reduced the vacum assistance slightly on these vehicles to improve brake pedal feel? If the drivers had just got out of a typical slush box maybe they were not expecting the change.

These are marketed as high performance vehicles after all and journos (who normally pick up on these things - esp on GM vehicles) don't seem to have mentioned it so far.
 

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According to my grandfather, GM had a fantastic 327 back in the stone age, lots of power and torque but they ended up killing it because it couldn't make enough vacuum, needed a vacuum booster like on diesel trucks to make it work, which wasn't efficient...

Same problem?
That would be false. Worked on and drove most of the iterations of the 327. vacuum was no different than other small blocks,hi output motors had less vacuum but not that much less. Aftermarket high lift cammed motors were something else though, regardless of displacement
Ed
 

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Most NA vehicles I have driven are way overboosted in the brake system, so maybe GM has reduced the vacum assistance slightly on these vehicles to improve brake pedal feel? If the drivers had just got out of a typical slush box maybe they were not expecting the change.

These are marketed as high performance vehicles after all and journos (who normally pick up on these things - esp on GM vehicles) don't seem to have mentioned it so far.
I agree, I imagine most of these folk are just used to overboosted brakes.

Maybe everyone should have to drive a car without power brakes in order to receive their driver's license. Problem would be finding cars that don't have power brakes nowadays.
 

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Brings back memories - I purchased a new 1981 Chevrolet Citation 4 door HB with the 2.5 litre 4-cylinder engine and automatic transmission.

At times, the brakes would not operate properly and the driver had to push harder than normal on the brake pedal to achieve proper stopping. The engine would surge with the a/c on and the idle would fluctuate considerably - I think that had a bearing on the problem.

The dealer service technician told me at the time that it was "normal" and "they all do that". I do remember that the NHTSA did several investigations on the "X-Body" cars for braking deficiencies.

Back to the future.............
Oh God, I remember that all too well....the brakes on my '82 Citation were a nightmare and I rear ended another car because of it. Of course, GM accepted no responsibility. Thr power steering pump also would stop intermittantly and would make driving less than pleasurable. On the bright side, one hell of alot of cargo space for a hatchback.
 

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I HAVE PERSONALLY HAD THIS HAPPEN. This is a real issue. This has happened to a customer of mines car and a few times when I drove lot cars. It happens when you start the car, put in gear (either transmission), drive and the first few times you brake it feels like you have no brakes and they make a wretching sound like when your rotors and pads are worn out. There needs to be a TSB to fix it.
 
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