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General Motors Co. plans to bring back mild hybrids next year, said Larry Nitz, GM executive director of hybrid and electric powertrain engineering.

GM discontinued mild hybrids after 2009 when the closing of Saturn left the carmaker with the technology on just one vehicle, the Chevrolet Malibu sedan, Nitz said. It had been available on the Saturn Vue crossover and Saturn Aura sedan as well.

Nitz, who spoke on the sidelines of the seminars here yesterday, said a new, more powerful system will be available in the third quarter of 2011 on at least one mid-sized sedan in North America and one in China.

He declined to name the vehicles, but he said the first-generation mild hybrid system was available in China on the Buick LaCrosse. He wouldn’t discuss the price of the option.

Unlike a full hybrid system, a mild hybrid system cannot propel a vehicle on electric power alone. It acts as a stop-start system, shutting off the gasoline engine when the car stops and then using the batteries to restart the engine when the accelerator is pressed again.

The motor also provides a boost during acceleration.

Nitz also said GM intends to make some of its own electric motors for hybrids instead of buying them all from suppliers.

He said the first GM-made electric motors will be produced in its White Marsh powertrain plant near Baltimore. He said they will be used on the next-generation Two-Mode hybrid technology, which will be an option on future pickups and SUVs.

Nitz called electric motors a core powertrain competency that GM must design and fully understand so it can integrate them into hybrids and plug-in electrics for peak fuel economy and performance.

He declined to reveal when the next-generation Two-Mode hybrids would be introduced. With a Two-Mode, a driver benefits at highway speeds from the electric motor, not just predominantly at starts and stops.

Nitz said GM will reintroduce mild hybrids on its mid-sized sedans with improved technology. They will offer about 20 percent better fuel economy than gasoline engines, he said.

Nitz said the electric motor is improved and the electronics and controllers are fully integrated with the conventional gasoline engine. The system will be wedded to GM’s Ecotech engine and a six-speed transmission capable of maximizing performance and fuel savings, he said.

When the mild hybrid was introduced in the Saturn Vue in 2006, it was bolted onto a four-cylinder engine and four-speed transmission not designed for regenerative braking. That mild hybrid produced a 15 percent improvement in fuel economy.

WASHINGTON – General Motors Corp. is recalling 1.5 million vehicles because of potential engine fires.

GM says there have been no reports of any fires or injuries.

Some of the recalled vehicles are no longer in production. The recall includes the 1998-1999 Oldsmobile Intrigue, the 1997-2003 Pontiac Grand Prix, 1997-2003 Buick Regal, and the 1998-2003 Chevrolet Lumina, Monte Carlo and Impala.

It involves vehicles with a 3.8-liter V6 engine. The government says drops of oil could fall into the exhaust system and cause a fire in the engine.

GM spokesman Kerry Christopher says it was a precautionary measure for consumers.

Question:

I have a 1992 GMC Sierra with a 5.7 liter engine that started acting up while driving down the interstate. It was running fine, and all of a sudden began sputtering and “popping”, and losing power. I was down to around 1/4 tank of gas, so I stopped and filled the tank. I thought it might be bad gas (water), so I went to a parts house and bought some “Heet” and some Chemtool brand fuel system cleaner and added it to the tank. It has done “some good” at driving speed, but still “chugs” when idling. I also changed the spark plugs, which did not make much difference. Can you give me some hints as to what the problem may be? My next step is to pull and check the distributor cap and rotor for damage, carbon, etc.
 

Answer:

There are so many different things that can cause this unfortunate situation, but eliminating some of them may help you narrow it down.

Checking the distributor cap for corrosion/burnt etc is good place to start.

Then test fuel pressure. Needs to be around 16 psi for TBI. Make sure it does not drop when accelerating. If not, replace the fuel pump and filter.

Then I would check, replace the ignition module (not expensive) as they tend to fail/break down often.

On a rare occasion the coil can start to break down and cause the same thing. Call around on this one and you can pick one up for around $16.00.

Worse case scenario, it could be a clogged converter and they are expensive for this model vehicle because of its size. You can test the back pressure with a gauge that screws into the O2 Sensor port and you should see no more than 1.5 psi

I have a 1994 Chevy s-10 and my battery light came on. Does this mean I need a new battery and how do I know if my alternator is bad?

Answer:

The battery is most likely fine. The battery light comes on to let you know it is no longer being charged. This is generally an indication of a failing alternator.

Testing : Using a multi-meter set to DC volts, connect the positive and negative leads to the same on the battery with the car’s engine running. You should see from 13.2 – 14.7 volts. If you see less than this and confirm it is the same when the engine is running or not, then you know the alternator is not charging.

Complete Alternator Troubleshooting