Tag Archives: Throttle

Questions and answers relating to engine throttle controls. Carbon in the throttle will cause hard stating and low or rough idle on your car or truck.


Ford f150 power loss at half throttle

Ive got a 1995 Ford F-150 4×4 with the 302 5 speed. All started with a few bucks when it was cold and the check engine light would come on then go off. Now the check engine light is steady on and it works ok at half throttle. But anymore than that it looses power completely. The truck is shut off only its not. If…

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After Replacing Oxygen Sensors And Throttle- Truck Has High Idle

I have a 2000 Ford F-150 4.2 ltr v6 2wd. It was throwing codes p0171 and p0174. I changed the upstream o2 sensors and the MAF. Took it back to Autozone to check the codes one more time and they said it was an IAC valve (idle air control) code so I replaced that. After I cleaned the throttle body, it started running at an…

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2002 Chevrolet Malibu Has A Very High Idle

2002 Chevy Malibu w/3.4L idles @3,000 rpm. The TPS, PCV, fuel filter, fuel pump assembly, and charcoal canister was replaced after vacuum hoses were repaired. What else could cause this problem? Well really the only thing that will do that would be a bad throttle position sensor, or a major vacuum leak. A stuck open idle air control valve can cause this, but it would…

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1996 Toyota Corolla Has A Low Idle

I have a 1996 Toyota Corolla 1600 cc which started to rev very low on start up to the point that it would cut out. A code reader showed a coolant temperature sensor code so i replaced it . Now when I start the car is does rev higher but not as high as i think it should and remembering it doing. After a period…

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Chevrolet S-10 Truck Starting Problems Answered

1994 Chevrolet S-10 4.3 tbi. I never get the signal to turn on the fuel pump or fire the injectors but if i poor gas in the intake once the truck starts it runs fine. Any ideas ? I have replaced the fuel pump relay oil pressure switch and computer. ProTech: If you’re not getting a signal for fuel, then you either have a faulty crank…

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2001 Chevrolet Cavalier Trac Off and Engine Light

Well my car is dead and it won’t start. The Trac off light came on and the check engine light and the battery light and the oil light came on and when I went to step on the gas pedal it wouldn’t increase speed. It is a 2001 Chevy Cavalier. Does the engine crank over when you turn the key? The engine tries to turn…

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1995 Buick Stalled and Won’t Start After Replacing Intake Manifold

Hi ,I’m new to the world of fuel injection and sensors such as a knock sensor. I have a 1995 Buick Century with a 3.4L Pontiac engine. I used the 3.1L intake manifold system and have been driving the car for several months now without any problems till 2 nights ago, I was doing nearly 10mph when the car died without any type of warning.…

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2007 GMC Sierra Burns Oil and Idle Problems

2007 GMC Sierra with 50k miles has started to use oil, could this be a PCV problem? There have been problems with oil consumption on those engines. Mainly a piston ring problem, but there is a service bulletin to attempt a correction before replacing pistons and rings, which is a big job. Do you have a number or date? Just a second and I will…

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Where Is The Coolant Temp Sensor Located?

Where is the Coolant temperature sensor located at on a 1999 Oldsmobile Silhouette? ProTech: It is located on the left side of the front cylinder head on the intake. ok if that is bad will it keep the cooling fans from coming on have replaced the Coolant temperature switch and all 3 relays and the still will not come on any ideas. it can cause…

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2004 Chevy Venture Accelerates On It’s Own

I have a 2004 Chevy venture van with a 3.4 that accelerates when it wants to. It happens when cold or hot, just starting or going down the road. I have changed the TPS and IAC and plugs for both of them. Found a bad vacuum line between Map and fuel pressure regulator and also one on the EGR and replaced both of them. I…

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2006 Chevy Malibu Will Crank But Not Start

My 2006 Chevy Malibu will crank up, but it will not engage/or turnover until i press the accelerator…once that happens it works out fine…until the next time i crank it up. ProTech: Can you give a bit more info? Crank up, engage, and turnover all mean the same thing so I’m a bit confused. Will it crank but not start? OK, i would attempt to…

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Knock In 2002 Chevy Malibu Engine

Why would a 2002 Chevrolet Malibu with a 3100 knock through the intake only when opening the throttle body. Protech: Hello, is the sound like an engine knock or valve train noise? .Or more like a backfire. Like metal hitting the inside of intake but only when giving it gas. its not a ping or backfire. OK, that is a valve train issue. You could…

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1998 Chevrolet Silverado Stalls When Hitting Brakes

When i apply the brake it kills the motor on my 1998 Chevy Silverado 5.7 liter .i just changed the gas tank,fuel pump, and,fuel filter. Truck runs great until you apply brake. Mechanic JK: Does your truck die out as soon as you touch the brake pedal, or does it die out as you coming to a stop and sitting at idle? Only when you…

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Chevrolet Camaro Engine Light And Lean Codes

So, today I had an older model Camaro, 2001, high mileage, and not very well maintained.  It came in with the check engine light on, and had codes stored for the fuel trim being lean. Specifically, a P0174 Fuel Trim Lean Bank 2 code. This was surprising as while watching the info on the Tech 2 scanner, both banks seemed equally lean. Usually, lean codes…

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