Check engine light, reduced engine power
Thread Starter
6th Gear
Joined: Jun 2021
Posts: 6
Likes: 1
Check engine light, reduced engine power
Hi folks, I recently purchased a 2008 z06. It has been going into reduced engine power mode randomly when I drive it. I’ve had it happen in town and on the highway.
the first time it happened I complained to the dealer where I bought it. They towed it back, said it was throttle position codes, and that they probably got water in the connector when they detailed it. They said they cleaned out the harness, added some electrical grease and tested it.
the next day the light came back on. I put in a new head unit which cleared the codes but it’s happened twice since. I’ve given up on the dealer which is also an hour away. I bought a code reader and the codes are:
P1516 throttle actuator control module throttle actuator position performance
P2101 throttle actuator control motor circuit range / performance
P2135 throttle/pedal position sensor/switch a/b voltage correlation
I did some googling and the sensor at the throttle body does sound like a possible issue but if it’s been checked what else could this be? Battery is a year old and 12.25 volts when off so it should be good. I’m not sure what else to check.
And does anyone know a reputable shop in north Jersey (Essex county preferably) that could fix this?
thanks!
the first time it happened I complained to the dealer where I bought it. They towed it back, said it was throttle position codes, and that they probably got water in the connector when they detailed it. They said they cleaned out the harness, added some electrical grease and tested it.
the next day the light came back on. I put in a new head unit which cleared the codes but it’s happened twice since. I’ve given up on the dealer which is also an hour away. I bought a code reader and the codes are:
P1516 throttle actuator control module throttle actuator position performance
P2101 throttle actuator control motor circuit range / performance
P2135 throttle/pedal position sensor/switch a/b voltage correlation
I did some googling and the sensor at the throttle body does sound like a possible issue but if it’s been checked what else could this be? Battery is a year old and 12.25 volts when off so it should be good. I’m not sure what else to check.
And does anyone know a reputable shop in north Jersey (Essex county preferably) that could fix this?
thanks!
Safety Car
Joined: May 2006
Posts: 3,698
Likes: 493
From: Potomac MD
Also what can happen is you might need a new wiring harness for the TB - it is a pigtail with about 7 inches of wire. The TB wires are tiny and can get break in them and you don't see it as they are covered by the vinyl. Most breaks occur in the first few inches. Just look on line and you will see lots of TB wire repair kits so that gives you a clue you wont be the first guy this has happened too.
Thread Starter
6th Gear
Joined: Jun 2021
Posts: 6
Likes: 1
Also what can happen is you might need a new wiring harness for the TB - it is a pigtail with about 7 inches of wire. The TB wires are tiny and can get break in them and you don't see it as they are covered by the vinyl. Most breaks occur in the first few inches. Just look on line and you will see lots of TB wire repair kits so that gives you a clue you wont be the first guy this has happened too.
I hate throwing parts at it without knowing the root cause but at least the throttle body is cheap. Doesn't seem like I can buy just the sensor.
Instructor
Joined: Dec 2020
Posts: 105
Likes: 4
Did you try cleaning the throttle body first?
Our 05 was idling rough and the RPMs were dropping so low the car almost stalled when shifting it into neutral while driving, and the problem was solved in 20 minutes by simply cleaning the mass airflow sensor and the carbon build up in the throttle body, around the butterfly. That little bit of effort made it run like a new car and fixed rough cold starting issues.
Our 05 was idling rough and the RPMs were dropping so low the car almost stalled when shifting it into neutral while driving, and the problem was solved in 20 minutes by simply cleaning the mass airflow sensor and the carbon build up in the throttle body, around the butterfly. That little bit of effort made it run like a new car and fixed rough cold starting issues.
Thread Starter
6th Gear
Joined: Jun 2021
Posts: 6
Likes: 1
Did you try cleaning the throttle body first?
Our 05 was idling rough and the RPMs were dropping so low the car almost stalled when shifting it into neutral while driving, and the problem was solved in 20 minutes by simply cleaning the mass airflow sensor and the carbon build up in the throttle body, around the butterfly. That little bit of effort made it run like a new car and fixed rough cold starting issues.
Our 05 was idling rough and the RPMs were dropping so low the car almost stalled when shifting it into neutral while driving, and the problem was solved in 20 minutes by simply cleaning the mass airflow sensor and the carbon build up in the throttle body, around the butterfly. That little bit of effort made it run like a new car and fixed rough cold starting issues.
I also picked up one of the cheap silver blade knockoffs (trq brand) and I’ll try that next. Had no idea it would be so hard to find a throttle body for this car.
