I have to admit that I've always been skeptical of the unintended acceleration claims that have popped up since, when was that, the '80s?
Anyhow, it happened to me yesterday. I was doing some spirited driving on a twisty road. I had recently had the car tuned and had been in the high rpm range, staying in an area where I hadn't spent much time before. I caught up to a 280Z at a relatively short passing section before a right hander that would require light braking.
I was next to the other car at 6,500 when the pedal went to the floor. I depressed the clutch - the engine went to its 7100 rpm governor - put the car in neutral, and before I even got my hand off the shifter to reach for the key, the pedal returned to my foot and the engine went toward idle.
I slowed down but continued driving to where I could safely pull off the road. The car behaved normally even up toward the 4000 rpm range except that it dropped toward idle between shifts slower than normal. The pedal felt normal, it was free and there was no stickiness in how it felt. It traveled smoothly.
When I stopped to look things over, nothing was amiss. The car has a TWM induction system controlled by a Big Stuff 3 ECU. Apparently, there's a throttle return spring in each of the induction ports although I haven't seen them personally. The pedal has a return spring too. The return spring on the pedal was still attached and intact. I didn't look at the induction system since everything felt and sounded normal.
I got back into the car and started off slowly for home, operating conservatively as if I was in gas saving mode. When the engine reached 2000 rpm though, it made a sound like a belt was slipping and the engine immediately lost power, as if it had reached the governor. I lifted and when the engine dropped below 2000, the noise went away and the engine ran normally.
In playing with the anomaly and investigating it, I could get past the noise and power loss by accelerating through the early 2000 rpm range at perhaps 20% TPS. That's just an estimate as I sit here thinking about it. However, when the engine got back into that range, 2000 - 2200, the symptoms showed up again. I only accelerated past it twice.
As I drove home, the anomaly became less frequent and it eventually stopped all together. As it became less frequent, so did the slow-to-idle-between-shifts issue. On the way home, I stopped for coffee and the car sat for half an hour or so. The rest of the drive was perfectly normal.
Any ideas?
Anyhow, it happened to me yesterday. I was doing some spirited driving on a twisty road. I had recently had the car tuned and had been in the high rpm range, staying in an area where I hadn't spent much time before. I caught up to a 280Z at a relatively short passing section before a right hander that would require light braking.
I was next to the other car at 6,500 when the pedal went to the floor. I depressed the clutch - the engine went to its 7100 rpm governor - put the car in neutral, and before I even got my hand off the shifter to reach for the key, the pedal returned to my foot and the engine went toward idle.
I slowed down but continued driving to where I could safely pull off the road. The car behaved normally even up toward the 4000 rpm range except that it dropped toward idle between shifts slower than normal. The pedal felt normal, it was free and there was no stickiness in how it felt. It traveled smoothly.
When I stopped to look things over, nothing was amiss. The car has a TWM induction system controlled by a Big Stuff 3 ECU. Apparently, there's a throttle return spring in each of the induction ports although I haven't seen them personally. The pedal has a return spring too. The return spring on the pedal was still attached and intact. I didn't look at the induction system since everything felt and sounded normal.
I got back into the car and started off slowly for home, operating conservatively as if I was in gas saving mode. When the engine reached 2000 rpm though, it made a sound like a belt was slipping and the engine immediately lost power, as if it had reached the governor. I lifted and when the engine dropped below 2000, the noise went away and the engine ran normally.
In playing with the anomaly and investigating it, I could get past the noise and power loss by accelerating through the early 2000 rpm range at perhaps 20% TPS. That's just an estimate as I sit here thinking about it. However, when the engine got back into that range, 2000 - 2200, the symptoms showed up again. I only accelerated past it twice.
As I drove home, the anomaly became less frequent and it eventually stopped all together. As it became less frequent, so did the slow-to-idle-between-shifts issue. On the way home, I stopped for coffee and the car sat for half an hour or so. The rest of the drive was perfectly normal.
Any ideas?