Runaway!

[89Firebird2.8]

Was driving around last night with my friends, and i popped it into neutral to coast down main street(if i get it up to 45 and pop it out of gear, it will go the rest of the way at 35, which is the speed limit). and all of a sudden, the engine just revved high. I pushed the clutch in as it reached 5,500 rpm, and it stopped. It did it another time later on too. What could be causing this? And why would pushing the clutch in stop it?

[89Firebird2.8]

I just read the codes
13
22
24
32
34

[CamaroRS92]

sounds like a malfunction with cruise control (if you have cc)

[muff34]

Originally Posted by 89Firebird2.8

I just read the codes
13
22
24
32
34

13 -oxygen sensor fault-signal too low/open left oxygen sensor circuit.(dual sensor models)

22 throttle position sensor-signal voltage is low
fuel cutoff relay circuit-open or shorted to ground

24 veh speed sensor -open or short circuit problems or park neutral wsitch circuit problem

32- Barometric pressure sensor circuit failure
EGR valve diagnostic switch -closed during engine start up or open when egr flow requested by ecm
electronic vacuum regulator valve error
evrv controls egr vacuum

34 maf sensorsignal voltage or frequency to low during engine cruise
MAP sensor signsal voltage is low during ignition on
pressure sensor circuit-signal voltage too high or low (carbureted engine)


Source -GM code reader manual

[89Firebird2.8]

Actually, I think those codes have been up for a while, been too lazy to clear them or fix the problems, as it wasn't affecting how the motor runs. I took off my intake and looked inside the throttle body. It was all gunked up. I took some carbeurator cleaner and cleaned the butterfly(or whatever they call it) and all around it while it idled. It seems to be running quite noticeably better now. I'll see if it tries to run away on me again. I also need to turn down my idle. It idles at about 1,500 RPM. I put it up that high for some reason ages ago that i can't remember now.

[muff34]

Originally Posted by 89Firebird2.8

Actually, I think those codes have been up for a while, been too lazy to clear them or fix the problems, as it wasn't affecting how the motor runs. I took off my intake and looked inside the throttle body. It was all gunked up. I took some carbeurator cleaner and cleaned the butterfly(or whatever they call it) and all around it while it idled. It seems to be running quite noticeably better now. I'll see if it tries to run away on me again. I also need to turn down my idle. It idles at about 1,500 RPM. I put it up that high for some reason ages ago that i can't remember now.

so why bother posting then if it something that you don`t want to be bothered fixing ???

[89Firebird2.8]

Well i'd thought for a second that those were the reason for it idling weird.

[wrightz28]

If all those were "malfunctioning" at the same time, the CEL would be on pronto. Multiple codes like that usually scream ground wire connector since the bullk of the sensors use the same one.