Runaway Engine When Driving

[YoungReatta]

Hello, been a quiet reviewer and enjoyer of the ROJ and AACA forums. I bought a non running reatta several years ago running it as my summer driver for 3+ years after fixing it up myself andhave now encountered a niche issue. The engine in park idles perfect around 650rpm when warm and around 800rpm when cold. However, today i experienced something very concerning and unsafe making the car undriveable. When ever you selct a gear the engine rpm just climbs and climbs and runs away from me somewhere in the neighborhood of 3300rpm+. I thought it might be mechanical in the linkage but the throttle cable and the linkage looked perfect. The butterfly opened smoothly at idle and IAC works as intended on the reattas data screen. When in drive it idles fine until you hit the gas and then starts to runaway on me. Tps looks perfect numbers wise but yhe IAC just starts to climb to like 60-70 and its a brand new delco IAC as of 2 years ago. Making me think its not that.

 

Tried researching and couldn't find anything that made me feel confident. Little lost and dont know where to look and figured Id ask the forums... thanks again. 

[Ronnie]

Welcome to the forum!

5 minutes ago, YoungReatta said:

When in drive it idles fine until you hit the gas and then starts to runaway on me.

That sounds like a transmission problem or perhaps a bad axle. When the RPMs go high, with the transmission in drive, does the speedometer read any speed on it?

[Ronnie]

13 minutes ago, YoungReatta said:

When ever you selct a gear the engine rpm just climbs and climbs and runs away from me somewhere in the neighborhood of 3300rpm+.

Maybe I'm misunderstanding the problem. When you say it runs away from you is the car moving or just the RPMs going up like I was thinking in my last post?

[Ronnie]

Never mind. I see you are getting help on the AACA.