Q: P0123 code 1999 Jeep Wrangler

asked by on March 06, 2017

Jeep threw a p0123 code, so far we've replaced the ecu & throttle position sensor. It idles at normal 800 rpms but when coming to a stop it drops down real low & sometimes stalls out. We hooked a scanner up to it & says the throttle is at 100%

My car has 240000 miles.
My car has an automatic transmission.

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Hi there - this may seem like a wild shot, but I wonder if your torque converter lock-up clutch is failing to release as you coast down, and the engine is having to fight it? I would think you would sense that the engine is under load when this occurs, but perhaps it is only partially disengaging. You have certainly done the logical things diagnosing the throttle. For further diagnostic assistance, I recommend a stalling inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.

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