Q: P0123 code 1999 Jeep Wrangler

asked by on

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.

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.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. P0123 code 1999 Jeep Wrangler

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: My car starts, runs, and goes into gear but it won't move.

Hi there. Check the torque converter bolts and make sure that they are installed into the flex plate. The sound is the torque converter hitting the sides of the bell housing. It also could be the flex plate being broke...

Q: Clutch pedal goes to floor when pressed

With the symptoms you have described, the most likely cause is a leak in the clutch hydraulic system. If there is a leak on the system it causes air to enter. Since air is not able to be compressed the...

Q: when shifting gears release clutch feel like it's still engaged

This is a symptom of a slipping clutch disc. You should have a mechanic verify the clutch linkage is not binding and quote the replacement clutch.

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.