If you are experiencing problems with your Jeep stalling on you at random intervals then hopefully this article could assist with your troubleshooting. Does your vehicle stall when coming to a stop, or when driving very slowly? Does your Jeep only stall when you reverse? Let’s look into what could be the possible causes of these symptoms.
If your Jeep stalls randomly you need to inspect the following components:
- Crank Position Sensor
- Low Battery
- Oil Pump Drive Assembly
- Wiring Harness
- Ignition Switch Actuator Pin
- Fuel Pump
When troubleshooting a stalling issue, there are two main areas you want to investigate first, and those are, but not limited to:
- Fuel Supply
- Electrical Components
Most stalling problems can be narrowed down to these two areas. Now those are two very wide-ranging categories so we’ll break down the usual suspects that could cause your Jeep Wrangler to stall.
Table of Contents
Jeep Wrangler Randomly Dies
So you’re driving down the road and come to a stop when suddenly your Jeep stalls without any prior warning. Or you could be cruising at a very slow speed when this happens. Strangely, when driving on the highway, your Jeep appears to be going perfectly fine.
Most Jeep owners report, once this happens, the engine light appears, but no error code is kicked out. The vehicle restarts as if nothing happened and appears to be able to function 100% fine again. This is also completely random and not a phenomenon you can recreate, which always makes troubleshooting a lot more tricky.
Symptoms to look out for when stalling:
- Check engine light flickering
- No other warning symbols appear
- Gauges and instruments remain on
- Fuel Gauge returns to empty
- Cruise control cancels out
So now we know what the symptoms are, let’s look at some of the possible solutions to this weird stalling problem.
Jeep Wrangler Stalling Problems (SOLUTIONS)
If you are mechanically minded or a DIY type of person, then these checks and fixes are relatively easy to perform and can be carried out with no special tools.
So let’s start by looking at the most common reasons why Jeeps stall and work our way down.
Crank Position Sensor
Electrical gremlins are a real pain in the, “you know what”, to diagnose at times. These can cause sudden stalls and even the inability to restart the engine again.
A very common cause of sudden fails on Jeeps and many other modern vehicles is the CPS (Crank Position Sensor).
The purpose of the crank position sensor is to monitor the position and rotational speed of the crankshaft. The engine computer then takes this information to control the fuel injection and the ignition timing system. If the crank position sensor is bad, it can cause misfiring, poor engine performance, and stalling since the engine is robbed of spark, which it needs to function properly.
Take note not to use sub-standard electrical components when replacing them. When replacing electrical parts, use only genuine MOPAR parts for the best performance and functionality.
Bad CPS Symptoms include but are not limited to:
| 1 | Erratic engine behavior |
| 2 | Rough idle |
| 3 | Frequent stalling |
| 4 | Decrease in engine power |
| 5 | Increased fuel consumption |
| 6 | Slow/lethargic acceleration |
| 7 | Check Engine Light appears |
| 8 | Inability to start |
Let’s now look at another sneaky component that can cause unexpected stalling.
Ignition Switch Actuator Pin
There is a pin inside your ignition switch that can be responsible for engine stalling without prior warning. One of the parts inside the switch is a metal rod and a link that triggers and sends an electrical signal to your starter motor when cranking. It then retains the key securely and keeps the connection closed within the switch.
So if the ignition switch is not functioning properly, the connection between the ignition and fuel systems is cut off, which will cause the engine to stall. Depending on how bad the switch is, the engine might or might not start.
It’s always recommended not to add a bunch of unnecessary keys or any heavy key ring decorations on your ignition key, since the additional weight will prematurely wear out your ignition barrel, resulting in intermittent connection and stalling issues.
Removal and Repair Procedure:
- Remove the ignition switch from the steering
- Remove the ignition switch actuator pin assembly from the ignition lock cylinder housing.
- Install the new ignition switch actuator pin assembly into the ignition lock cylinder housing.
- Refit the ignition lock cylinder.
Next, let’s investigate the OPDA
OPDA (Oil Pump Drive Assembly)
A problematic OPDA was an issue on the 4.0 engine ranging in years models 1992 to 2006. The factory standard OPDA was designed with two bronze oil bushings, which were separated by an oil seal. The upper bushing is cut off from lubrication by that seal, resulting in premature failure. Over time, radial movement develops in the shaft. Eventually, the complete assembly and camshaft will fail.
You ignore a bad OPDA at your own peril since failure to replace this relatively inexpensive component will result in a lack of sufficient lubrication and eventually catastrophic engine failure. The repair is a DIY repair for any hands-on type of person without the need for any special tools.
This video demonstrates the replacement procedure perfectly.
Jeep Wrangler Stalls When Stopping
There are multiple reasons why a vehicle will stall intermittently and we’ve covered a few common causes of them so far. Now, let’s investigate which other components can cause the same stalling phenomenon when stopping.
Faulty or Weak Battery
A bad battery can cause all sorts of electrical gremlins. When the battery is weak, it has very low cranking power and amps. This can cause incorrect electrical signals, “confusing” the ECU, causing your Jeep to stall unexpectedly. A weak battery also means extra hard work for your alternator to try and charge the battery and keep the engine running. The additional load on your engine components can also cause an unexpected stall.
Wiring Harness
These faults are always difficult to troubleshoot. It’s also one of the last things we tend to check, at least I am guilty of that.
Electrical harnesses that are constantly exposed to heat are usually the first ones to perish quicker than the rest. Chaffing and moisture exposure can also cause shorts and electrical gremlins to develop over time. Always start inspecting the harnesses closest to your firewall that wrap around the valve cover. There are 2x bolts sticking up presses into the harness creating random shorts and misses. No code will appear either.
Fuel Pump
Signs of a Failing Fuel pump are, but are not limited to:
- Decrease in fuel efficiency
- Weak acceleration and power
- Spluttering
- Whining or loud humming sound from the rear near the fuel tank
A weak fuel pump with low-pressure results in your engine not getting the correct fuel-to-air mixture it needs to power the vehicle. Whining in the backseat.
Resources
Wrangler Wiring Harness Kit 07-18
Conclusion
We’ve identified a few common causes of Jeeps Wranglers stalling. Always take care to replace any electrical components with genuine MOPAR parts for the best results. Avoid cheap shop components which can send inaccurate electrical signals and strengths resulting in other problems down the line. A battery is often overlooked for strange stalling behavior so ensure your battery is still healthy and not more than 3 years old. Before replacing electrical components, do a thorough clean and spray all contact points with a good dielectric spray for good connection.