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2000 Jeep Cherokee 4.7L V8: P0601, P0320, P0108 Codes - Engine Stalls, Black Smoke, Gas Smell & Check Engine Light

Model: Jeep Cherokee 2000 Fault Code: P0108 Posted: 2014-09-28 13:00

I own a 2000 Jeep Cherokee with a 4.7L V8 engine. About a year ago, while driving on the freeway, I heard a loud pop from the engine as I approached my destination. Shortly after, the check engine light illuminated, and I began noticing a strong gasoline smell along with black smoke coming from the exhaust. After taking it to a mechanic, the following diagnostic codes were returned: P0601 (PCM Internal Controller Failure), P0320 (No Crankshaft Position Reference Signal at PCM), and P0108 (MAP Sensor Voltage Too High). The vehicle now stalls unexpectedly, exhibits fluctuating MAF/MPR readings that rise and fall on their own, and shuts off when coming to a stop. Once restarted, it emits a noticeable gas odor—suggesting a possible fuel leak or sensor malfunction. I understand the codes but am unsure what causes the stalling and the smell of gasoline. Can someone clarify these symptoms and provide guidance on how to diagnose and fix them?

Related fault codes
P0108P0320P0601
Comments (5)
Anonymous 2014-09-28 14:36

This is a 4.7L V8 engine, not 4.0L. P0108 indicates the MAP sensor voltage is too high—this could mean the sensor isn't properly sensing vacuum or has a short to power. P0320 shows no crankshaft position reference signal at the PCM, which means the CKP (Crankshaft Position) sensor is likely faulty or has intermittent connectivity. P0601 points to an internal failure in the Powertrain Control Module (PCM). Two major issues: first, a vehicle should not run with a P0320 code—this suggests intermittent signal problems. Check the CKP sensor for corrosion, loose connections, or damage. The MAP sensor is also suspect—verify it's not shorted to voltage or misreading vacuum levels. Is the vehicle stock? Confirm and repair CKP and MAP issues before considering PCM replacement. After fixes, clear codes and perform a road test to verify improvement.

Anonymous 2014-09-28 14:59

If this is indeed a 4.7L V8 (common in later 2000 Jeep Cherokees), then the engine is not a 4.0L. The PCM showing multiple sensor faults while itself failing suggests it may be misreading data due to internal failure. In such cases, the PCM's diagnostics are unreliable—many sensors might appear faulty when they're actually functioning correctly. Should I prioritize fixing the CKP and MAP sensors before replacing the PCM? Or should I replace the PCM first? I've heard that a failed PCM can falsely trigger sensor errors even if the hardware is fine. The vehicle has aftermarket upgrades: a double DIN stereo, high-intensity discharge (HID) headlights, sound system with amplifiers and subwoofers—these are not stock components. Engine remains stock.

Anonymous 2014-09-28 15:17

Stay positive—first focus on diagnosing the CKP and MAP sensors. The vehicle cannot run without a valid crankshaft position signal (from CKP), so an intermittent issue is likely at the sensor or its wiring harness, possibly near the starter motor. For the MAP sensor, it's located on top of the intake manifold. Begin by inspecting connections for corrosion, tightness, and damage. Try cleaning and reseating both sensors. After addressing these components, clear the codes and perform a test drive to see if symptoms resolve. Before investing in a new PCM—which can cost hundreds of dollars—ensure that the underlying sensor issues are properly resolved. This approach avoids unnecessary expense while improving reliability. By the way, what does 'double DIN' mean? Are you referring to an aftermarket stereo with touch screen and Bluetooth features? What about HID lights—brighter headlights? And the sound system—amplifier and kickers for enhanced audio?

Anonymous 2014-09-28 15:32

Got it—I'll start by checking the CKP and MAP sensors. I didn't know where to begin, and I'm worried about spending a lot on a new PCM only to find that the real issue is elsewhere. Thanks for clarifying! A 'double DIN' stereo refers to a larger-than-standard car audio unit—like modern touch-screen systems with Bluetooth, navigation, Sirius radio, and app support. HID lights are brighter, more efficient headlights (e.g., blue or white). For sound, I have an amplifier and two kickers that boost bass and overall volume—so it's definitely not stock.

Anonymous 2014-09-28 20:18

When addressing the CKP and MAP sensor issues, avoid exposing a new PCM to known faults. A replacement PCM will still detect these problems and may trigger false or persistent error codes if the root cause isn't resolved first. This is critical—fixing the sensors before replacing the PCM ensures accurate diagnostics and long-term reliability.