What are the most common Jeep Wrangler problems?

According to Au7o's research across NHTSA recalls, manufacturer TSBs, and owner forum reports, the 1999-1999 Jeep Wrangler has 1 documented issues. The most frequently reported are: 4.0L Crankshaft Position Sensor Thermal Failure — Random Stalling & Hot No-Start. Of these, 1 is rated critical and should be addressed promptly.

Is the Jeep Wrangler reliable?

The 1999-1999 Jeep Wrangler has 1 known issues compiled from NHTSA recalls, manufacturer TSBs, and owner forum reports. 1 issue is rated critical: 4.0L Crankshaft Position Sensor Thermal Failure — Random Stalling & Hot No-Start. Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.

How much does it cost to fix common Jeep Wrangler problems?

Repair costs for known Jeep Wrangler issues range from $60 to $250, depending on the specific problem and whether you choose DIY or professional repair. The most critical issue, 4.0L Crankshaft Position Sensor Thermal Failure — Random Stalling & Hot No-Start, typically costs $60-$250 to repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.

1999 Jeep Wrangler Problems: 1 Issue Every Owner Should Know

1999 Jeep Wrangler Problems: 1 Issue Every Owner Should Know | Au7o

All 1 Known Issues

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On the 1997-2006 Jeep Wrangler, the crankshaft position sensor (CPS) on the 4.0L (and 2.5L) inline engines mounts on the transmission bellhousing and is exposed to severe heat soak. As it ages it develops intermittent thermal failure: the engine stalls without warning once hot, then refuses to restart until it cools, after which it runs fine again — a maddening, hard-to-replicate fault. Frequently the CPS fails with NO check-engine light and NO stored code, so it is commonly misdiagnosed. It is a top-searched TJ/early-Wrangler stalling complaint and a roadside-safety concern because the stall is sudden.

This issue also affects: Chrysler LeBaron, Dodge Intrepid

Common Symptoms

Engine stalls suddenly while driving, especially when hot
Will not restart until the engine cools, then runs normally
Cranks but no start when hot
Often no check-engine light and no stored DTC
Intermittent stumble/backfire
Hard starting in rainy/humid weather

How to Fix

When the engine stalls hot and won't restart, unplugging and reconnecting the CPS connector (near the back of the intake) often resets the PCM and the engine fires — a strong indicator the CPS is failing. Replace the crankshaft position sensor with a Mopar or NTK/NGK unit (Mopar 56027866AE for many 4.0L applications; 4727451AA covers 2003-2011 TJ/JK 3.8L & 4.0L). Avoid bargain aftermarket sensors — out-of-tolerance units cause repeat no-starts. No relearn required; verify with a hot road test.

What you need to fix it

The exact parts — OEM, plus what owners actually use. Skip the internet hunt.

Crankshaft Position Sensor — 4.0L/2.5L, Manual Transmission (1997-2004 TJ Wrangler)
OEM56027865ABOwners use56041819AA, 56041820AA, 56027867AB$25–$80
Canonical era-correct CPS for the 1997-2004 TJ Wrangler 4.0L (and 2.5L) MANUAL-transmission engines — the primary fix part for the stall/hot-no-start fault. Mounts on the bellhousing and is exposed to the heat soak described. Manual-trans sensor has TWO mounting bolt holes (vs one for automatic), so
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Crankshaft Position Sensor Package — 4.0L, Automatic Transmission (1997/98-2002 TJ Wrangler)
OEM4897321AAOwners use4897321AB, 4897189AA, 56027868AC$35–$90
Era-correct CPS for the AUTOMATIC-transmission 4.0L TJ Wrangler, roughly 1997/98-2002 (also fits 98-04 Grand Cherokee 4.0L auto). The automatic sensor has ONE mounting bolt hole and a different harness/length than the manual unit, so it must be matched to transmission type. Mopar lists 4897321AA sup
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Crankshaft Position Sensor — 3.8L/4.0L, 2003-2011 TJ & JK (covers 2003-2006 of this issue's era)
OEM4727451AAOwners use04727451AA, Crown 4727451AA, Mopar 68407888AA$30–$85
Cited in the FIX text and verified. Fits 2003-2011 Jeep Wrangler TJ (2003-2006) & JK (2007+) with 3.8L & 4.0L gas engines — so it is the era-correct CPS for the 2003-2006 tail of this 1997-2006 issue window (2004 TJ auto confirmed: passenger side of bellhousing behind starter). For 1997-2002 TJ use
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Crankshaft Position Sensor — 4.0L (Cherokee XJ-family number cited in PROBLEM/FIX)
OEM56027866AEOwners use56027866AC, 56027865AB, Crown 56027866AE$35–$85
Captured because the FIX text names it explicitly. Verified as a genuine Mopar 4.0L CPS, but per Mopar/Quadratec/Crown listings it is cataloged primarily for the 1997-2001 Jeep Cherokee XJ 4.0L, NOT the TJ Wrangler. It shares the 56027865/866 family lineage so it appears in TJ aftermarket cross-list
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Part links may earn au7o a commission. Confirm fitment by VIN before buying.

Typical repair cost:$60 - $250

Research This Issue

0+ owners have reported this issue

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Community Reported

Medium ConfidenceVerified0 reportsLast reported by owners Invalid DateReviewed Jun 2026

⚠️NHTSA Recalls10 recalls

POWER TRAIN:CLUTCH ASSEMBLY:PEDAL/HAND LEVER(MOTORCYCLE)

Chrysler (FCA US LLC) is recalling certain model year 2006 Dodge Viper and Jeep Wrangler and Liberty vehicles manufactured July 1, 2005, to July 31, 2006. In the affected vehicles, the springs within the clutch pedal position switch that prevents the vehicle from starting unless the clutch pedal is pushed down may break. As a result, the vehicle may not be started when the clutch pedal is pushed down or the engine may crank and start without the clutch pedal being pushed down causing the vehicle to unexpectedly lurch.

Campaign #15V22200015/04/2015

POWER TRAIN:CLUTCH ASSEMBLY

ON CERTAIN SPORT UTILITY VEHICLES EQUIPPED WITH 6 SPEED MANUAL TRANSMISSIONS, THE HYDRAULIC CLUTCH MASTER CYLINDER LINKAGE ROD MAY BREAK. THIS MAY NOT ALLOW DISENGAGEMENT OF THE CLUTCH WHEN THE PEDAL IS DEPRESSED.

Campaign #06V14700003/05/2006

POWER TRAIN:AUTOMATIC TRANSMISSION

ON CERTAIN PICKUP TRUCKS, SPORT UTILITY AND PASSENGER VEHICLES EQUIPPED WITH 42RLE AUTOMATIC TRANSMISSIONS, THE CUP PLUG THAT RETAINS THE PARK PAWL ANCHOR SHAFT MAY BE IMPROPERLY INSTALLED. IF THE SHAFT MOVES OUT OF POSITION, THE VEHICLE MAY NOT BE ABLE TO ACHIEVE 'PARK' POSITION.

Campaign #05V46000006/10/2005

SERVICE BRAKES, HYDRAULIC

CERTAIN AFTERMARKET BRAKE HYDRAULIC MASTER CYLINDERS SOLD AS REPLACEMENT BRAKE CYLINDERS FOR CERTAIN FORD, DAIMLERCHRYSLER, AND JEEP PASSENGER VEHICLES. THESE BRAKE CYLINDERS WERE SOLD UNDER THE BRAND NAMES OF NAPA, RAYBESTOS, AIMCO, AC DELCO, CARQUEST, BENDIX, AND WAGNER. ONLY PRODUCTS THAT WERE MANUFACTURED FROM JULY 27, 2005 THROUGH JANUARY 17, 2006 (DATE CODES 0529 THROUGH 0602) ARE SUBJECT TO THIS RECALL. WHEN SUBJECT TO VERY COLD TEMPERATURES, AN INTERNAL SEAL IN THE MASTER CYLINDER COULD LOSE FLEXIBILITY AND MAY CAUSE BRAKE FLUID TO LEAK.

Campaign #06E02200013/03/2006

FUEL SYSTEM, GASOLINE:DELIVERY:FUEL PUMP

CERTAIN AFTERMARKET AIRTEX ELECTRIC FUEL PUMPS INSTALLED FOR USE AS REPLACEMENT EQUIPMENT FOR CERTAIN 1997-2004 JEEP WRANGLER; 1997-2001 JEEP CHEROKEE; 1997-2004 JEEP GRAND CHEROKEE; AND 2000-2003 DODGE DAKOTA VEHICLES. THE PLASTIC ELECTRICAL GROMMET CONNECTORS AT THE TOP OF THE FUEL PUMP MODULE ARE NOT COMPATIBLE WITH AUTOMOTIVE FUELS AND MAY DEGRADE CAUSING A POTENTIAL LEAK PATH FOR FUEL.

Campaign #06E01100001/02/2006

+ 5 more recalls. Check all on NHTSA.gov

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1999 Jeep Wrangler Problems: 1 Issue Every Owner Should Know

All 1 Known Issues

1997-2006 Jeep Wrangler: 4.0L Crankshaft Position Sensor Thermal Failure — Random Stalling & Hot No-Start#