1991 Isuzu Trooper Problems

What owners report

Owners of the 1991 Isuzu Trooper most often describe transmissions that slip or shift roughly, and fires that started after fluid or oil leaks under the hood. Stuck accelerator pedals and tire tread separations at highway speed form other groups, while lug nut, seat belt, and electrical complaints appear in smaller groups. Most reports were filed in the late 1990s and early 2000s, the listed recalls concern transmission oil overfill and an oil cooler hose near the exhaust manifold, and some complaints say the vehicle was not included in a recall.

1. 1
   Transmission and drivetrain

   Transmission slipping, rough shifts, or rollaway

   • 10 complaints (18%)
   • typically at 8.8 yrs old
   • 5 mention a crash, fire or injury
   • filed 1995–2004

   Owners describe transmissions that shift roughly, slip, or fail again after repairs, sometimes with smoke before a fire. Some describe sudden acceleration when shifting from a lower to a higher gear, and a driver describes the vehicle rolling backward and crashing after it was left in what was thought to be park. Some say repeat repairs were only partly covered, that the manufacturer declined responsibility, or that a transmission recall did not include the vehicle by its VIN. None of these reports list mileage, and they were filed between 1999 and 2004; some describe rough shifting that dated from when the vehicle was new.

   What to check: Ask whether the transmission has been inspected for slipping, whether the fluid level and condition were checked, and for records of any repairs. On a test drive, confirm that the shifts are smooth in each gear and that the vehicle holds firmly in park.

   2 excerpts from owner complaints in NHTSA records

   “I have had a history (documented) of electrical/transmission problems with my 1991 Isuzu Trooper. On 11/95, a faulty computer control panel caused my transmission to fail. I had a week left on my powertrain warranty. Took the vehicle to Isuzu santa monica. They replaced the computer panel under warranty on 11/95. 15 months later, my transmission was failing again. Same symptoms. This time, I spent $2,000 to have it repaired. Isuzu refused to take responsibility. …”

   NHTSA complaint #707676, filed 1999-06

   “The transmission has been shifting rough since the vehicle was purchased new in 1991. The first incident was covered under warranty and some minor repairs/adjustments were made by the dealer. The second incident required more extensive repairs to the transmission and I was required to pay a portion of the repairs since the warranty had expired by some 2-3k miles. Upon the third incident with the drive train, I requested someone from the manufacturer to investigate. …”

   NHTSA complaint #711963, filed 1999-09
2. 2
   Engine cooling

   Under-hood or underbody fires after fluid leaks

   • 16 complaints (28%)
   • typically at 7.9 yrs old
   • 15 mention a crash, fire or injury
   • filed 1995–2003

   Owners describe fires after fluid leaked from the transmission or oil leaked from the engine, with smoke noticed first and flames spreading through the engine compartment. Some fires started while the vehicle was being driven on a highway or near a toll, and others started when the vehicle was stopped at a light. Some reports describe the vehicle as a total loss, and some record the fire cause as unknown. Mileage is not listed for these reports, and they were filed between 1996 and 2003; some describe the fire starting at highway speed.

   Recall 90V167000Recall 90V166000

   What to check: Ask whether the transmission oil level was checked and whether the recall repair for transmission oil or the oil cooler hose has been completed. Look under the hood for oil or transmission fluid residue, and for any hose that touches the exhaust manifold.

   2 excerpts from owner complaints in NHTSA records

   “The Trooper had an oil leak and the engine went on fire. My car is totaled. I have been researching and see a problem with this model and year. Help! I want Isuzu to pay for my lose even if I was the second owner or bob ciasulli used cars for selling me this car which had a recall on and put myself and my 5 year old son in danger.”

   NHTSA complaint #720987, filed 2000-04

   “I just exited the hollywood freeway when suddenly without warning the 1991 Isuzu Trooper caught on fire. I was able to get to the side of the road, and get out.the fire appeared to be underneath the truck with gas or some other liquid pouring out. The passenger side front tire melted and exploded, then there was a second explosion. All the parts of the engine, battery etc. Were in flames. Two fire trucks and police cars were dipatched. It was a very big blaze. The truck has been declared a total loss. …”

   NHTSA complaint #707651, filed 1999-06
3. 3
   Vehicle speed control

   Accelerator pedal sticking or sudden acceleration

   • 6 complaints (11%)
   • median 135,000 mi at 24.0 yrs old (1 states mileage, few)
   • 1 mention a crash, fire or injury
   • filed 1996–2015

   Owners describe an accelerator pedal or cable that sticks, so engine speed does not drop when the pedal is released, and in some reports the vehicle failed to move when the pedal was pressed. Some describe a rubber cable guard melting into the cable at moderate speed, and others describe sudden acceleration when shifting from a lower to a higher gear. Some owners pulled over and adjusted the pedal, but the sticking returned intermittently, and a report says the vehicle was not included in a campaign for vehicle speed control. Mileage is listed only for the stuck-cable report, at about 135,000 miles, and the others list none; the sticking and sudden acceleration are described at moderate to highway speeds.

   What to check: Ask whether the accelerator cable and pedal have been inspected for sticking, and whether the cable guard or linkage has been replaced. On a test drive, press and release the pedal repeatedly and confirm that the engine speed drops immediately.

   2 excerpts from owner complaints in NHTSA records

   “While applying the brake pedal consumer heard a loud squeaking noise and vehicle vibrated uncontrollably. Vehicle was taken to the dealer for inspection, and mechanic determined that the brake pads needed to be replaced. Also, consumer noticed that while applying the accelerator pedal vehicle failed to move and the accelerator pedal stuck.”

   NHTSA complaint #10101401, filed 2004-11

   “The contact owns a 1991 Isuzu Trooper. The contact stated that the accelerator cable was stuck which caused the accelerator pedal not to release. The failure was progressing more frequently. The contact stated that the engine speed would not immediately decrease upon the release of the accelerator pedal and the vehicle was pulled over to adjust the pedal; however, the failure recurred intermittently. The vehicle was not included in NHTSA campaign number: 04v199000 (vehicle speed control). The vehicle was not repaired. …”

   NHTSA complaint #10683039, filed 2015-02, 135,000 miles
4. 4
   Tires

   Tire tread separation at highway speed

   Mentioned in 4 of 25 sampled complaints

   Owners describe tread separating from the tire, often after noise or vibration, and some lost control while driving. Some describe the failure as sudden, and a report describes a rollover with fatal injuries after the rear tread separated on a highway. Some reports name the same tire model, and a report describes an earlier separation of the same tire type on the same vehicle. None of these reports list mileage, and they were filed between 2000 and 2001; some describe the failure at highway speeds.

   What to check: Check the tire age from the DOT code and inspect each tire's sidewalls and tread for bulges, splits, or uneven wear. Ask a tire shop to check all tires and confirm whether any tire recall applies to this vehicle.

   2 excerpts from owner complaints in NHTSA records

   “Pe00 020; consumer was traveling 75mph on highway and lost control of vehicle because rear tire tread separated from tire, and flipped multiple times. Driver died from head injuries, I person was injured, tires were bridgestone desert dueller, size p235/75r15, DOT wk13356.”

   NHTSA complaint #882658, filed 2001-03

   “Original equipment on 1991, Trooper, p235/75r15 size. Tread on left rear tire separated at highway speeds. Consumer states vibration started at 40 MPH and the failure was sudden, bridgestone desert dueler tire.”

   NHTSA complaint #893441, filed 2001-08

Buying note. Ask for records of transmission, fluid, and engine-cooling repairs, and confirm whether the listed recalls have been completed. Because accelerator sticking and tire tread separation are also reported, check the pedal return and the age and condition of the tires during a pre-purchase inspection.

Summary written with AI from a sample of 25 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.