Engine

2001 JEEP CHEROKEE
4WD • AUTOMATIC
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BEVMATHERLY
  • MEMBER
  • 1 POST
Installed new long block in a 2001 Jeep Cherokee 4.0L. Upon starting for the first time, the engine goes to full throttle (runs away)while the throttle plate remains closed. Some backfiring occurs. We immediately turn engine off when it starts to rev. What could possibly be wrong?
Jul 5, 2011 at 3:31 PM
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RIVERMIKERAT
  • ✓Experienced Mechanic
  • 6,106 POSTS
Backfiring means a timing issue, either crossed plug wires or timing set incorrectly. Make sure the pressure regulator is working properly. If there is too much pressure getting to the injectors, they will spray more fuel than normal and cause the engine to run faster than desired.
Jul 5, 2011 at 4:40 PM
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