2002 opti Idle goes up on its own

[Malray2520]

2002 200 opti while running on water hose after about 3 min. idle goes up on its own to about 1200 rpms shut motor off restart and idles fine then after 3min or so it does it again whats up?

[EuropeanAM]

Get engine on Computer Diagnostic System for PRINTOUTS of the:

-Run History
-Freeze Frame (Fault) History.

SPECIFICALLY looking for any TPS faults.

Would also recommend that a VOLTAGE SWEEP TEST of the TPS be done. This would include monitoring TPS voltage during the occurance you described above (and if TPS voltage is raising at the point the engine revs up to 1200 RPM's.... it's in the sensor, or it's related linkages).

If no problem is found in the above, test AIR/FUEL pressures. Also, check pressures at 10 seconds after keydown, 20 seconds, and 30 seconds after keydown. Watch for fuel pressure that drops to "match" air pressure (should always maintain it's differential pressure).

[Malray2520]

no tps fault only Pitotckt lo oillvl ckt hi sea tmp ckt Hi trim ckt lo

[EuropeanAM]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by EuropeanAM &raquo;</td></tr><tr><td class="quote">
Would also recommend that a VOLTAGE SWEEP TEST of the TPS be done. This would include monitoring TPS voltage during the occurance you described above (and if TPS voltage is raising at the point the engine revs up to 1200 RPM's.... it's in the sensor, or it's related linkages).

If no problem is found in the above, test AIR/FUEL pressures. Also, check pressures at 10 seconds after keydown, 20 seconds, and 30 seconds after keydown. Watch for fuel pressure that drops to "match" air pressure (should always maintain it's differential pressure).

Were the above also completed? Results?

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[Malray2520]

runing air @85 psi fuel @95 psi at key off air drops to 0 after 5 sec and fuel drops to 40 psi and holds the seam to drop at the same speed fuel just stays @ 40 psi no change on tpi voltage last time I ran it for 10 min and it did not do it?

[EuropeanAM]

You have an air leak, which is resulting in FUEL in the air side of the rails.

ANY air leak will cause this.

Possibilities include (but are not necessairly limited to):

-Air Pressure Regulator
-Direct Injectors
-Direct Injector O-rings
-Air lines
-Air Compressor or Components

You can use a regulated "external air supply" to help determine where the leak is... connected to the port side rail schrader valve. Set regulated pressure to 80 psi.