Nissan hardbody cuts out at 2200 rpms!

[john1]

90 Nissan hardbody 4x4 V6 runs great until the tach reaches 2200 rpms then cuts out like the key was turned off. When the tach drops back to 1500 rpms it continues to run fine. It will repeat this under any conditions. I've replaced the airflow meter and the ECU. I've also checked the fuel pressure and ran some new ground wires to the motor and cab. At one point it started running fine for about 250 miles and then right back to its old tricks. HELP! Does anybody have any ideas or similar experiences?

[Big-Bird]

The manual for the D21 points to a few items you need to check:

Timing system: Damaged cap +/or rotor, loose distributor lock nut, damaged wires etc.

EGR system.

PCV system, check the valve and see if it functions properly.

Vacuum leak(s)

Clogged fuel filter(s). Check for metal and rubber fuel line damage.

I can't seem to find any info on whether or not your D21 has a Throttle Position Sensor. If it does, this can also prevent RPM's from going over 2500.

I wish I could offer more insight here.

[YEPEE]

sounds like its in "failsafe" did you pull any codes??