Wath P1406 Code means on a GMC jimmy 1996,

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OBD2 Codes 1996 GMC Jimmy B1265

No on has that it is a body code & not generic

Code 172 is for the fuel system being too rich on bank one.
Code 300 is for a random miss, and code 1406 is for a problem with the EGR valve or sensor.
Each component would need to be tested.

P1406 EGR Valve Pintle Position Circuit Fault
This code is usually caused by carbon buildup in the EGR valve. The carbon deposits prevent the valve from closing completely.

After removing the EGR valve, clean the pintle seat area of the valve and the corresponding passageway in the engine.

or simply replace the EGR valve.

Hope this helps!

P0700 means EATX Controller DTC Present. That means that there is an internal fault inside of the transmission control module, so you'll need a new module.

GM Code P1406=EGR pintle position error. the EGR valve pintle may not be able to move properly due to carbon deposits. It should be cleaned if possible and rechecked.

Uts a problem with your egr valve the pentile is eighter stuck or not sealing correctly . Its likely the valve needs to be replaced

P1406 - EGR (Exhaust Gas Recirculation) Valve Pintle Position Circuit

You most likely have either a defective EGR position sensor or a peice of carbon holding the EGR pintle valve off it's seat.

Hi,you can re check timing, run compression test,

1996 GMC Jimmy no brake lite put in 30 amp and it works

P0301 code means that the the car's computer has detected that one of the engine's cylinders is not firing properly. In this case it's cylinder #1

P0171 code basically this means that an oxygen sensor in bank 1 detected a lean condition (too much oxygen in the exhaust). On V6/V8/V10 engines, Bank 1 is the side of the engine that has cylinder #1. - this could be an open vacuum line.

on your P0301 and your P0171, the first thing I would check is your mass airflow sensor, it's probably fouled, also check the air filter, and vacuum lines for cracks.

P1406 code - EGR Valve Pintle Position Circuit - this basically states that the EGR valve is clogged.