1995 Blazer 4.3l with 110k (rolled over to 110k this weekend)


Over the weekend, we did a two day 1,000+ mile round trip to St Louis and back home. Near the end of the trip, the engine started idling noticeable strange (up and down). Finally, the CEL come on. Scan Gauge showed DTC P1406 which relates to the EGR.


So, from what I've read in the Haynes (I have nothing better), it appears just a simple cleaning should solve the issue.


Or, is this something far more complex?

 

Sounds about right, Brakleen and a brush should do it.

 

Agreed. Here is some additional info about the P1406 code

P1406 Chevrolet - EGR Valve Pintle Position Circuit

Possible causes
- Faulty Exhaust Gas Recirculation (EGR) valve
- Carbon blockage of the pintle

Tech notes
The P1406 code means that the EGR valve is 10% of the expected position by the Powertrain Control Module (PCM), usually caused by carbon built up in the EGR valve. Start by cleaning the EGR valve.

When is the code detected?
The EGR pintle position was ±10% of the expected position.
Possible symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
P1406 Chevrolet Description
The Powertrain Control Module (PCM) determines that the EGR valve is stuck open if the actual Exhaust Gas Recirculation (EGR) position and the learned closed EGR position vary by more than a predetermined value. The PCM tests for a stuck valve when the desired EGR position is at 0%. The PCM commands the EGR valve to 100% during certain driving conditions in order to clear a possible restriction from the EGR valve if the PCM determines that the valve is stuck open.

 

Thanks for the replies. Hopefully, I can find time to get to it this week.