Ok, so I've searched and searched on this and it seems that all I'm getting are bits and pieces. I have some questions about this code 71 that I'm hoping I can get this under control in one shot. So, rebuilt the top end of my motor aft head gaskets went out. Now ive got a code 71 coming up. Runs ok so no issue there. Here is the question. When idling, I remove any and all of the vacuum lines to the egr and to the regulator valve and the motor never changes. Took the sensor out and it looks like new, no carbon on it. I have not changed anything yet. I'd like to check everything before spending any money.

So, if the motor never changes when I remove vacuum lines, does that indicate one thing over another? Any way to test the sensor itself without replacing it?

Thanks

 

Fortunately the EGR temp sensor (code 71) has the same testing procedure for both engines whether it's federal or California emissions. Test per the FSM procedure...just because it's 'clean' doesn't mean it's good. If you get a good reading, test from the ECU harness to be sure it's not an issue with the wiring.

http://personal.utulsa.edu/~nathan-b...00egrgaste.pdf

 

Perfect! I will test it this weekend. Thanks a lot.

 

On post #43 on my 88 rebuild, I show how I have been able to get rid of the code. Probably have alot of plugged hoses. Make sure you have your hoes hooked up correctly on both pieces.