mpm86

Hello:

I have a 1994 GS 300 with the dreaded Code 71.

I have seemingly tried everything.

I have replaced with new, the following:

1. VSV for EGR

2. EGR Modulator

3. EGR Valve

4. EGR Temp Sensor

5. All Vacuum Lines in EGR system

I am still getting the code 71 which is preventing me from getting the car smogged.

Does anyone have any idea as to what I should check next? I am stumped.

Thanks in advance.

Titten

Is that the code that comes right after code 70???

Nixspeed

Have you checked the passage way for the egr system? They get clogged with carbon and won't allow anything to pass through. Its on the back of the head if I remember right. Mine is JDM so no egr thank god. I hate that entire setup.

mpm86

When I had the EGR valve out, I sprayed throttle body cleaner into the intake plenum but I have not removed the intake plenum to clean it meticulously yet. There did not seem to be a lot of carbon at the point where the EGR valve connects to the intake plenum, so I was hoping that was not the issue. Seems like a big job and I was hoping to exhaust all other solutions before going that route.

Nixspeed

Yeah it is a pain but most likely your issue. I've fixed every egr problem by just detail cleaning the system. It sux but its almost free.

mpm86

Just a quick update, cleaning the EGR passages did the trick.

It was time consuming getting the intake plenum off.

The passage was completely plugged. I let Seafoam soak, cleaned with pipe cleaners, then blasted the EGR passage with my air compressor.

Thanks for the help.