phollero

My check engine lights been going on and off for a couple months. Now it is constantly on. The code is 71. I looked it up on google and it is "EGR System Malfunction".

Has anyone had experience with what I should inspect first? EGR Valve? I hear they're hard to remove and don't want to spend the time unless necessary.

FYI, I tried Seafoam in the brake booster line hoping that it would clean out a dirty EGR valve, but no luck.

MIC123321

sometimes you could tap the egr valve with a hammer to losen the build up inside.

link13

EGR valve being clogged can cause this issue. My brother cleaned mine about 2 years ago and I kept getting the intermittent check engine light with code 71. It turned out to be the vacuum modulator, which was about $60.

95ARISTO

I have that same problem too. Does your car shake at all? Mine does when the tranny is in drive and stopped at a stop light. However, it stops shaking once i pop it into neutral. What the heck is going on?

phollero

Well, I DID have the shaking problem when in drive but fully stopped. I had to have the transmission rebuilt. The shaking did not have anything to do with the CEL code 71. Check your transmission fluid level first and change it if it is dirty before spending the dough to rebuild the transmission.

phollero

Thank you, link13
I initially did check the vacuum modulator filter and cleaned it out but CEL was still on. Since you mentioned it, I decided to check it again and completely pulled out the vacuum modulator. I found that the lower line was dirty with carbon deposits and a little water was dripping out . I blew the water and carbon out of the modulator with compressed air and installed it again. I reset the CEL and so far it has not come back. I'll drive it tomorrow and see if it stays off.

Now I'm wondering why there is water in the vacuum lines! Does anyone know how water could be entering the vacuum system?

20lexgs20

If you can get away with it, I would do an egr block off. The emissions people might not like the sight of no egr, but my brother did it on his gs and had no problems what so ever after he blocked it off.

link13

He's in CA, so the EGR block won't fly when he's due for a smog certificate. If it is the vacuum modulator, replacing it is probably better than cleaning it given the fact these cars are getting up there in the years.

20lexgs20

Ol wonderful CA, yea that won't go over so well then. Luckily now in CO we have done away with our emissions!

phollero

Update: After driving 75 miles, the check engine light turned on again with same code 71.

I'm thinking of replacing the EGR vacuum modulator.

My local Lexus dealer price for the EGR vacuum modulator is $79.

link13

That's exactly what mine used to do before I had the modulator replaced in my car. It would sometimes go off again and then would light up again later.