okidoc

I did a searcj for this and the only post I found dealt w/ this code w/ headers. I don't have headers. So I thought I would ask again.

Here is the story:

I bought the 4runner w/ a cracked intake tube, replaced it that day. No problems. About four weeks later I did an error code check(no dash light but curious to see what was there). i got two codes that I thought dealt w/ the intake tube, temp and flow. Cleared the memory, no problems. Then about ten miles later check engine comes on run the code and I receive a 71 EGR temp.

http://www.off-road.com/toyota/tech/codes/index.html

Checked all connections and EGR operations w/ hand vac pump (engine stalls w/ vacuum on egr at idle)everything seems kosher. Cleared the code, then about ten miles later it comes back on again. Whats up??

No change in driving or performance.

I was thinking it might be the EGR VSV how do I check that. I have a ported vacuum to the regulator but no vacuum from either terminal regardless of rpm and the filter is clean.

What do I do next.

thanks
Dave

AgRunner06

It could also be the modulator. I just replaced that on my step-mom's '96 LC. Sorry I don't know how to check it. I just took a stab in the dark after replacing the EGR didn't fix the problem.

Good Luck

okidoc

When you talk about the modulator do you mean the round black valve thing on the front of the pass side valve cover area?? I think I called it the regulator? How much was it??

mtnfreak

Modulator is the hocky puck sized, UFO shaped thing at the right (pass.) front of the engine. Pretty much any manual describes the test procedure. I got one for about $35 from Bob Bridge Toyota (Google it). That didn't cue the recurring 71 code, though. It didn't stop coming back until I replaced the O2 sensor.

szf2

Checking the EGR modulator is a POC. On the top, it has two vac lines going in and one going out. Rev up the engine to about 3k RPM via an assistant or by turning the throttle lever by hand. Make sure each of the two vac lines coming in has a vacuum (test by sticking your finger on them or w/ a vacuum gauge). Then make sure the line coming out of the modulator has a vacuum. If all this checks, then the modulator probably isn't your problem.

emr88

I was getting Cel Code 71 on my 90 V6 and even though the EGR valve was working (applied vaccum to test) it was still coming up with the error code. I got a junkyard EGR valve, cleaned up the part of the EGV system that goes into the intake manifold (it's a long pipe) and I believe that resolved my issue.

FWIW, my truck failed smog the first time I took it in becasue of high Noxx as a result of the timing being too advanced. Once I cleaned the EGR piping that goes inside the intake manifold, backed the timing off (set to 8 BTDC) it passed the smog test fine and the Cel Code hasn't returned.

***Also, the smog tech I talked to said that the timing needs to be within +/- 3 degrees of factory specs or they will fail you.

okidoc

Thanks everyone for your help and info. I decided to check the egr temp sensor and make sure it was clean, that was when I noticed that it was loose. So I tightened it up and cleared the ECM. Tomorrow I'll see if the code comes back. If it does I think I'll try to replace the modulator, as the vacuum tests leave me thinking that it could be part of the problem.

Could the loose sensor trigger the code?

The stealership wants $50 for it, where is the best place to pick it up cheaper?