Forgot to mention, if you got those coffee can mufflers in the back, it's gonna affect the EGR system. If the EGR does not get enough backpressure, it will not work, hence, higher NOX.

@CrazySC300 - what is your ignition timing at? it should say it on your smog paper (VIR).

 

Okay, after a couple days of tinkering with the car, It turns out that that both the EGR valve and EGR modulator are both bad...The EGR wasn't holding any pressure...I'm gonna go do a pre-test inspection, and if it fails again....Then it's for sure that one pipe in the back that has to be cleaned.

 

Oh great! Right after replacing both the EGR valve and EGR Vacuum modulator with new units, I get a code 71,With that code, It means that there's a faulty circuit...How can that be possible with brand new units?

 

Are you sure you reconnected the vacuum lines correctly? When you apply vacuum to EGR does it stumble? I got a feeling your EGR VSV is not working. RE-read my previous post how I explain on the operation of the EGR in the previous post.

 

I found a nearly severed EGR temp sensor wire as I was looking around, It's literally only connected by a couple of threads...Just barely! Being that it's an electronic sensor, I wonder if this was the culprit responsible forvthe code 71?

 

After picking the car up, I drove from L.A to Orange to pick something up,I was even stuck in bumper to bumper traffic on the southbound 5, this was about a 45 minute commute...When I got there, I shut the car off for 20 minutes...when it was time to leave, about 5 minutes after getting on the northbound 5 freeway, That's when the check engine light came on...I believed it happened right when I increased my speed on the freeway.

 

Yes. Get a new egr temp sensor. Its giving false info to the pcm becuz broken wire

 

I just got a replacement temperature sensor for $30 at my local junkyard today, If the broken wire on the temp sensor doesn't turn out to be the culprit for the code 71, Then it's for sure the EGR solenoid, which is the last part that hasn't been replaced with a new unit.

 

The egr temp sensor is for diagnostic purposes it does not affect the egr operation. To test the Egr Vsv, all you need to do is apply ground to it when the engine is on and the engine should stumble.

 

After so much drama and $1,400+ in repairs, My car finally passed smog and I got my tags...The problem on my car was that just about everything in my EGR system was bad (except for the solenoid) and all the EGR ports were clogged like a ****! But the funny thing was, The CEL never came on...I found out why...A vacuum hose underneath the valve was disconnected! It was on purpose too! because that hose is not easy to find nor get access to, That's why the EGR solenoid couidn't tell that the EGR valve was bad.

I looked at my certificate and saw that my car barely passed the HC part...Max allowed was 57, My car measured at 55...But I think it's because I only drove less than 2 miles to the smog station and my cat converter wasn't really hot enough to do it's job that morning...But the important part was, I passed.

CA smog sucks!