84 ttype failed smog

[luisturbog]

I have a tt smog chip & failed due to high nox. already installed original air filter hoping that helps & installed new o2 sensor. Could o2 sensor make it fail? mine was lazy. Any help greatly appreciated!

 

[turbojd]

Do you have a cat converter on the car? If so, what shape is it in. Have you checked to see if your egr valve is working properly?

 

[luisturbog]

Do you have a cat converter on the car? If so, what shape is it in. Have you checked to see if your egr valve is working properly?

I have a cat with low mileage on it. I hardly drive the car, well that was because the transmission was bad for 2 years. & the egr valve is good as far as i know. Could egr valve be the culprit causing high nox?

 

[turbojd]

High nox is usually related to the catalytic converter and egr valve. Check the egr diaphram, then start the car and push on the diaphram and see if the car stumbles a little when you do this.

 

[luisturbog]

High nox is usually related to the catalytic converter and egr valve. Check the egr diaphram, then start the car and push on the diaphram and see if the car stumbles a little when you do this.

What should my fuel pressure be set at? & would that affect it? I'm assuming yes.

 

[luisturbog]

High nox is usually related to the catalytic converter and egr valve. Check the egr diaphram, then start the car and push on the diaphram and see if the car stumbles a little when you do this.

Just checked egr & yeah it stumbles

 

[turbojd]

I think with the TT emissions chip Eric says to lower it to around 38lbs. with the line of the fuel regulator.
I have left my fuel pressure at 43lbs. and passed emissions with the TT chip.

 

[luisturbog]

i'm gonna take it to get the smog done today, wish me luck!

 

[luisturbog]

Just an update for all who see this thread. The smog tech told me that my problem may lie with my catalytic converter, apparently it's not heating up enough to burn up excess gasses.

 

[turbolou]

Simply raising the EGR valve with your finger isn't enough to verify proper operation of the system. Jack the car up so the rear wheels are off the ground using a lift or jack stands. put the car in gear while working the throttle gently accelerating & check to see if the EGR valve responds. If so then the system is working if not as I suspect it isn't figuring out why can be tricky as there is a vacuum transducer, switches & vacuum lines that could be at fault. The hot air cars are really bad for this good luck trying to find parts. The other problem lies with the park/neutral feature that has to work correctly to tell the computer that the car is in gear to enable the system to work. Using a scan tool to verify that.Incidentally the speed sensor also has to detect that the car is in motion assuming the the speedo itself works. If that all checks out then the cat convertor is the next place to look.

 

[luisturbog]

Simply raising the EGR valve with your finger isn't enough to verify proper operation of the system. Jack the car up so the rear wheels are off the ground using a lift or jack stands. put the car in gear while working the throttle gently accelerating & check to see if the EGR valve responds. If so then the system is working if not as I suspect it isn't figuring out why can be tricky as there is a vacuum transducer, switches & vacuum lines that could be at fault. The hot air cars are really bad for this good luck trying to find parts. The other problem lies with the park/neutral feature that has to work correctly to tell the computer that the car is in gear to enable the system to work. Using a scan tool to verify that.Incidentally the speed sensor also has to detect that the car is in motion assuming the the speedo itself works. If that all checks out then the cat convertor is the next place to look.

Would putting a vacuum tester right before the egr to see if the vacuum changes work? just to make sure the system is pulling vacuum correctly

 

[turbolou]

You can vacuum test the valve independently but also check to see if vacuum is present at the hose that plugs into the valve when testing the car like I described.

 

[luisturbog]

You can vacuum test the valve independently but also check to see if vacuum is present at the hose that plugs into the valve when testing the car like I described.

Would u know how many inches of vacuum I should see there?

 

[Squid4life]

I still have some spare HA EGR stuff in my garage. I think I have 3 EGR valve, one with a tube, the solenoids, etc. Let me know if you need any of it, or all of it for that matter!

Good luck brother, keep us posted.

 

[turbolou]

Won't take much vacuum to make it work. I guess the new challenge is for owners to play it smart & not modify tier cars to the point of no return with the smog issues that now face the hobby. I'm certain a TR can be built to haul ass & still pass smog. Cam, Heads, turbo injectors, larger stock location intercooler etc. all this is doable but keep it stock looking under the hood & smog equipment intact.