smog gods are against me!

the jeep blew a rear end last year so it sat on nonop for a year got it back togther got a one day per mit to take her down to smog her she failed miserably!

its a 90 xj stroker auto on 33's with 3.55's. all sensors were replaced with the stroker rebuild under 10,000 miles its run only on chevron 91 octane.

heres the results


the following tests have been done:
ran vacuum directly to the EGR went from nice idle to rough running

hooked direct vacuum to transducer blew in bottom (back pressure) vacuum go's through transducer

the solenoid has power when the fuel pump is running no vacume can get through when energized when its not energized vacume go's right through

the trans ducers back pressure line is clear

that leaves me with three ?'s
1. what tells the solenoid to deenergize?
2. is there a way to test that part?
3. is the cat the only other thing it could be going by my current list of things tested?

i need to get this thing to pass before 6/22 (reg is due:hang

all help is greatly appriciated
-Chad

Am I reading wrong--looks to me like the EGR passed, you just need a new gas cap?

Anyway, isn't what failed you the NO readings? That would be too lean I think.

Before you spend money, go to the website and see if you qualify for money towards repairs.

Looks like ya need a new gas cap.....

Nick

joe_peters said:

Am I reading wrong--looks to me like the EGR passed, you just need a new gas cap?

Anyway, isn't what failed you the NO readings? That would be too lean I think.

Click to expand...

from what the smog guy told me the no is controlled by the egr system.

I just got mine smogged after it failed barely.
The state web site is http://DriveHealthy.com
Mine became a "gross polluter" after the first test when I accidentally swapped the two vacuum lines at the back of the air cleaner trying to get it to pass. Once the lines got put back it was slightly better than yours and didn't fully qualify for repair help, but my mechanic convinced the BAR that I wanted the Jeep to be really clean. We got the oxygen sensor replaced and the NOx went from around 3000 with swapped lines to 170 w/new sensor!

Replace your fuel cap - it's obviously toast.

If the EGR causes the engine to stumble at idle, then it's working properly. Check the solenoid by applying +12VDC to the terminals at idle - your engine should stumble again (that means the solenoid is functioning.)

I don't see where you say you've replaced the cat - probably a good next step. Get a BBChevvy catalytic converter, since you don't have OBD to hassle with and you'll get more flow out of it. I know the BBC cat will pass smog on RENIX - I've done it on three different rigs!

The "Thermostatic Air Cleaner" (useless on a FI vehicle...) is the corrugated tube that runs from the sheetmetal shroud on your header to the side of the airbox snorkel. It's a standard part, just go get a replacement and call that good.

A failing HEGO can cause a "lean" condition, which will increase chamber temperatures and cause NOx formation. A failed HEGO causes the ECU to run in Open Loop mode - which is rich, and will decrease NOx.

Recommendations:
- Replace Fuel Cap
- Replace intake preheater hose
- Replace Catalytic Converter (especially if original)
- Replace HEGO sensor (especially if original.)

hego? whats that?

any recomend dations on what year model chevy to order the cat for?

DesertRunner said:

hego? whats that?

any recomend dations on what year model chevy to order the cat for?

Click to expand...

HEGO = Heated Exhaust Gas Oxygen Sensor

DesertRunner said:

hego? whats that?

any recomend dations on what year model chevy to order the cat for?

Click to expand...

Joe got it right - HEGO = Heated Exhaust Gas Oxygen (sensor.)

For the cat, just have the counterman grab his paper catalogue and pick an application that only uses one cat for both sides. I think the 1970's and 1980's Chevvy C/G/K-series are good choices for that sort of thing. I don't recall the apps I use - I always end up looking it up again whenever I have to go in.

Cut the flange off of the OEM cat and save it to weld onto the new one - especially if you have a manual! Being able to easily detach the exhaust setup at that particular point saves you loads of work at times, particularly on clutch jobs...

I just failed with better results (my fails were in the 600-700 range) but still fail. The guy told me the same thing as said above:

A failing HEGO can cause a "lean" condition, which will increase chamber temperatures and cause NOx formation. A failed HEGO causes the ECU to run in Open Loop mode - which is rich, and will decrease NOx.

I'm gonna head to Kragen after work and replace these parts...or should I have a shop do it with a pretest since I only get 1 free re-test...