Having smog issues

[waggy401]

Well, this seems to be the place to be, now. Many of you may have seen this on IFSJA.org, but I'll try here, too.

So, after 5 years of sitting, I finally got my 89 Wag running. Now I'm trying to get it to pass CA smog. The visual passed, but my numbers were high. I was hoping someone here could translate the results into a place to start.

My Jeep - Rebuilt the engine in 2007 (went to Ouray that year ) with Howell TBI and all of the TFI upgrade except the coil. Replaced the EGR. When I got it running again last week, I completed the TFI with an MSD coil. It starts right up, but tends to surge a bit while it's cold. When warm, it takes a while for the idle RPMs to drop. I haven't driven it long enough to pull a good log from the TBI computer. The AIR pump has been removed and Edelbrock headers installed, because Howell said I didn't need them.

Anyway, here are the smog results:

15mph test - CO2:13.8 | O2:0.6 | HC:166 (max allowed 115) | CO:0.49 (max allowed 0.63) | NOx:2577 (max 986)

25mph - CO2:14.2 | O2:0.3 | HC:85 (max 95) | CO:0.27 (max 0.83) | NOx:1703 (max 846)

So, do you know if the high numbers are from running too rich, lean, timing off, or...?

I didn't clean the old fuel out of the tank, as there wasn't much left. I put in some stuff that is supposed to restore old fuel along with 15 gallons of new gas. The injectors are firing with what appears to be full force, so nothing seems to be clogged. I will definitely run a couple tanks full and change the fuel filters before trying to smog it again if I can get DMV to give me temp tags. If I remember right, the surging and idle things were going on before I parked it.

[AwesomeJ10]

Is the EGR connected correctly to the TBI? EGR directly affect the NOX.

[waggy401]

Well, I think so. I'll double check.

[FSJ Guy]

You also have high HC (Hydrocarbons). That is unburned fuel. That tells me you're getting TOO much fuel. Even your 25 mph readings are high. With fuel injection, your mixture shouldn't be that rich. Perhaps a misfire or a bad plug? (Or one condition causing the other?)

Did you install a good 3 way cat instead? If you have the OE cat, that may be part of the problem. They were designed to have air injected into them at certain times. I got a TBI'd truck to pass Colorado emissions (roller dyno) with a newer 3 way cat despite having a 401 without EGR instead of the original 360. Talk to the smog referee and see if you can install a newer 3 way cat instead. Yes, it will have to be CARB certified.

[Stuka]

Looks like you are running pretty rich according to your HC numbers. Although there are other things that can cause you to get an incomplete burn. The EGR not working right will also cause issues as mentioned above.

The surging you describe really makes me think not everything is setup the way it should be. I am not familiar with the Howell setup (Pretty sure its based on GM TBI though), but I know with other EFI setups, a floating idle like that can be the TPS, AIC, EGR opening when it should not supposed to.

[FSJunkie]

It would be interesting to see how the TBI talks with the rest of the emission control systems. Most of them are ported vacuum controled. Not all ported vacuum is created equal: the port can be located in different places. Plus, many of the emission controls are designed to work with a specific fuel delivery curve to the engine...and the TBi is probably designed to run without any emission controls.