1990 Testarossa Colorado Emissions PASSED!

Hello All,

I've been a member/reader of FChat for years, and couldn't be more grateful for the shared knowledge I've found here... So, I think this is my first post, and I'd like to share my experience with AirCare Colorado.

My 1990 US TR has always been a frustrating vehicle to get running -properly- with fuel mixtures, etc. I have had much more success recently running it -open loop- (unplugged O2 Sensors) and tuning with my Innovate wideband afr device.

In the past I have dealt with emission test like this:
1st Test -- Fail, get numbers, go to parking lot, turn mixture screws 1/4 CCW, get back in line to retest.
2nd Test -- Fail, get numbers, see what percent my 1st adjustment changed, do math, turn mixture screws appropriate amount, get back in line to retest.
3rd Test -- PASS, go home, retune to run better

Since my last emissions test, I did major engine out, and found the precat ceramic matrices to be shattered in the exhaust elbows from heat, impact, etc. So, of course, I cleared out the broken pieces, and reassembled the car with no thought to the emissions. Oh, I also capped and removed the air pump components, which had already been disabled by PO by cutting the drive belt off. No big deal...Until this last week...I need to pass the test for new reg. Ugh. SO, I tried my technique outlined above, no luck, by the time I got CO down, it was running so poorly that HC spiked from missing, pumping unburned fuel through the exhaust.

SEVEN failed tests. Every employee at the testing station had a chance to not only drive my car, but a selfie picture too, when they thought I wasn't watching from the booth windows. I headed home, cry a little, etc, etc.

SO, this weekend I did some work... Re-poked all the plug wire cap terminals after clipping 1/2' off the ends, shined up the plugs, and washed the catalytic converters. Yes, washed them. With Pine-Sol, and hot water, flushing everything backwards of normal exhaust flow. I then shopvac'd everything I could out the cats, always keeping the flow reversed from normal, so any shattered pieces of precat ceramic would be flushed out instead of being driven in more. There were more than a few small pieces that came out, but not more than 50 or so. I did remove quite a layer of black soot, and the cats looked pretty good before I set them to dry overnight with a fan pulling air through them on a workbench. Next morning, fingers crossed, reassembled, retuned -open loop-, looks good, holds steady. My problem closed loop, I think, one of my O2 sensors is bad, so the mixtures go off...I'll save that for another post...

So finally, retested today and PASSED. Passed VERY WELL as my emissions were 1/2 the allowable limits, WOW! Now, I admittedly tuned very slightly lean, but no more than 14.5 AFR (at the tailpipe, so I didn't burn the motor driving to the test station. I also wrapped the disconnected O2 sensor plugs in wire loom sheath as to not fail the "O2 sensor connected" portion of the test.

So, to summaraize, 1990 Testarossa, no precats, no air pump, no O2 sensor input, with washed out catalytic converters, passes Colorado emissions with flying colors.

HC limit 220, CO limit 1.2. I tested at 87 HC, .6 CO.

I think one of my O2 sensors is bad, and I may just replace both, and see what happens next...
Can anyone tell me the benefits of the O2 sensors? Will the car be faster, more powerful or easier to start? I think I have it tuned almost perfectly since passing emissions, and maybe don't need them??

Thanks to all FChat for so many things -john

 

The Pine-Sol idea came out of desperation and too much googling. I had been running the car very rich in the past, with black soot inside the exhaust pathway, I figured it was coating everything. When I first immersed the cat into a 5 gallon bucket of the h/w and pinesol, I got about 1/8 inch of black soot that came right out the cat matrix, and it stayed right on top of the soapy foam layer. After seeing that effect, I set the cats in a slop sink and poured some full strength pine-sol through the matrix, let it sit for maybe 30 minutes, then agitated it all by dunking repeatedly in the bucket, then began flushing w/ hot water from the faucet. The surfaces of the matrix went from jet black to kind of a gray, and the cat seemed to admit much more light when you look straight through. Also the small pieces of fractured pre-cat came out during this flushing.

Honestly, I expected a little heckling about this hacker fix, but I think it made a difference, as it re-exposed much of the previously soot covered surfaces. And at $0 I had very little to lose. I had seen Youtube videos with solvents, acids and additives, all with questionable results... I figured the pine sol was pretty low risk stuff compared to all that.

 

Oh, Turbo-Joe thanks for confirming the O2 sensors' roles as emissions monitors. I kind of figured this was a compliance item rather than a go-faster item.
I am still going to replace the sensors, as I live in colorado and the I-70 corridor has massive elevation change, and I'd bet the sensors would add some value way up at Vail pass almost 11000 ft to keep spark plugs cleaner in the thin air.

 

I have heard of Dave Helms, I think I have even looked at some of his fixes for common issues. I hear he's a wealth of knowledge.

As for the shady shop, it's not done like that here. AirCare Colorado is a company w/ official test stations and a structured test. The technicians really just guide the car through the bays, they don't see results until customer has paid and results have been submitted to a DMV database...

And as for tuning CIS, indeed it is a dark art. I have experience w/ my old 930 turbo, and got some knowledge about it. BUT...The KE-Jet on the TR has a little more -ghost-in-the-machine- factor, coupled with questionable italian engineering, times two CIS systems!

I have been looking for the perfect tune for years, always foiled by some other item on the long list of potential failure points.
The fuse panel
The coolant Y connector thermistor
The THIRTY-SIX (36!) O-rings surrounding the injectors. THIRTY SIX!
The fuel pumps
The injectors
The stupid, cam driven vacuum pump and it's sheared shaft
The SLOW DOWN light thermocouples
The fractured pre-cats
and now, O2 sensors.

A trip to a ferrari mechanic for even a couple of these items will be a fortune, so I love FerrariChat for those reasons.

Tuning the CIS is not that hard, but the journey to get it tuned correctly seems to have passed through every one of the items I listed above...It has taken me years to learn, and I'm sure I'm not quite there yet.
My tuning kit includes:
AFR Gauge
CIS pressure gauge
Homemade manometer

As for the THIRTY SIX Orings around the injectors?? The injector bore sizes in the testarossa head require adapters to fit CIS injectors. Funny thing though, the 512TR injectors (modern piezo electronic) fit the testarossa bores perfectly, no adapter required... I think they planned EFI in blueprint stage, and had to produce with CIS for some reason.

Anyway, whatever, I still love it. All the work I put into the car makes me drive it more, else I get resentful.
People like to see it as well, almost every outing brings a quick friendly conversation with someone, and maybe the world needs more of that?
Also, my car passes emissions with flying colors now! We're all winners with cleaner air!

 

I mean... 36 O-rings in 3 different sizes AND adapter bushings to put round pegs in round holes. Can you imagine the conversations (in German) between the consulting Bosch engineers when the ferrari guys showed them this? On the porsche 930, CIS injectors thread into the intake with one copper sealing ring, simple, sealed forever.