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CA Smog: Failed This Time. Need Help with Action Plan.

Big T

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Fullerton, CA
Due to our ongoing remodel project on second home up at Big Bear Lake, I've been short of time to focus on the Suburban and it was due for its biannual CA Smog Check. It's passed 3x before with the ATT on, but not this time. Really my mistake for sending the wife to get it smogged AND doing so without the soot trap installed (soot trap is gutted with a straight pipe welded through it). That tipped the guy off and he noted the extra smoke from the Heath tune and then found the orange tube for the vac pump disconnected because I had it laying out in the open from prior work, instead of hidden away. The testing guy is not smart enough to realize that I no longer have a vac pump and the turbo is completely different.

So I'm working on an action plan to get it passed. Fortunately, I have the turbo, upper intake, vac pump and lines from the '95 to work with. I also have the (gutted) soot trap that installs in place of the muffler. '

So my questions are:

1) The '99 has the alternator over on the side where the vac pump mounts, whereas the '95 has the AC compressor. The vac pump bracket has 2 bolts that mount into the AC compressor, a third that mounts through a pivot tube off to the passenger side, and the two nuts that go onto the water pump bolts. I have not torn into the '99 yet as I wanted to ask this inquiry here. Will this '95 vac pump bracket work on the '99? Will I have to modify it (ie. cut it) to obtain a temporary installation? The serp belt routing diagram does show the vac pump in the same position as the '95. It looks awfully tight in there on the '99, whereas we were pulling it from the '95 wreck that no longer has the radiator or fan installed as they've been harvested and installed on the '94.

2) Will the smoke on the snap test lighten up with the GM 5 turbo installed with the Heath Tune? My hope is that a quicker spooling turbo would offset the added fuel from the Heath Tune.

We did a side-by-side snap test using my son's '94 with ATT and adjustable Buddy Tune and my '99 with the ATT and Heath Tune. On the economy setting, the '94 has a slight puff of black smoke. On the Race setting No. 4, it smokes on the level of my '99 with the Heath Tune.

Initially, I thought I would just tear into the '99 today to put the GM 5 turbo, vac pump and soot trap on and get it tested, but don't want to do so until I get more definitive answers on the vac pump bracket. Just don't want to have the truck down while waiting for answers. I'm going to go pull the rotors on my Honda to have them turned and I'll be contemplating my fate on the '99 Suburban.
 
vac pump is the same no matter what year. Probably would smoke less with a gmx turbo for the snap test

Thanks. With more daylight (no jab intended) I can see that there's a bracket on the alternator that will take the vac pump and the rest looks the same. I'm going to take this job on the following weekend.
 
Why not put the kitty back in(even though it is gutted), tidy things up, and take it somewhere else for smog. Since you said it has passed before, why shouldn't it now.
 
Why not put the kitty back in(even though it is gutted), tidy things up, and take it somewhere else for smog. Since you said it has passed before, why shouldn't it now.

That was my son's recommendation and I will make an attempt at this. Just checking into whether they log attempts and how many you get.

Next level would be to install the old stock stuff and try.

Final level would be stock stuff plus stock ECM.
 
You failed the smoke test? What did it measure or was it plugging the sensor up?
Does it hold a steady redline without jumping or missing?
You can find a tank of B99, biodiesel, it will drop the smoke numbers. Low as you dare on fuel and fill it on B99. If it is reading a smoke number at all B99 will get it to pass. Otherwise it is smoking so bad the sensor is fouling out and B99 won't help enough.

And kitty, empty or not, wasn't present? :nonod: That will fail you... IMO the kitty doesn't help with smoke. A plugged kitty hurts you.

Vac lines on the emissions label need to go somewhere. No vac lines on emissions label - no problem. Your CA label may differ from the FED label. The lines need to disappear if they are not on the label. Loop the vac solenoid to itself as they don't know what it is. Neither do you if they ask.

I would swap the stock ECM in the 1999 as it would have the least smoke vs. a Heath tune. You know how to clear codes and be easy on it so you don't set a code with the ATT on the way there with a stock tune. If the '99 has a MAF it may be difficult or impossible...
 
Joshua, the smoke test is a visual. No equipment or sensor is used.

As noted, due to time constraints, I did not install the kitty and sent my wife in for the test. It was a progression: no kitty had him looking > found disconnected orange vac line > claimed he observed 2 to 3 seconds of smoke on the accelerator snap test.

So I will install the kitty and get rid of the vac lines. I'll also cut the sticker on the K47 box showing the vac line routing. I'll take your advice and drain the tank and put in 5 gallons of biodiesel and take it another testing station. If that does not pass, the. I have to resort to installing the GM 5 turbo and vac pump. I do not have a spare stock tune ECM laying around. All the programmers typically have a core charge for those, so you're trading stock ECM for the tuned ECM. Worst case, I have to buy an ECM with a stock tune.
 
Kitty is not going to reduce the smoke.

You just have to make sure that they do not stomp hard on the gas pedal.
 
Kitty is not going to reduce the smoke.

You just have to make sure that they do not stomp hard on the gas pedal.

The kitty that I will install has had it's core removed and a straight through pipe welded in place. It's a faux kitty that's nothing more than a section of 4" pipe with a kitty shell around it.
 
Do not cut or modify the emissions label!!! They will look it up in the book after going "Hmmmmm...." If they complain about the vac lines again then they need to go to 'things'. If the 'things' are decoration or functional is another matter.

The smoke test as I know it is invalid from a visual - all old diesels can smoke some when snapped and still pass - it is the steady state smoke they measure. Last I knew they were supposed to use a smoke sensor for the snap test.
 
Do not cut or modify the emissions label!!! They will look it up in the book after going "Hmmmmm...." If they complain about the vac lines again then they need to go to 'things'. If the 'things' are decoration or functional is another matter.

The smoke test as I know it is invalid from a visual - all old diesels can smoke some when snapped and still pass - it is the steady state smoke they measure. Last I knew they were supposed to use a smoke sensor for the snap test.
California uses a visual snap test as this had quite a bit of debate when it came out.
 
California uses a visual snap test as this had quite a bit of debate when it came out.

Yep, and every time before this station was satisfied with the visual. This time I tried to get away without the kitty because they never checked for it before. Bad idea and one thing lead to next and it affected his opinion on the snap test.
 
My 97 has not failed yet. It came close in 2008 when my center mount turbo had leaking tubes. Still barely passed. My last test was 0,0,0. Then again i took it on a nice highway run up to 90 mph a couple times and then let it fast idle for another 20 minutes then i drove to the test place and went in right away. Once these are hot they run pretty clean!!
 
Go to another station!

Unless CA regs specifically called for them, IIRC cat's were OE only in 97 & 98's which is why I narrowed my search to just 99's.

If cleaning up the vacuum lines, getting the engine warm prior to the test, and / or going to another station does not 'fix' it, think about another tune or a GM8 as my Heath tune still smoked a bit when I got over 2K RPM's.
 
Go to another station!

Unless CA regs specifically called for them, IIRC cat's were OE only in 97 & 98's which is why I narrowed my search to just 99's.

If cleaning up the vacuum lines, getting the engine warm prior to the test, and / or going to another station does not 'fix' it, think about another tune or a GM8 as my Heath tune still smoked a bit when I got over 2K RPM's.

CAT CONVERTERS started on the 6.5 in 94 when the DS4 injection pump came out, and to my knowledge ALL 6.5's with DS4 pumps had a cat converter on them. The federal emission LB7 DURAMAX is the only DURAMAX that didn't have a cat converter on it either, so for the most part GM diesels from 94+ had them except for federal trucks from 01-early 04.
 
Propane inj?

I've had some very good input, much of which will be put into play. Just like troubleshooting, start with the cheapest solutions and work up from there. I'm putting the (gutted) kitty on, stuffing the vac lines out of the way, emptying the tank and putting biodiesel in, warming it up and going to a different smog check station. Hopefully, that will be enough to get it done. If not, I'll put the GM 5 and vac pump on and try that with biodiesel. I don't think propane is in the equation.

Have they come up with an adjustable tune for the OBD II trucks? An adjustable tuner with a stock or economy setting would solve my snap test problem.

BTW Colby's Burb is humming along and performing nicely.
 
the vac pumps look identical, but IIRC the 94 and 95 are threaded, and the 96+ are drilled out for straight through bolts. something like that, as I couldn't use my 1997-early 99 engine's vac pump in my 95. IDK, but am pretty certain that the 95 and older bracket wont work.

any junkyards around to get stuff? If you are short, I may be able to come up with a pump and bracket from a 96+ I'd let you borrow. we could insure the shit out of it and hope USPS looses it on the way back to me, and then we could split the proceeds and blow it at Leroydiesel.com. :)

I would do a little more research and see if it negatively impacts you if you test at a different location? have you been using the same spot for years, or just whoever offers smog check services? I would say a fresh air filter and fuel filter, some power service silver bottle, and a quick trip around town to warm it up fully would go a long ways to get it to pass.

good luck!
 
It is very subjective (visual) so if you can find a station with people who does not know nothing, it will passed.

Putting a fake kitty should pass visual inspection.

Make sure there is no left over vacuum lines.
 
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