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edcmat-l1
September 23rd, 2008, 05:32 AM
Having trouble getting an 02 Vette to pass it's monitors. I've tried several combinations of emissions/non emissions/not reported, but they just don't wanna cooperate.
It's a H/C/I car, has cats (hi flow) downstream 02s are in.
It won't pass the 02 monitor, EVAP, AIR.
I have the criteria (ALLDATA) I understand the system very well. Driveability tech for the last 15 years.
I've had several that were difficult, but this one just doesn't wanna pass em.
I've logged the upstream and downstream 02s, and of course they don't work the way the factory wants them to, but like I say, I've had em pass before.
How are you guys setting them up to pass these?

joecar
September 23rd, 2008, 05:50 AM
Edcmat,

Which DTC's did you change the reporting of...?

I know you should be able to get the tests to trigger (i.e. successful drive cycle) in your work bay.

Does it run the catalyst monitor...?

On my 01 F-bird, LT's and hiflow cats, rear O2S present, stock settings on all DTC's, all the monitors trigger after several drive cycles.

I have found that setting the cat DTC's to non-emissions or to not-reported doesn't seem to allow the catalyst monitor to come ready each time I do this (it worked maybe twice that I remember, but not since); (from observing many logs, I see the test is never triggered)...

so, I really don't know, but I might try a full flash.

Cheers
Joe

edcmat-l1
September 23rd, 2008, 07:34 AM
Have tried everything from all DTC settings stock, to trying some of them non emissions, then some no error reporting.
Yes it passes the catalyst.

joecar
September 23rd, 2008, 09:00 AM
You have observed all the individual tests' requirements to run...?

Also, are these the DTC's whose settings you looked at (see attached)...?

edcmat-l1
September 24th, 2008, 04:18 AM
You have observed all the individual tests' requirements to run...?

Also, are these the DTC's whose settings you looked at (see attached)...?

When you say individual test requirements, if you mean enable criteria, then yes. I have all the factory test procedures, enable criteria, etc.
All the DTCs are set as they were from the factory. All the ones you've listed were set to either 1 or 2 trip failure reporting.
Does EFIlive log pending codes? If so it doesn't have any. Next step for me is to scan with my GM scanner to see if there's any pending. Funny thing is, after literally hundreds of miles on it, it hasn't set a single code. Even the 420/430s that usually set with the high flow cats, isn't setting.
Thanks for the suggestions Joe. I'll keep ya posted.

edcmat-l1
September 25th, 2008, 12:05 PM
Went through the Evap system, checked the purge solenoid, vent solenoid using bi di controls (mastertech scanner) tested for a vacuum leak (smoke machine)
Tested the AIR system and found the vacuum line to the valve at the air pump had no vacuum to it when commanding the solenoid on.
Turns out the shop that did the H/C/I swap left the small vacuum hose off the back. I verified this was the problem, at least with the AIR by trying the AC controls. Of course they didn't switch. We connected the vacuum line, had strong output of air to the exhaust check valves.
I haven't driven it enough to see if it will pass any more of them, but I would think that it would at least pass that one.
I'll post again tomorrow after some more driving time.