I have a rebuilt '90 7M. It failed aircare with very high NOx readings. It currently has a Lexus Afm, RC 550's, Denso MK IV fp, AFPR, and 3" exhaust. My wideband reads fairly lean at cruise and idle (high 17's) it drops into the high 11's under boost. My fuel press. is set at 30 with vacuum. The max allowable reading here for NOx is 878, and my vehicle reading was 3048. The other readings were ok. I was thinking an SAFC should be my next purchase and go from there? Is there a test to check the EGR system? I'll keep searching, but I'd appreciate suggestions from any members who've been through this type of deal. Thanks. Gawdamm aircare.
Failed Aircare, need some suggestions to troubleshoot
- Thread starter NewWestSupras
- Start date
What is the condition of your catalytic converter, and is it a 2-way or 3-way? It almost sounds like you have a 2-way, as these are only meant to reduce unburned hydrocarbons and CO.
High NOx but what were you other numbers?
We need a complete listing of numbers to guide you in the right direction.
as for testing the EGR....
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=EC&P=17
adam
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=EC&P=20
Cats are three way when stock.
We need a complete listing of numbers to guide you in the right direction.
as for testing the EGR....
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=EC&P=17
adam
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=EC&P=20
Cats are three way when stock.
The HC ppm: 66.00, max allowable is: 87.00
The CO% is: 0.10, max allowable is: 0.59
this is for the driving segment.
The idle test is:
HC: 67, max allowable is: 102,
CO is: 0.00, max allowable is: 0.75.
The cat is aftermarket, so I'd assume its not comparable to stock.
I'll read up on the EGR test, thanks.
The CO% is: 0.10, max allowable is: 0.59
this is for the driving segment.
The idle test is:
HC: 67, max allowable is: 102,
CO is: 0.00, max allowable is: 0.75.
The cat is aftermarket, so I'd assume its not comparable to stock.
I'll read up on the EGR test, thanks.
What RPM or speed (15mph and 25mph?)
hmm
HC are teetering on the edge of failure.
Where do the NOx fall under those numbers?
How hot was the system before you tested? It seems like it might have been cold?
hmm
HC are teetering on the edge of failure.
Where do the NOx fall under those numbers?
How hot was the system before you tested? It seems like it might have been cold?
Here they put you in a booth, and "buddy" does the test. The car was thoroughly warm for this. I only use hi-test gas. I believe the driving segment is 45 kmph. held for 2 mins.
make sure your vacuum lines are ran correctly, your EGR is messsed up. did you clean it out when you rebuilt the engine? and did you clean the passages in the intake manifold??
the lex afm and 550's will give you high HC... but it shouldnt give you high NOx... either EGR or your cat is toasted...
and double check your timing! that has a huge effect on the car during smog!
the lex afm and 550's will give you high HC... but it shouldnt give you high NOx... either EGR or your cat is toasted...
and double check your timing! that has a huge effect on the car during smog!
When was the last time you changed the plugs? And by hot, what exactly do you mean? Drive it like a bat out of hell on the way to the station and no lineup?
Timing is 12 deg. btdc, plugs are NGK iridiums, 3 mos. old. I never cleaned the EGR passages out, I'll get right on that. Thanks.
Post 5 has those numbers...I bought an Safc to better set a/f's. I'm also going to clean out the EGR system. Thats the plan so far.
EGR man.
pull the valve and make sure its not all crudded up. they almost always are.
the head can get jammed up with crap also. thats a bitch, almost have to cook it at the machine shop. (or boil it in tide at home, if you've got a cauldron big enough!)
you can check open / close with just a vac pump on the valve itself.
as for diag on the rest of the system (the stupra's is way complicated for a stupid egr) the manual's got a trouble tree for it.
There are some additives that can cause crazy readings.
Not sure what the stupid corn alcohol does to our cars either.
I know it wiped out the injectors in my Triumph.
pull the valve and make sure its not all crudded up. they almost always are.
the head can get jammed up with crap also. thats a bitch, almost have to cook it at the machine shop. (or boil it in tide at home, if you've got a cauldron big enough!)
you can check open / close with just a vac pump on the valve itself.
as for diag on the rest of the system (the stupra's is way complicated for a stupid egr) the manual's got a trouble tree for it.
There are some additives that can cause crazy readings.
Not sure what the stupid corn alcohol does to our cars either.
I know it wiped out the injectors in my Triumph.