FAIL: LT1 Swap Can't Pass Emissions
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Staging Lane
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I have a Volvo 740 wagon with an LT1/T56. Fun daily driver / sleeper / family truckster. More photos here. The wagon does not have catalytic converters.
It failed its annual emissions test Wednesday, then again today. I didn't do anything to the car in preparation for Wednesday's test because it passed last time (11/06). The only difference in the testing vs. 11/06 is the engine listed on the emissions documentation was the 2.8L V6 (Wednesday's test was 2.3L). Unfortunately I don't have the results from the 11/06 test.
03/05/08:
25/25 Test
HC ppm: 107 / 162 Allowed: Pass
CO%: 2.41 / 1.04 Allowed: Fail
NOx ppm: 835 / 1163 Allowed: Pass
RPM: 2323 / 3000 maximum
CO+CO2: 15.3 / 6.0 minimum
50/15 Test
HC ppm: 111 / 167 Allowed: Pass
CO%: 1.73 / 0.94 Allowed: Fail
NOx ppm: 1279 / 1273 Allowed: Fail
RPM: 2134 / 3000 maximum
CO+CO2: 14.8 / 6.0 minimum
03/07/08
The changes:
HC ppm: 57 / 157 Allowed: Pass
CO%: .84 / 1.00 Allowed: Pass
NOx ppm: 1056 / 1121 Allowed: Pass
RPM: 2402 / 3000 maximum
CO+CO2: 14.3 / 6.0 minimum
50/15 Test
HC ppm: 201 / 162 Allowed: Fail
CO%: 0.81 / 0.91 Allowed: Pass
NOx ppm: 2516 / 1277 Allowed: Fail
RPM: 1046 / 3000 maximum
CO+CO2: 14.1 / 6.0 minimum
You can tell a car passes if the test ends before all the time runs out, so we knew it passed the first test. He tried the 2nd test three times (the limit) in 1st, 2nd and 3rd gear (the results are from the 3rd gear attempt, note the low RPM).
From research: ASM2 or Accelerated Simulation Mode Test - A dual-mode test including a 25/25 test = 25 pounds of load at 25 MPH and a 50/15 test = 50 pounds of load at 15 MPH.
The shop owner's son did the test, and he said I could come back later and have them try some things under the hood using the tester in "manual" mode. $50 if they can get it to pass (plus another $25 since I've used my free retest), no charge if they can't.
I'm wondering if I shouldn't just buy a pair of converters... $100 plus my time to install...
Your thoughts? Thanks!
It failed its annual emissions test Wednesday, then again today. I didn't do anything to the car in preparation for Wednesday's test because it passed last time (11/06). The only difference in the testing vs. 11/06 is the engine listed on the emissions documentation was the 2.8L V6 (Wednesday's test was 2.3L). Unfortunately I don't have the results from the 11/06 test.
03/05/08:
25/25 Test
HC ppm: 107 / 162 Allowed: Pass
CO%: 2.41 / 1.04 Allowed: Fail
NOx ppm: 835 / 1163 Allowed: Pass
RPM: 2323 / 3000 maximum
CO+CO2: 15.3 / 6.0 minimum
50/15 Test
HC ppm: 111 / 167 Allowed: Pass
CO%: 1.73 / 0.94 Allowed: Fail
NOx ppm: 1279 / 1273 Allowed: Fail
RPM: 2134 / 3000 maximum
CO+CO2: 14.8 / 6.0 minimum
03/07/08
The changes:
- Clean K&N air filter, not re-oiled
- New NGK V-power plugs, gapped at .050 (I think I didn't check the gap last time, some were as high as .065!)
- 1 gallon denatured alcohol mixed in to ~7 gallons of gas
- Removed the ignition box (the car wouldn't rev over 4500 unless I disconnected it, this was before the new plugs)
- Tested as a 2.8L, note some of the limits are lower
HC ppm: 57 / 157 Allowed: Pass
CO%: .84 / 1.00 Allowed: Pass
NOx ppm: 1056 / 1121 Allowed: Pass
RPM: 2402 / 3000 maximum
CO+CO2: 14.3 / 6.0 minimum
50/15 Test
HC ppm: 201 / 162 Allowed: Fail
CO%: 0.81 / 0.91 Allowed: Pass
NOx ppm: 2516 / 1277 Allowed: Fail
RPM: 1046 / 3000 maximum
CO+CO2: 14.1 / 6.0 minimum
You can tell a car passes if the test ends before all the time runs out, so we knew it passed the first test. He tried the 2nd test three times (the limit) in 1st, 2nd and 3rd gear (the results are from the 3rd gear attempt, note the low RPM).
From research: ASM2 or Accelerated Simulation Mode Test - A dual-mode test including a 25/25 test = 25 pounds of load at 25 MPH and a 50/15 test = 50 pounds of load at 15 MPH.
The shop owner's son did the test, and he said I could come back later and have them try some things under the hood using the tester in "manual" mode. $50 if they can get it to pass (plus another $25 since I've used my free retest), no charge if they can't.
I'm wondering if I shouldn't just buy a pair of converters... $100 plus my time to install...
Your thoughts? Thanks!
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OP, I'd say if you can get a pair of cats on it quickly on/off just throw some on there and go try again. Also if you have tuning capabilities you could maybe lean it out a tad bit and drive it easy the way to the shop. I'm glad Indiana doesn't have these stupid tests.
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Leaning it out will cause the Nox to go higher, especially if he does not have a EGR. I would recommend getting a cat. They will help the car pass the smog test so much easier then all these little tricks to the gas and that sort of thing.
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I have a Volvo 740 wagon with an LT1/T56. Fun daily driver / sleeper / family truckster. More photos here. The wagon does not have catalytic converters. and fails smog test.
Im just going to buy cats for a 100 dollars to fix the problem
Thanks! for reading my thread
Im just going to buy cats for a 100 dollars to fix the problem
Thanks! for reading my thread
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Magnaflow bullet converters installed; result: FAIL.
I was told the cause was high NOx and it was because the engine was running too lean (???). The NGK TR55s were replaced with Delco 41-906 platinums (OE plug) and the wagon passed. As was pointed out on a Volvo forum, the lack of EGR may be one cause of high NOx (shorty headers with no EGR provision).
25/25 Test
HC ppm: 152 / 157 Allowed: Pass
CO%: 0.90 / 1.00 Allowed: Pass
NOx ppm: 157 / 1121 Allowed: Pass
RPM: 2290 / 3000 maximum
CO+CO2: 14.7 / 6.0 minimum
50/15 Test
HC ppm: 149 / 162 Allowed: Pass
CO%: 0.91 / 0.91 Allowed: Pass
NOx ppm: 999 / 1227 Allowed: Pass
RPM: 1989 / 3000 maximum
CO+CO2: 13.0 / 6.0 minimum
Look at the CO% on the 50/15... 0.91 out of 0.91 allowed. Yikes.
I spent a lot more than I wanted, but I just didn't have the time to do the work myself (major house renovations). Also if I had done the work the shop would not have worked as hard trying to get it to pass. The exhaust is a bit more muffled and the drone is gone.
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MSD Opti, shorty headers, K&N canister type filter, No MAF, PCM programming stock except for MAF/ VATS/ CAGS delete and change gearing to 3.73. Maintenance items like O2 sensor, wires, etc are relatively recent.
290 rwhp / 325 rwtq.
290 rwhp / 325 rwtq.
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Glad to hear it finnaly passed , so much for listening to all the "experts" , btw sweet swamp , i havent tryed yet and am riding outlaw style , time for me to bite the bullet and just go
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Bump from the dead. The wagon failed emissions again last year, and I had the shop find the cause. Turns out the air intake sensor was mangled. Sensor replaced: pass.
Last years test results aren't handy, but the wagon took its last test today (no changes from last year, just regular maintenance).
25/25 Test
HC ppm: 90 / 162 Allowed: Pass
CO%: 0.79 / 1.04 Allowed: Pass
NOx ppm: 804 / 1163 Allowed: Pass
RPM: 2373 / 3000 maximum
CO+CO2: 14.0 / 6.0 minimum
50/15 Test
HC ppm: 82 / 167 Allowed: Pass
CO%: 0.65 / 0.94 Allowed: Pass
NOx ppm: 992 / 1227 Allowed: Pass
RPM: 2158 / 3000 maximum
CO+CO2: 14.0 / 6.0 minimum
No more tests after this year, the wagon will be 25. By the way the wagon is for sale. Sad to see it go, but the family has outgrown it.
Last years test results aren't handy, but the wagon took its last test today (no changes from last year, just regular maintenance).
25/25 Test
HC ppm: 90 / 162 Allowed: Pass
CO%: 0.79 / 1.04 Allowed: Pass
NOx ppm: 804 / 1163 Allowed: Pass
RPM: 2373 / 3000 maximum
CO+CO2: 14.0 / 6.0 minimum
50/15 Test
HC ppm: 82 / 167 Allowed: Pass
CO%: 0.65 / 0.94 Allowed: Pass
NOx ppm: 992 / 1227 Allowed: Pass
RPM: 2158 / 3000 maximum
CO+CO2: 14.0 / 6.0 minimum
No more tests after this year, the wagon will be 25. By the way the wagon is for sale. Sad to see it go, but the family has outgrown it.