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Discussion Starter #61
A couple of things:

  • Is the car fully warmed up? Coolant temp of less than 170 seems low… do you have a different thermostat or something? Should be around 190. May not be impacting anything but not sure what the threshold is to go into closed loop.
  • The o2 sensors you have shown are the correct ones… not sure why you aren’t getting data from bank 1 sensor 1. Could be a wiring issue or issue with the O2. Do all your datalogs not have data for that now?
  • In the first log at 3k rpm, the bank 2 sensor shows you are basically fully rich (O2 sensor voltage near 1). This could potentially be because your bank 1 sensor has an issue, so the ECU is not using closed loop at all to cycle around 14.7 AFR. This would definitely result in high hydrocarbon emissions.
  • In the 2nd log at idle, you still don’t have data for O2 in bank 1, but at least bank 2 sensor is doing what it should – when the ECU is in closed loop using the O2 to target 14.7 AFR, you should see the voltages cycling like that (from low to high, trying to get to 0.5). However, I know from when I had an issue with one of my O2s, I would not be anywhere close to 14.7 AFR with only one O2 working. You need both working properly. This is important for emissions. It would not however affect high load/boost driving because you are not using the NBO2s at all (as it is in open loop).
  • You are getting knock readouts… its just zero. This is good. There is no such thing as “good” knock. If you see knock, you have an issue, especially if it occurs under boost.

I don’t have fuel trims on in my logs but I don’t think they should be nearly at -100 all the time like that. It seems like you are over fueled. What are your mods? Stock ECU/tune/fuel system?
 

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My system is completely stock. Why is it running rich?
Those timing numbers of 18 + 19 do I divide number to get the actual timing? what is target range either way?
I just need to pass a stupid Idle test for emissions.
What do I need to do?
 

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Discussion Starter #64
My system is completely stock. Why is it running rich?
Those timing numbers of 18 + 19 do I divide number to get the actual timing? what is target range either way?
I just need to pass a stupid Idle test for emissions.
What do I need to do?
This log does not show it running rich. Looks like both O2s are cycling so your AFR should be ok. The timing numbers are the actual timing advance. I just looked back at one of my logs and yours looks completely normal from what i can see; I had 17-19 degrees of timing at ~900 rpm idle. What did you fail the test for, HC? NOx? CO? Do you have precats in place? Main cat? OEM? Stock EGR and EVAP still in place? Is EVAP OEM and potentially clogged? I would start considering other issues than your actual engine, although the log may not definitely confirm you dont have misfires that could be resulting in high emissions.
 

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I failed for both carbon monoxide and hydrocarbons the stock Cats r in place.
The EGR and all that crap is deleted pursuant to the vacuum hose delete. Is it possible that
The cats are all clogged because of crappy tuning?
I used to get gas and black gunk coming out the tailpipe all over the concrete before I fixed all the problems leading up to today.
 

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Discussion Starter #66
Sure does seem like a cat issue then... I assume there is no visual inspection since you don't have issues with EGR delete. If i recall correctly, EGR does not necessarily operate at idle (light cruise only?) but I am not 100% sure. I think the EVAP being deleted could affect HC emissions, but not sure about from the tailpipe, since its basically just capturing those venting from the gas tank... What else is done to the car besides the vacuum reduction? I only get the "black gunk" coming out of the exhaust after going 100% catless. When i had the main cat in place i never got that at all, even with no precats. It might be worth dropping your main cat to at least take a look at it. I wouldn't say clogged, more like potentially fouled. Did you make sure the car was fully warmed up and ideally drive it really hard before doing the test? You want the cat as hot as possible. If you knew someone else with a main cat to swap in for the test that might be worth a try...
 

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Discussion Starter #67
Also, do you get any smoke on decel or idle? Bad VSS can lead to high hydrocarbons; not sure about CO.
 

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I passed emissions before in Arizona with no smog equipment is it possible it's bad valve stem seals?
No smoke at idle or on deceleration or anything. And yes you are correct there is no visual inspection.
Thank you again for your time I really appreciate it.
 

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Discussion Starter #69
Well yes, it could be VSS. How old are they (miles, years)? Now that i think about it you may not see as much visible smoke from them since you still have your cat in place. I didnt really see the clear indication of smoke from decel until i went completely catless.

I'm not sure what other relevant data you can get from your datalogs or how you can further narrow down the issue. I think the easiest thing to do at this point is drop your main cat, take a look (not going to be super helpful unless there is an obvious issue), and perhaps swap it out for another cat you know is good and retest. And when you retest, make sure the cat is as hot as possible.
 
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