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1991 VR4
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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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1991 VR4
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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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Okay, I'll ask. I'm datalogging just fine, getting great scan rates, all is good.
How do I add the knock sensor because it's not showing on available sensors.
 

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See attached screensot of torque log.

Am I correct to assume that engine load read from Torque needs to be doubled to equal true engine load in the VR4?

Also, I don't see how I can be getting 560% injector duty (Calculated based on RPM*Injector Pulse/1200 = Duty) or 182 ms injector pulses. I have attached a pic of the custom PID it is reading from. Should the pulse formula be divided by 10? At idle I am getting +/- 20 ms pulses.

Idle steps seems off as well, it is in the 40s-50s in boost and doesn't go below 13 at idle.

Any help appreciated.



 

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Discussion Starter · #76 ·
Were the injector PIDs from BlackStealth? I recall he added support for injector-related logging sometime in the recent past but i never really looked into it because at that point i already had my car tuned for my E50 mix so i was really only using the monitoring when i drive it and not longer doing extensive datalogging.

What do you need engine load for? I took a quick look at one of my logs and my engine load is capping at 62.35 because my MAF is maxxing out at 1603. I am also running a SAFC so that is intercepting/modifying my signal.
 

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Discussion Starter · #77 ·
Long overdue update to this thread… its been a long time since the initial post and subsequent follow up with more details.

For the full guide, read these two posts first:

Start here: Datalogging using Torque Pro App and BlackStealth’s OBD1...

Then here: Datalogging using Torque Pro App and BlackStealth’s OBD1...

Since installing the converter the main things I have done are flow tested/cleaned my 550cc injectors, new copper plugs with smaller gap, hotwire fuel pump (denso supra pump), vacuum reduction/EGR delete, and most notable running ethanol mix now. I started with about E40, then E50, now im probably around E75 (not exactly sure at this point, I have just been adding more and more ethanol compared to pump gas and adjusting SAFC along the way, and my E85 tests at 85%, pump gas at 9%). The datalogging is essential for this so I can log and tune based on 3rd gear pulls while watching AFRs and knock. Car runs strong with ethanol as expected. The hotwire was essential for this as the non-hotwired pump could not keep up with 15psi after about 4500 rpm on E50. I do have plans to add the flex fuel sensor in the future.

This post will discuss the addition of oil temperature and pressure sensors to be monitored and logged using the CANBUS device, and only the CANBUS device. I opted to buy the sensors ONLY as it is much cheaper than getting actual gauges (although these typically do have an output you can also wire into the CANBUS device), and whenever I am driving the car, I am running torque for all my monitoring of key engine parameters anyways.

Thus, I recently expanded my setup discussed in the previous posts by adding in oil pressure and temperature sensors. I did this via a sandwich plate after much deliberation as to whether or not I should go that route or get an adapter off the stock location(s). There were pros and cons to each, but the sandwich plate seems to be working well. I got the one from 3sx. The main complaint with this kit is that the included NPT plugs did not thread into the holes – WTF? They were literally in the same package (from prosport) as the plate and the threads were different… Tried all of them in all the holes and none threaded in without cross threading. Aside from everything was fine and there were no leaks; used blue Loctite on the mount bolt for the plate to the block and I run a K&N filter. Photos of setup included in album below.

After installing the plate, you need to install the two sensors. For oil I opted for the 0-100 psi for better resolution but 0-150psi is also supported. For the temperature, only 1 sensor is supported, and you need to either make or purchase from BlackStealth an adapter for the harness in order to connect to the CANBUS device. The other annoying part is that the oil pressure sensor does not come with a full length harness, so be prepared to make your own that is 6+ feet long depending on how you run wires. Its pretty self explanatory how to wire into the CANBUS device following the manual and the labels on the unit itself. I ran the wires along the frame then up to the firewall on the driver side (where my wideband goes from my testpipe) then through the firewall with the million other things going through there near brake booster, and over to my CANBUS device that sits in factory amp location behind radio.

In addition to the hardware, I also had to update my CANBUS device since I was running a much older version. That’s pretty easy, there are instructions from BlackStealth and the software needed is in the zip file, you just need a laptop (windows only I think) and the serial cable discussed in one of my other posts. After the update you need to go in and configure the inputs for your sensors to make sure the correct option is selected (also discussed in my earlier posts). Once you have the hardware and software installed you can at this point start the car and make sure everything is working. Note that the temp sensor has a minimum around 140F so you might not see ‘real’ values right away; the car needs to warm up a little. (You will of course need to add these new parameters to your real time display in torque, but assuming you already loaded custom PIDs, they should already be in the list). Oil pressure will of course be high on cold start and decrease as the car warms up. My oil pressure doesn’t seem to change very smoothly… its almost like its 15 psi increments. It was about 90psi on a cold start, 15 at hot idle, and 45-60 as rpm increases. This is a 100k mile rebuilt engine with 20W50 oil and ½ bottle of lucas oil stabilizer. I changed the oil at the same time and I actually have an oil analysis sent out right now.

Once you verify everything works you can secure all wires and put the device back in place and button up anything you need to. My oil temp warmed up faster than I expected (but still slower than coolant of course) and seemed to stabilize around 210F, which is right around where it should be. This was with coolant around 195F and an 85F day.

Here’s the link two the two specific sensors I ordered. If you are considering ordering others, I would confirm the specs with BlackStealth to ensure compatibility, and not just order any 0-100psi off amazon for example.

Temp: Water oil temp sender, high match 140-280F, w/sealed plug 10' harness cutable | eBay
(Don’t forget the adapter you need to make for this to work)

Pressure: Universal 5 volt Electric Gauge Meter Sender Oil Fuel Pressure Sensor 100 psi | eBay

Below is an album with a tons of pictures of everything I described in this post.

 

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TIP: Under the floor there are several access plug grommets. This makes it easier to pass WBO2, Oil pressure / Oil temp sensor wire harness through, much easier than the crowded firewall access grommet.
 

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TIP: Under the floor there are several access plug grommets. This makes it easier to pass WBO2, Oil pressure / Oil temp sensor wire harness through, much easier than the crowded firewall access grommet.
Now that is an epic tip, a protip to end all protips.

Does anyone else feel naked without their virtual dashboard running?
 

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Discussion Starter · #80 ·
Now that is an epic tip, a protip to end all protips.

Does anyone else feel naked without their virtual dashboard running?
I wont even drive the car without torque up anymore lol. I need knock at a minumum in realtime, especially since everytime i drive im doing WOT pulls lol.
 
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