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Discussion Starter · #81 ·
Been a while since posting an update with my car, I was waiting on the Chrome ECU, which arrived yesterday!!:D

So, getting right to it;
Installed, car fired up and ran fine... I was hopeful but honestly still preparing for the worst ie no change... took it for a spin (forgot to hit 'start logging' so didn't capture the first run in a log). ANyway, it ran great WITHOUT HESITATION/BUCKING!!! and no engine codes for a while...
(minor points about quality control of the Chrome unit itself, but I'll mention that in another post at some point)

That being said I only drove it for about 20 min in town, and Torque Pro did give me pending fault notification... p0120. I partially checked my TPS already during my troubleshooting and it seemed ok, but had erroneous readings in the log (pre Chrome). I guess I'll be doing a more thorough testing of the TPS when I get the chance, or looking into other things. I drove the car one other time last night, about 20 min again and got a log which I'll upload soon. Again, drove and accelerated smooth, no issues (didn't get the pending engine fault this time). The log shows Throttle Postion drop off to 0, but seems to be when I'm coasting down (foot off the gas), so not sure if that's normal or not to have readings of zero during that time?
Funny I drove the car home from Iowa City 1200km (750miles) when I bought it, even with the hesitation happening back then, with I guess a sort of blind confidence... now I'm tentative going on short drives, always looking for where I may have to pull over so I'm not stalled out in the middle of trafic lol :S.
 

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Discussion Starter · #83 ·
I'll still be doing a bunch more to confirm my main issues are actually resolved and/or what still needs to be done.. but I'm so happy that the new ECU definitely does seem to be helping to fix my hesitation/stalling issues (if not completely!). Time/further testing will tell!
 

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Discussion Starter · #84 ·
Just to update this thread... I started a separate thread because the Jester/Chrome ECU I got had an issue. Flawed unit, likely a broken solder joint. Anyway, returned that unit and got a replacement which seems to be good this time knock on wood and I'm currently very happy to be over all of the issues surrounding my ECU!

I have driven 2 or 3 times, but didn't bother logging yet. It turns out that I still have an occasional hesitation (so far seemed like mostly in 2nd gear when I was really stepping on it/accelerating near WOT). Overall driving and sounding great now, and has accelerated perfectly smoothly MOST of the time, just occasionally I'll have to ease off for a split second. I'm leaning towards injectors to solve this last bit but we'll see. I don't want to go spending money and time replacing parts unnecessarily now so I'm going to drive it a bit more and log a few times to be more sure.
Could still any of the early mentioned ideas in this thread, or maybe just the car getting used to the new ECU/mappings? (doubt it but what do I know).

For now, I'm happy to have 'er back on the road!
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I'm wondering if it's possible that the ECU went bad from an issue in the electronic or bad production.
 

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Discussion Starter · #86 ·
I'm wondering if it's possible that the ECU went bad from an issue in the electronic or bad production.
don't really think it could be anything but the production of the ECU.. if you look in the dedicated thread to the issue I showed that it only happened with the Chrome ECU (first one), and not my OEM original ECU. I posted a video showing this as well. IMO this essentially ruled out a wiring/separate electronic problem. Of course I was still slightly hesitant/worried, but the new Chrome ECU seems to be working great.
Don't want to knock Jester/Chrome ECUs, because trust me I'm super happy that Adam took the time to makes these.. and I love that we have them as a great option for piece of mind and future tuning potential. I initially got one that had a bad connection, shit happens, fixed now.
 

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Discussion Starter · #87 ·
So my car is running well enough to drive and the ECU fixed a bunch of problems (doesn't stall out/die anymore, stock boost gauge works normally again, cruise control works again, and overall runs much smoother), BUT:
Still having some hesitation/bucking (not always, but sometimes, and only when accelerating). Took a while to update this thread because I had to sort out a few things with my scantool and CANBUS device and I finally got the cables setup properly and the correct versions flashed on the devices (thankyou Antero/BlackStealth).
Codes that I now get from the scantool:

Code 25 - Barometric pressure Sensor
Code 62 - VICS MPS circuit

Doing some research on those codes now... both to do with airflow and guess that could makes sense with my hesitation/bucking. Anyway I'm doing some more reading on the subject of each first but figured I'd update the thread. I have some time set for working on the car this weekend so hoping to get to the bottom of this. I actually hadn't gotten around to doing my plugs/wires yet so that was already in the plans.
 

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Not sure about 62, but the only barometric pressure sensor i am aware of is on the MAF (assuming you have stock). You can log/view barometric pressure with Torque through the CANBUS device. It's basically ambient atmospheric pressure. If its reading wrong it could be feeding the ECU incorrect air density info.
 

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VICS circuit should only apply to non-turbo ECUs. You should be getting only OBD2 style compliant error codes with a Chrome ECU, like P0120 or something. Choose the 96-99 USA scan on the touchscreen, so it goes into OBD2 mode to fetch the error codes if there any.
 

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Discussion Starter · #90 ·
slow on the update, (I was away on some family vacay for a bit). Thanks for the replies.
With the proper scantool settings as per BlackStealth's tips, I'm getting P0120: TPS sensor.
I'll attach the recent log I just took doing a couple of WOT pulls to try and get the best log data.. I didn't have any knock detected on previous logs, but this one shows a few:S.. really hope it's not that bad but I'm still very much just trying to learn/decipher this stuff.
With the TPS code, and looking at the log I think I may try swapping my TPS from my '93 NA (still going to confirm but I thiiink that is a part I can swap) and see if that does anything.
Any other observations from my log here would be greatly appreciated!
Thanks.
 

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I dont see any out of spec TPS values in the log? It looks like its going from about 13 to high 90s? The main concern is if it goes to zero (or more generally, less than 10 i believe).

What issues/symptoms are you having?

Also, for the datalogs, you might want to try giving datazap a shot for uploading them. I use it extensively for datalogging on my BMW and its the preferred platform for that. You basically just upload the CSV and it does the graphing for you... only limitation is X axis is always time, but its free and easy to upload/share datalogs and easily look at different parameters. I've never seen it used on this platform but heres an example of one of my 335i logs if you want to see what it looks like: datazap.me | thejeremyman9 | 3x 4th E20 2+

If you are doing tuning you might still use excel so you can plot AFR versus RPM for example (that's how i did it), but datazap works great for just going through logs in general.
 

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Discussion Starter · #92 ·
hm that datazap looks pretty neat, I'll definitely try it out!
Still same hesitation slight bucking etc at times (not always) if I accelerate hard.
Looking to the TPS first now because that's the code i get from the scanner and figure it couldn't hurt to swap and see what happens. Any idea how bad is it that there were a few knock counts on this log? only a couple of times, max of 4 counts, but still something I don't like to see.
 

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Did it buck during that log?

It's hard to say for certain but it looks like it did pull timing when you had that knock. Logging boost would be helpful to interpret when the knock is occurring as well.
 

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I once had a bad TPS sensor on my car. It showed it was above 10% most of the time, but every once in a while it would blip into the 0% territory and trigger a TPS error code.
 

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Discussion Starter · #95 ·
Did it buck during that log?

It's hard to say for certain but it looks like it did pull timing when you had that knock. Logging boost would be helpful to interpret when the knock is occurring as well.
Yes it did definitely hesitate/buck in that log during each hard acceleration, that's specifically what I'm trying to capture in the log and figure out...

I once had a bad TPS sensor on my car. It showed it was above 10% most of the time, but every once in a while it would blip into the 0% territory and trigger a TPS error code.
did you also have hesitation during acceleration that was solved by this? or anything noticeable in the drive?

I haven't had time to work on the car/test anything yet, hoping within the next week here I'll make some time to at least try the TPS sensor swap.
 

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I'm still here as well. Same issues, checked a bunch of things. Question, were both (Brown and black) stock IAC/ISC metal? I just happened to notice a forum where someone said plastic non-oem ones can't handle heat and wear out fast. I'll look for a recent log to upload. All I do, when I get time, is troubleshoot things I haven't before and drive it around the block hoping I don't get hesitation or idle drop.
 

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See my previous posts in this discussion. After it warms up and I shift into neutral and come to a stop rpms drop below idle. Also, hesitation. ISC passed multimeter tests. Asked above if both brown and black isc were metal as I have a plastic black one installed new 5000 miles ago and was told that the heat can destroy them quicker.
 
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