P0121 TPS pending code and losing 12V low reference ground to ECM. lntermittent high ldle and late shift issue.

A bit OT, but I'd like to try the Torque Pro or other possible scanner apps for windows in my laptop.
I's like wired, Ver's bluetooth though, anyone use something like this?
But this one says XP, 7, and 8 I think, but not windows 10. But maybe it's just an older ad.
Do you all think this would work on 10?
https://www.amazon.com/dp/B0B6PXHLC...2663G49D&psc=1&ref_=list_c_wl_lv_ov_lig_dp_it
Speaking of scanner apps, is there a Tech II Clone type of deal I could install on a laptop?

1698429611942.webp
 
mrbreezeet1 said:
Oh, cool! I did not know that about the ECM not allowing communication.
I only have the one car, but I guess I can "borrow" a neighbor's car.



Thanks Brother!
Click to expand...
No problem! Yup, the OBD2 port is a data connector directly to the ECU/ECM. I always thought it was hilarious that they had trouble codes for an ECM.. But where does the command come from for that code? um.. the ECM! But the ECM is dying!! How can it inform on itself it isn't working? lol.. dog.. chasing..its tail.. lol

Anyway, the odd live data you're getting could be the ECM.. Glad you can "borrow" a neighbors car just to make sure your scanner is working.

ECM's dying do happen, and the problem with 2001 is that was the era of the bad capacitors. The story goes that Nichcon (well respected capacitor manufacturer) suspected corporate espionage. So they left a "recipe" of their awesome capacitor out for someone to steal. Only problem was, they left out one ingredient! lol.. When they stole it, sold it to the competitors, bam! Bad caps dying all over the place. Now they could point to who stole their recipe! What did this result in? Bad caps all over the market! what year was this occuring? 2001 until about 2004 from what I remember. The cap problem was so costly it took down some motherboard (PC, computer) manufacturers! Like ABIT. I know that it did affect even the Honda's of the era too. Did it get to GM? Who knows.. but that could be the intermittent problem you're seeing on your ECM!

Only way to truly know is to open up and look at the caps (they look like small pop cans) and see if they're bulging or leaking electrolytic fluid. They're basically small batteries that hold a charge temporarily. I know this is probably above what you're used to, but just helping you be informed. A new computer would have new caps..

I tell you this with my background in electronics/computers so you can understand the bigger picture of what might be going on if the ECM is bad and why. It could be as easy as removing the old caps and soldering in new ones. I did that on my Civic. but in the end a new ECU was needed. Sometimes you can only repair an old electronic device so much before it's just done for.

If you do have to get a new ECM/ECU then I'd suggest doing some research for a company that stands behind what they've repaired. You can buy a new one from GM, rockauto has it for $232, but then it requires someone to program it.. more $$$.. Might be better to buy one already programmed for your vehicle. Might post up on here to see who's reputable for a repaired ECM. if you end up going that way.

hope that helps.
 
mrbreezeet1 said:
A bit OT, but I'd like to try the Torque Pro or other possible scanner apps for windows in my laptop.
I's like wired, Ver's bluetooth though, anyone use something like this?
But this one says XP, 7, and 8 I think, but not windows 10. But maybe it's just an older ad.
Do you all think this would work on 10?
https://www.amazon.com/dp/B0B6PXHLC...2663G49D&psc=1&ref_=list_c_wl_lv_ov_lig_dp_it
Speaking of scanner apps, is there a Tech II Clone type of deal I could install on a laptop?

View attachment 185435
Click to expand...
I haven't dug too deep into these, someone else might know..
 
researcher said:
No problem! Yup, the OBD2 port is a data connector directly to the ECU/ECM. I always thought it was hilarious that they had trouble codes for an ECM.. But where does the command come from for that code? um.. the ECM! But the ECM is dying!! How can it inform on itself it isn't working? lol.. dog.. chasing..its tail.. lol
Click to expand...
It is! That's funny!
researcher said:
Anyway, the odd live data you're getting could be the ECM.. Glad you can "borrow" a neighbors car just to make sure your scanner is working.

ECM's dying do happen, and the problem with 2001 is that was the era of the bad capacitors. The story goes that Nichcon (well respected capacitor manufacturer) suspected corporate espionage. So they left a "recipe" of their awesome capacitor out for someone to steal. Only problem was, they left out one ingredient! lol.. When they stole it, sold it to the competitors, bam! Bad caps dying all over the place. Now they could point to who stole their recipe! What did this result in? Bad caps all over the market! what year was this occuring? 2001 until about 2004 from what I remember. The cap problem was so costly it took down some motherboard (PC, computer) manufacturers! Like ABIT. I know that it did affect even the Honda's of the era too. Did it get to GM? Who knows.. but that could be the intermittent problem you're seeing on your ECM!

Only way to truly know is to open up and look at the caps (they look like small pop cans) and see if they're bulging or leaking electrolytic fluid. They're basically small batteries that hold a charge temporarily. I know this is probably above what you're used to, but just helping you be informed. A new computer would have new caps..

I tell you this with my background in electronics/computers so you can understand the bigger picture of what might be going on if the ECM is bad and why. It could be as easy as removing the old caps and soldering in new ones. I did that on my Civic. but in the end a new ECU was needed. Sometimes you can only repair an old electronic device so much before it's just done for.

If you do have to get a new ECM/ECU then I'd suggest doing some research for a company that stands behind what they've repaired. You can buy a new one from GM, rockauto has it for $232, but then it requires someone to program it.. more $$$.. Might be better to buy one already programmed for your vehicle. Might post up on here to see who's reputable for a repaired ECM. if you end up going that way.

hope that helps.
Click to expand...
No, I've opened and repaired a few boards, bad solder, bad relay, burnt part of the P/C {my Dumb @$$ fault}
Spilled coffee on my digital piano {my Dumb @$$ fault again!}
Not all experienced like you, or like my one school mate is today, but I maybe know enough to "not be dangerous" lol
Thanks! I'll keep the thread updated.
Did you see my neighbors main fuel pump relay from his Accura?
 
Last edited:
mrbreezeet1 said:
It is! That's funny!

No, I've opened and repaired a few boards, bad solder, bad relay, burnt part of the P/C {my Dumb @$$ fault}
Spilled coffee on my digital piano {my Dumb @$$ fault again!}
Not all experienced like you, or like my one school mate is today, but I maybe know enough to "not be dangerous" lol
Thanks! I'll keep the thread updated.
Did you see my neighbors main fuel pump relay from his Accura?
Click to expand...
oh duh,... that's right, I do remember.. ok then maybe if the ECM is bad, crack it open and see if any of the caps are bad. Could save some $$$ right there. ya that was hilarious that video showing how all the components on that relay board were moving! wow..
 
researcher said:
oh duh,... that's right, I do remember.. ok then maybe if the ECM is bad, crack it open and see if any of the caps are bad. Could save some $$$ right there. ya that was hilarious that video showing how all the components on that relay board were moving! wow..
Click to expand...
LMAO!
Is this here good wire for my application? Good company? Reviews were good.

BINNEKER 22 Gauge Silicone Wire Kit 6 Color Red Black White Blue Green Yellow (6m/19.7ft Each) High Resistant 200 deg C 600V Electronic Wire 22 AWG Stranded Wire 60 Strands Tinned Copper Wire​


https://www.amazon.com/dp/B07WYYDBZ...ZM43YV8N&psc=1&ref_=list_c_wl_lv_ov_lig_dp_it
 
mrbreezeet1 said:
LMAO!
Is this here good wire for my application? Good company? Reviews were good.

BINNEKER 22 Gauge Silicone Wire Kit 6 Color Red Black White Blue Green Yellow (6m/19.7ft Each) High Resistant 200 deg C 600V Electronic Wire 22 AWG Stranded Wire 60 Strands Tinned Copper Wire​


https://www.amazon.com/dp/B07WYYDBZ...ZM43YV8N&psc=1&ref_=list_c_wl_lv_ov_lig_dp_it
Click to expand...
I know one thing! It doesn't splice worth a darn! Try to twist up a western union type of splice, or say the heck with that, and just twist a pigtail type splice, and look at it wrong, and it untwists! Guess what is probably going back to Amazon next~
 
mrbreezeet1 said:
I know one thing! It doesn't splice worth a darn! Try to twist up a western union type of splice, or say the heck with that, and just twist a pigtail type splice, and look at it wrong, and it untwists! Guess what is probably going back to Amazon next~
Click to expand...
lol.. wow.. I'm wondering if it's the silicone jacket that's causing it to do that, or the wire just sucks! Let me see.. I can guess this is going back to amazon!?

I did get some wiring for wiring up some speakers in the car, it's 20 gauge, and the quality is really good, if you needed something else.. here's a link

https://www.amazon.com/AOTORUA-Elec..._1_16?keywords=AOTORUA&qid=1698449304&sr=8-16

I know it has a PVC jacket but not intending for the car to light on fire any time soon! lol..

I did find some silicone jacket assortment in stranded and solid wire, not sure if this is just a re-brand of what you got? here's a link
https://www.amazon.com/Electrical-c...9cc-8d87-b909f19095c5&pd_rd_i=B083DNGSPV&th=1
 
mrbreezeet1 said:
Thanks, Yeah, I sent it back.
Thanks, I'll check the links, I have some here that will work, but my OCD wanted the same color coded wires.
The seller of the USB OBD 2 port for windows says it will work on windows 10.

https://www.amazon.com/AOTORUA-Elec..._1_16?keywords=AOTORUA&qid=1698449304&sr=8-16
Looks like nice wire!
Click to expand...
glad to hear the usb obd2 port works for win 10!

ya figured if you wanted some decent wire just recommend what I already ordered.. thanks!
 
Last edited:
mrbreezeet1 said:
This might me nice too, don't Y'a think, as long as it splice's OK, wouldn't need split loom either, just piggyback it to the under hood harness?
https://www.amazon.com/FIRMERST-Con...9b-a1cd-b1d2afc8754a&pd_rd_i=B0BZ4QRTW1&psc=1

{To word it more properly actually it's the signal wire *from the TPS* *To the ECM* Terminal C @ TPS to ECM connector C2 Pin # 66}

View attachment 185597
Click to expand...
not a bad idea!! (y) that way no more extra wires, which were only for testing anyway.. good way to make it clean!!
 
researcher said:
hey @mrbreezeet1 .. how is the testing going? any update? I know I saw you were looking at a different scan tool on the other thread..
Click to expand...
I just have a inexpensive Bluetooth dongle coming tomorrow. And the speaker wire.
I have all 3 wires replaced temporarily for now to see what happens.
Haven't really driven it enough since I replaced this blue signal wire.
Since replacing the blue signal wire it seems to be working okay but then again the issue has been intermittent.
.
 
mrbreezeet1 said:
I just have a inexpensive Bluetooth dongle coming tomorrow. And the speaker wire.
I have all 3 wires replaced temporarily for now to see what happens.
Haven't really driven it enough since I replaced this blue signal wire.
Since replacing the blue signal wire it seems to be working okay but then again the issue has been intermittent.
.
Click to expand...
Hey, thanks for the update!! be interesting to see how that new scanner/dongle works..
ok so all three wires have been replaced, the blue signal might have been bad, but you're right, since it's intermittent just have to wait to see if it's a permanent fix. At least all of this is moving in the right/positive direction! that's good news..
 
researcher said:
Hey, thanks for the update!! be interesting to see how that new scanner/dongle works..
ok so all three wires have been replaced, the blue signal might have been bad, but you're right, since it's intermittent just have to wait to see if it's a permanent fix. At least all of this is moving in the right/positive direction! that's good news..
Click to expand...
Thanks for the support!

You would be the one to ask!

Now, I have replaced the TPS.
Unlikely my Old TPS was bad, and the new one too!

When the system is behaving itself, I have a nice clean sweep, In as well as Torque Pro can pick it up at least, from 0% at idle, to 100% at WOT.
Now, even though the DTC P0121 points the finger right a "Circuit A",
the way I am looking at this is this, looking at the schematic, to me at least, it's conceivable that an intermittent fault, be it an open, be it a short to ground, be it a short to 12 volts, in ANY ONE of those three wires................... In my mind says the P0121 could conceivably be set by any one of those wires having a fault. My thinking is that they are all a "Part of circuit A at one time or another!
Unless I'm seeing it wrong. After all in real life, DCT's are a guide, not a diffeniate "OK, replace this sensor, or replace this wire, or replace vacuum hose with big old vacuum leak, causing bank one lean condition!!

Now, having said all that, the first value I want to look at on the scanner, (so through the ECM's eyes} when I get the OBD 2 dongle is my vacuum! I did notice before I could no longer connect, that is was quite low. And it WAS NOT low when I first started trying to check all this! So maybe a vacuum leak, or electrical issue WRT the MAP sensor throwing a monkey wrench at this.
 
I gave myself a throttle position sensor circuit quiz.
I got them all right.
I guess I should have them memorized by now 😂😆🤣
IMG_20231101_174711599.webp
 
mrbreezeet1 said:
Thanks for the support!

You would be the one to ask!

Now, I have replaced the TPS.
Unlikely my Old TPS was bad, and the new one too!

When the system is behaving itself, I have a nice clean sweep, In as well as Torque Pro can pick it up at least, from 0% at idle, to 100% at WOT.
Now, even though the DTC P0121 points the finger right a "Circuit A",
the way I am looking at this is this, looking at the schematic, to me at least, it's conceivable that an intermittent fault, be it an open, be it a short to ground, be it a short to 12 volts, in ANY ONE of those three wires................... In my mind says the P0121 could conceivably be set by any one of those wires having a fault. My thinking is that they are all a "Part of circuit A at one time or another!
Unless I'm seeing it wrong. After all in real life, DCT's are a guide, not a diffeniate "OK, replace this sensor, or replace this wire, or replace vacuum hose with big old vacuum leak, causing bank one lean condition!!

Now, having said all that, the first value I want to look at on the scanner, (so through the ECM's eyes} when I get the OBD 2 dongle is my vacuum! I did notice before I could no longer connect, that is was quite low. And it WAS NOT low when I first started trying to check all this! So maybe a vacuum leak, or electrical issue WRT the MAP sensor throwing a monkey wrench at this.
Click to expand...
thanks for the compliment, I appreciate it!

Ok let's say that it is a short to ground, the thinking would be that the wire from the TPS could be doing that.. but.. You've replaced the three wires with new, not likely that would be shorting out now. It could have before if there was a break in the wire under the insulation. I had that happen on the old wiring in the Civic. But yes, you're right that the DTC could be a short, or it was. Yep the DTC's are sometimes an exact answer such as "this component just died" and other times it's a symptom of something else having a problem. Like you said a guide.

Be interesting to see what the new OBD scanner tells you.. I didn't scan the pages in this post but how was the idle once you hooked up the three new wires from the TPS to the ECM? Did it get better? I saw in the other post that after the engine was warmed up, then it had a higher idle problem.. Did that stop after the wiring was re-done? I know you said you haven't driven it much, but I gotta ask.

That way, if the TPS wiring was replaced and the idle improved you're on to something. Vacuum lines do crack and it could affect the idle when it does and it doesn't hurt to physically check them. Otherwise you'd need a vacuum hand pump/gauge to see if they're bad.. Cheaper to just check the hoses with bright flashlight.. heck you know the drill! :geek:

And you're right, both TPS being bad? in the same way? Hardly likely.. Anything is possible..I keep thinking it's the wiring but hey I could be wrong! But that's how it feels..

also.. yep I was looking up the DTC code and it could combine with the MAP/MAF to cause this issue.. you're right. ok.. anything else is speculation right now.. be good to see what the new scanner tells you and go from there..
 
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