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

Got too cold here didn't hook up new Bluetooth adapter yet. Maybe tomorrow.

No the idol was pretty much the same after changing all the wires when it runs good it runs good and idles good it just does that taken off thing randomly I thought it was heat related but I don't think so much now because it did it at normal temperatures too and slightly higher temperatures but I don't think it's.
 
Drove it for over an hour and it ran good. Coming home, I got the High Idle. was able to do 60 MPH with cruise control off, and not touching the gas. Late shifts at light throttle along for the ride.
Maybe I do need a PCM. Can't get scanner to connect. Would like to look at my MAP and Vacuum next, but again, it won't connect.
Screenshot_20231103-121355.webp
 
mrbreezeet1 said:
Drove it for over an hour and it ran good. Coming home, I got the High Idle. was able to do 60 MPH with cruise control off, and not touching the gas. Late shifts at light throttle along for the ride.
Maybe I do need a PCM. Can't get scanner to connect. Would like to look at my MAP and Vacuum next, but again, it won't connect.
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hey @mrbreezeet1 thanks for the update.. ok so it wasn't the scanner after all, yup I wondered before if the other scanner wasn't defective and here we go. This new scanner cannot communicate to the ECU/ECM either! Then add in the three TPS wires have been replaced, along with two TPS sensors, and here we find this, no ECU communication.

Yup.. it's time to focus on the ECU/ECM, no doubt about it. I know you said you repaired your neighbors Acura before.. If it's possible open up your ECM, take a picture, post it and I'll see if I can spot any issues for you. And maybe someone else will see more than I will..but.. Maybe it's just a loose component you could re-solder, at least it's an attempt to save some $$$ before you have to buy another ECM. I did find a place that had a lifetime warranty on ECM's for your car.. I'll have to dig the link out, I didn't research if they're reputable. can always post here and see what everyone would recommend. If I remember they were like $194 and VIN was already uploaded to the ECM when you buy it.

This is good news! Finally getting some answers..
 
researcher said:
If it's possible open up your ECM, take a picture, post it and I'll see if I can spot any issues for you. And maybe someone else will see more than I will..but.. Maybe it's just a loose component you could re-solder, at least it's an attempt to save some $$$ before you have to buy another ECM
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I can do that! Maybe I have a big old resistor or a relay or two flopping around like his main relay! LMAO!
 
ECU/ECM/PCM/Computer...................... Pick a Name and go with it! Make up my mind will you all. (Not directed at you researcher} It's supposed to be a funny thing.
I'm glad I don't have that many names.
BTY, "Slow moving Train" is one of my nicknames!
 
I called them and asked if I could speak to a tech, N/A!
I asked her if the ECM's on a ~97 to 2003 GP were a common issue, she asked me if I was wanting to buy a ECM?
Then she asked me if I had taken it to a garage and diagnosed the issue. I then thanked her for her time.
 
I might try an ECM from LKQ.
$45.00, one year replacement or refund. 30 Day no questions asked $$$$ back return! Plus, they don't make a big deal about wanting the old ECM.
Almost can't beat that with a stick for a beater with a heater.
 
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mrbreezeet1 said:
ECU/ECM/PCM/Computer...................... Pick a Name and go with it! Make up my mind will you all. (Not directed at you researcher} It's supposed to be a funny thing.
I'm glad I don't have that many names.
BTY, "Slow moving Train" is one of my nicknames!
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well you might be a slow moving train, but you get there! :D and I'll just got with ECM, since that's what Pontiac calls it. but it's what I was thinking when I was typing that before! what the heck is the consensus!! Oh someone else called it the "brain".. lol.. I shouldn't encourage this behavior but ah what the heck! lol
 
mrbreezeet1 said:
I called them and asked if I could speak to a tech, N/A!
I asked her if the ECM's on a ~97 to 2003 GP were a common issue, she asked me if I was wanting to buy a ECM?
Then she asked me if I had taken it to a garage and diagnosed the issue. I then thanked her for her time.
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wow clueless too! the winning combination! No it wasn't flagship 1, they didn't really give me a good vibe reading their website. Found it, a place called Mintt, maybe see what everyone knows/thinks about this place.. here's a link to the Grand Prix 2001 ECM's they have

https://mintt.com/general-motors/pontiac-pcm/grand-prix-engine-control-module/?filters=years[2001]

mrbreezeet1 said:
This is of course, after looking at the board on my unit!
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Sure, taking a look first at yours.. Wouldn't that be something if stuff was hanging off of it like that Acura you repaired?! Honda quality?! just wow.. But LKQ, $45 isn't bad at all.. I love a good deal but the problem is.. with the age of yours and the failure it had, who knows if it isn't what happens when they all turn this age!? For example, the Camry valve cover gasket on this forum, they all die around 14-16 years old. Sure, a good life but it's consistent when they end up leaking, becoming brittle.
But if LKQ can get you on the road for another year.. There are arguments for both and against.. Just putting it out there..

It will be good to take a look at the pictures of your ECM's board..
 
researcher said:
wow clueless too! the winning combination! No it wasn't flagship 1, they didn't really give me a good vibe reading their website. Found it, a place called Mintt, maybe see what everyone knows/thinks about this place.. here's a link to the Grand Prix 2001 ECM's they have

https://mintt.com/general-motors/pontiac-pcm/grand-prix-engine-control-module/?filters=years[2001]


Sure, taking a look first at yours.. Wouldn't that be something if stuff was hanging off of it like that Acura you repaired?! Honda quality?! just wow.. But LKQ, $45 isn't bad at all.. I love a good deal but the problem is.. with the age of yours and the failure it had, who knows if it isn't what happens when they all turn this age!? For example, the Camry valve cover gasket on this forum, they all die around 14-16 years old. Sure, a good life but it's consistent when they end up leaking, becoming brittle.
But if LKQ can get you on the road for another year.. There are arguments for both and against.. Just putting it out there..

It will be good to take a look at the pictures of your ECM's board..
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Yeah! Might just be better off with a new one!
 
mrbreezeet1 said:
Well Heck, $145.00 isn't bad for a reman ECM! Or are they New? Too late to call now darn it.
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From what I saw reman/refurb, the new one was double the price at Rockauto. This needs the VIN programmed into it, so that's on top of the price + core + programming. Price+core was like $320 at Rockauto for brand new.
mrbreezeet1 said:
slow moving train won't have the board open today. I'm still goofing around up-stairs, :eek::sleep::geek:
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well there goes the day.. goofing around up-stairs!! lol
mrbreezeet1 said:
Still wanting to apply the KISS system, Will be checking fuse's next too!
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yup check the fuses, but when ya get around to it, be interesting to see the physical insides of the ECM.
 
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