Thread: Need serious advice about my nightmare car

Background:

Alright, so I just wanna chronicle my whole experience with this car for anyone who might care, if you don't feel like reading but still wanna help with my questions they're at the bottom.

Here's the story. This is my first car, I bought it around 3 years ago because I liked the color. It's orange and black, and the paint job is pretty much the only thing that has ever been good about it. The guy I bought it from lied his ass off, although I had no idea at the time. The body is from a 97 gt, but the dude blew the original motor and swapped in what he told me was a 2002 gtp engine. The crazy rats nest of wiring under the pcm (which was just sitting in the engine bay, no air filter box or anything) should've been enough to make me reconsider buying it, but not knowing anything I assumed whatever was wrong with it would be an easy enough fix.

The check engine light was on, but when I asked why the guy plugged in his OBDII tester and showed me that the code was for the engine coolant temp sensor, assuring me it was easy to replace. So I bought it. The car started, ran and drove fine on the half hour drive back to my house. Once I got it back I immediately realized something wasn't right because of the crazy amount of heat pouring out of the engine compartment.

I found the ECT sensor, and the previous owner had unplugged it. I plugged it back in and the temp gauge read extremely hot. My friend, who has a lot more experience with cars, suggested it might have been a cracked exhaust manifold. I got the guy I'd just bought it from on the phone, I was extremely angry and yelling at him, he finally admitted to me that the real problem was the radiator fans. They botched the wiring job and the fans don't kick on, ever.

I drove the car for a while, like 3 months, by jumping the two fan relay ports in the fuse box with a busted apart relay that I'd stuck a paperclip in. If it wasn't my car it would've been hilarious, it was to everyone else. I had to pop the hood every time I drove and plug the jumped relays in so the fans would stay on. Even still, the car overheated sometimes and I had to drive with the heat on when it was hot outside.

On 90 degree days It was probably 110 in my car. After three months of that, I finally got tired of it and gave up on the idea actually being able to fix the problem. My friend and I spliced in switches, so my fans are run off the battery and I've got switches to control them right in front of the shifter. That made driving a lot easier, but the car has been slowly breaking down on me. Oh, and the second day I had the thing my friend's sister, now my girlfriend, busted the already half-broken rear driver's side door handle all the way off. I have a new handle, but the paint is some custom color and although the previous owner said he had leftover paint, I'm not exactly on good terms with him after some angry drunken phone calls I made.

The problems didn't end there though. I don't remember exactly when, but about a year after I bought it the key stopped coming out of the ignition, I use the release to get it out, and the shifter only comes out of park using the release too. I had to replace a rear trailing arm that broke on me, new ball joints, finding that my ABS sensor had been cut off altogether, and deal with a trans cooler line popping off and basically emptying all the fluid out of the trans all over the bottom of my engine while I was 45 minutes from my house.

I took it to my buddy's shop a month ago after it started shifting really oddly and idling badly, like it was gonna die. It has been over revving and slamming into gear or missing shift points altogether. When I plugged in the shop's nice big Snap-on scanner, my car was throwing 9 unique codes, which brings me to...


The Problems
CODES:
P0122 - TP or APP Sensor 1 circuit short/low
P0141 - O2 Heater Circuit Bank 1 Sensor 2
P0452 - EVAP Pressure Sensor Signal low/Short
P0719 - TCC/Brake Switch 'B' Circuit signal low/short
P1122 - TP Circuit Intermittent low voltage
P1651 - Fan Circuit Relay 1 or QDM 'B' Fault
P1652
P1653
P1665 - EVAP Solenoid Control Circuit
P1676 - EVAP Purge Driver Circuit
P1811 - Maximum adapt 3 long shift

For anyone who didn't feel like reading the depressing short story about the hot garbage that is my car, I have a 97 Grand Prix with a 98 (I think) supercharged 3800 series II

My Questions:
Question 1: So I want to get an entirely new engine wire harness and possibly PCM, the harness that's in my car right now is spliced like a bad joke. There are two tranny plugs, disconnected wires leading nowhere, you get the point. The PCM is for a 1998, even though I was told the engine was an 02. Where are the id numbers/date stamp on my engine block so I can determine what year the engine actually is, or else how do I figure this out? What harnesses will fit correctly on a 98 engine and PCM? Can I use anything from 97-02? Should I get a new PCM as well? and lastly will i need to pull the engine to swap harnesses? I believe this may fix a few of my problems, the fans, O2 sensor and TCC switch I hope.

Question 2: I got two used floor shifter assemblies from the junkyard and plugged them both in, with no success. The car still doesn't shift out of park without pressing the release. I know that the key being stuck in the ignition and the car not shifting out of park are both related, what could the problem be if it isn't the BTIS solenoid in the shifter assembly? Could it be a solenoid in the steering column?

Question 3: Not really a question, but any advice about what could be wrong with my EVAP system/what to look for or replace first would be appreciated because I know very little about EVAP and it's killing my gas mileage.

I drive this car every day. I was an idiot to buy it in the first place, but I'm stuck with it now. I'm broke and in college, and the only way to sell the thing without taking a big loss (and having no money for a new car) would be to lie my ass off and hope the prospective buyer is as dumb as I was. I decided against doing that, so now I'm stuck with this thing and limited money to fix it with. Any advice, help, or condolences would be greatly appreciated, and thanks a ton in advance to everyone who reads and replies.

Heh ya lost me at Orange and Black but ill give ya a bump to try and get ya a response bud! Good luck!

Originally Posted by kwk6564

Background:

Alright, so I just wanna chronicle my whole experience with this car for anyone who might care, if you don't feel like reading but still wanna help with my questions they're at the bottom.

Here's the story. This is my first car, I bought it around 3 years ago because I liked the color. It's orange and black, and the paint job is pretty much the only thing that has ever been good about it. The guy I bought it from lied his ass off, although I had no idea at the time. The body is from a 97 gt, but the dude blew the original motor and swapped in what he told me was a 2002 gtp engine. The crazy rats nest of wiring under the pcm (which was just sitting in the engine bay, no air filter box or anything) should've been enough to make me reconsider buying it, but not knowing anything I assumed whatever was wrong with it would be an easy enough fix.

The check engine light was on, but when I asked why the guy plugged in his OBDII tester and showed me that the code was for the engine coolant temp sensor, assuring me it was easy to replace. So I bought it. The car started, ran and drove fine on the half hour drive back to my house. Once I got it back I immediately realized something wasn't right because of the crazy amount of heat pouring out of the engine compartment.

I found the ECT sensor, and the previous owner had unplugged it. I plugged it back in and the temp gauge read extremely hot. My friend, who has a lot more experience with cars, suggested it might have been a cracked exhaust manifold. I got the guy I'd just bought it from on the phone, I was extremely angry and yelling at him, he finally admitted to me that the real problem was the radiator fans. They botched the wiring job and the fans don't kick on, ever.

I drove the car for a while, like 3 months, by jumping the two fan relay ports in the fuse box with a busted apart relay that I'd stuck a paperclip in. If it wasn't my car it would've been hilarious, it was to everyone else. I had to pop the hood every time I drove and plug the jumped relays in so the fans would stay on. Even still, the car overheated sometimes and I had to drive with the heat on when it was hot outside.

On 90 degree days It was probably 110 in my car. After three months of that, I finally got tired of it and gave up on the idea actually being able to fix the problem. My friend and I spliced in switches, so my fans are run off the battery and I've got switches to control them right in front of the shifter. That made driving a lot easier, but the car has been slowly breaking down on me. Oh, and the second day I had the thing my friend's sister, now my girlfriend, busted the already half-broken rear driver's side door handle all the way off. I have a new handle, but the paint is some custom color and although the previous owner said he had leftover paint, I'm not exactly on good terms with him after some angry drunken phone calls I made.

The problems didn't end there though. I don't remember exactly when, but about a year after I bought it the key stopped coming out of the ignition, I use the release to get it out, and the shifter only comes out of park using the release too. I had to replace a rear trailing arm that broke on me, new ball joints, finding that my ABS sensor had been cut off altogether, and deal with a trans cooler line popping off and basically emptying all the fluid out of the trans all over the bottom of my engine while I was 45 minutes from my house.

I took it to my buddy's shop a month ago after it started shifting really oddly and idling badly, like it was gonna die. It has been over revving and slamming into gear or missing shift points altogether. When I plugged in the shop's nice big Snap-on scanner, my car was throwing 9 unique codes, which brings me to...


The Problems
CODES:
P0122 - TP or APP Sensor 1 circuit short/low
P0141 - O2 Heater Circuit Bank 1 Sensor 2
P0452 - EVAP Pressure Sensor Signal low/Short
P0719 - TCC/Brake Switch 'B' Circuit signal low/short
P1122 - TP Circuit Intermittent low voltage
P1651 - Fan Circuit Relay 1 or QDM 'B' Fault
P1652
P1653
P1665 - EVAP Solenoid Control Circuit
P1676 - EVAP Purge Driver Circuit
P1811 - Maximum adapt 3 long shift

For anyone who didn't feel like reading the depressing short story about the hot garbage that is my car, I have a 97 Grand Prix with a 98 (I think) supercharged 3800 series II

My Questions:
Question 1: So I want to get an entirely new engine wire harness and possibly PCM, the harness that's in my car right now is spliced like a bad joke. There are two tranny plugs, disconnected wires leading nowhere, you get the point. The PCM is for a 1998, even though I was told the engine was an 02. Where are the id numbers/date stamp on my engine block so I can determine what year the engine actually is, or else how do I figure this out? What harnesses will fit correctly on a 98 engine and PCM? Can I use anything from 97-02? Should I get a new PCM as well? and lastly will i need to pull the engine to swap harnesses? I believe this may fix a few of my problems, the fans, O2 sensor and TCC switch I hope.

Question 2: I got two used floor shifter assemblies from the junkyard and plugged them both in, with no success. The car still doesn't shift out of park without pressing the release. I know that the key being stuck in the ignition and the car not shifting out of park are both related, what could the problem be if it isn't the BTIS solenoid in the shifter assembly? Could it be a solenoid in the steering column?

Question 3: Not really a question, but any advice about what could be wrong with my EVAP system/what to look for or replace first would be appreciated because I know very little about EVAP and it's killing my gas mileage.

I drive this car every day. I was an idiot to buy it in the first place, but I'm stuck with it now. I'm broke and in college, and the only way to sell the thing without taking a big loss (and having no money for a new car) would be to lie my ass off and hope the prospective buyer is as dumb as I was. I decided against doing that, so now I'm stuck with this thing and limited money to fix it with. Any advice, help, or condolences would be greatly appreciated, and thanks a ton in advance to everyone who reads and replies.

Sorry.

But the way i'd fix this car involves a rag in the gas filler soaked in kerosene and a zippo.

Originally Posted by kwk6564

My Questions:
Question 1: So I want to get an entirely new engine wire harness and possibly PCM, the harness that's in my car right now is spliced like a bad joke. There are two tranny plugs, disconnected wires leading nowhere, you get the point. The PCM is for a 1998, even though I was told the engine was an 02. Where are the id numbers/date stamp on my engine block so I can determine what year the engine actually is, or else how do I figure this out? What harnesses will fit correctly on a 98 engine and PCM? Can I use anything from 97-02? Should I get a new PCM as well? and lastly will i need to pull the engine to swap harnesses? I believe this may fix a few of my problems, the fans, O2 sensor and TCC switch I hope.

Question 2: I got two used floor shifter assemblies from the junkyard and plugged them both in, with no success. The car still doesn't shift out of park without pressing the release. I know that the key being stuck in the ignition and the car not shifting out of park are both related, what could the problem be if it isn't the BTIS solenoid in the shifter assembly? Could it be a solenoid in the steering column?

Question 3: Not really a question, but any advice about what could be wrong with my EVAP system/what to look for or replace first would be appreciated because I know very little about EVAP and it's killing my gas mileage.

I drive this car every day. I was an idiot to buy it in the first place, but I'm stuck with it now. I'm broke and in college, and the only way to sell the thing without taking a big loss (and having no money for a new car) would be to lie my ass off and hope the prospective buyer is as dumb as I was. I decided against doing that, so now I'm stuck with this thing and limited money to fix it with. Any advice, help, or condolences would be greatly appreciated, and thanks a ton in advance to everyone who reads and replies.

#1: Many people experience fan issues and it ends up being corrosion etc in the wiring harness. If your car is technically a 97 model year according to the VIN, then get a 97 GTP harness. If it's a 98 VIN, get a 98 harness. The modifications to run a SC engine in an NA car are very small. Sounds like your car started life as an NA car and had a entire SC'd engine/transmission put in. That explains the second transmission plug. As for telling on the engine, there is no marking etc that tells you the year. Your best bet would be to use the tag on the transmission for year identification. The tag is located on the back passenger side of the transmission. You can run any 97-02 engine/trans combo on any 97-02 pcm, however your interior electronics etc will be happiest if you run on the year harness/pcm for the correct year of the vehicle. (maf table being the biggest change). You do not pull the motor to swap a harness, that would be the hardest way possible to change the harness. Do it with everything in the engine bay and don't worry.. it's not tough.

2. Problem could be as simple as a blown fuse. I'd look for the power source and ensure it's not bad. I recently did a 5 minute solder job for a local to fix this issue.

3. Depending on the year your pcm is programmed for ...could be the cause. 97 had a evap soleniod and purge valve that were seperate. 98+ had them combined and other years used different parts. Let's start on the right wiring and work out way back to it.


Likely your P0122 TPS issue is causing your trans to shift oddly and messed up
Likely your P0141 O2 Heater circuit is causing the poor fuel mileage because the O2 isn't heating up fast.
Sounds like you do have either a bad fuse or a wiring nightmare. Please post a couple pictures of this wiring.

Just walk away and call it a loss and chalk it up to a learning experience.

Originally Posted by 99XC600

Just walk away and call it a loss and chalk it up to a learning experience.

I'll buy your car from you when a fuse blows... for $5

Geez. A couple hours of work and likely the car is fine. Problem is most likely the guy before him.

Don't give up on the car. It's at least worth trying to fix. I bought a fiero that somebody tried to swap out the 4 cyl for a v6 and did a nightmare job on the wiring harness. With some time, patience and research you'll be able to figure it out.

How are the rockers, fenders and strut towers? If good, start trouble shooting & fix. If they suck then buy another GTP (solid one) & part that pig out. Might even be able to save a few bucks and snag a Regal

Hah, well it'd be a lot more expensive to give up on the car than it's gonna be to fix it. I got the code off the trans tag but I don't know how to read it, maybe someone can help with that. It's 611XAR W093.

There are pictures here of the car, PCM and spliced wiring mess. I'll put up some pictures of the individual unused connectors and the engine bay later, it looks like the guy used the old 97 GT harness and spliced all the 98 GTP PCM connecter wires and the 4t60e trans connector in, and left the mess.
GTP pictures by kwk6564 - Photobucket

I just had an engine fire and melted half my harness. The engine harness is not bad at all to change out, just be careful and watch for ground straps. Everything else is pretty much plug and play since all the pig tails go in their own places and used harnesses pretty much fall into place. With that said, I have found these harnesses to be car and year specific. I had to go here to find my harness and after three (the places I contacted gave me the VIN of the car the harnesses were pulled from and I called my local GM dealer to confirm which was correct for my car based on VIN) I found the perfect one. All the pins matched up and it was perfect. LINK ------> Car-Part.com--Used Auto Parts Market

Regarding your problem, I agree with Bill. Someone put the GTP motor in your GT car and that's it. I bet you are still running your GT harness and PCM. How does the car shift while driving? Does it shift weird or smooth? The GT vs GTP transmissions are different as well. Gearing difference calls for different shift points between the GT and GTP PCM's causing the transmission to shift weird. The reason I ask this is because would buying a used PCM help, or would it be better for him to figure out what he has first then go to Intense or Overkill and have a custom tune done for his specific application? He'll have to have his "new" PCM flashed anyway for his VIN and such if he has emission testing?? I dunno, just a random thought.

I would start out with a new harness. I bought mine for $100 ($75 for the harness and $25 shipping from OH to TN) Search that site and you'll find a good deal.

Makes sense. LOL Your original post was clear, I just got to rambling and thinking outloud about the PCM. Best thing to do is get the numbers off your PCM and call your local GM dealer and ask them to cross reference the numbers to see what it's for.

My only concern, to save you some money, because used PCM's are still $$$ and you might be stuck with another PCM that is still "wrong". Others can comment on my thoughts or tell me to hush if I am bringing more confusion to the situation.. Back to my concern, if you are going to spend $$$ on a PCM, would it benefit you more to purchase a tuned PCM for your application as opposed to getting another PCM IF another PCM has to be purchased?

IF the previous owner swapped the motor AND transmission out of a GTP then that's good. BUT if you are running a GTP motor with at GT transmission, that might cause issues because the gearing and shift points are different (to my knowledge). I am just trying to bring up questions that might be missed, others will hopefully comment about it..

I don't believe you can still be running the 97 PCM IIRC the 97 4t60e transmissions are run off vacuum. Hopefully Bill can tell you what the trans code means. Before you buy a harness you'll need to know what year the engine and trans are.

Take a pic of where the wiring harness goes to the trans and of the motor as a whole. Then take a pic of the inside of the throttle body and we'll be able to tell you what year your motor and trans came out of.

just pull the air intake off you don't need to pull the tb

That's a 99 or newer tb.

In your pictures on photobucket, are the plugs on pics 6 & 7 of 10 hooked up???? I know the plug in 7 of 10 is your ABS plug. The two in 6 of 7 (one round one rectangle) if they are close together, they to up on your driver side strut tower and are also for brakes. I'll post a couple pics of mine...