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Spyder 97 GST Spyder P0300 Code

ZubUchiha

Proven Member
75
0
Jul 30, 2021
Riverside, California
Hey y’all, I Just got a 97 gst spyder and it has a p0300 code. I changed the spark plugs and the check engine didn’t come on but halfway of driving it back home, check engine came back on and it started misfiring. When I start to accelerate it would feel as if the clutch was slipping, and the entire car would start to rumble and shake hard, but this would only happen sometimes. Another problem is that when I accelerate the rpms fluctuate up and down like it’s lagging as it’s going up, but when it’s in neutral, it goes up and down smoothly. The temperature gauge would also start to go up slowly past the halfway mark. Another question I have is when the car is idling in neutral and not moving, the rpm’s will drop below the normal range the car will vibrate as if it’s about to stall, any reason why this would be? My reader only shows this code and none other. Any help would be appreciated.
 

ZubUchiha

Proven Member
75
0
Jul 30, 2021
Riverside, California
Here is the video of the type of thing inside the tube that felt like burnt rubber

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Cherry

Proven Member
277
60
Jun 16, 2019
Hull, Georgia
Just posting to see updates on the thread. It is good though to get all of the basic maintenance done first. Just dont get overwhelmed with too much information and pace yourself. If you're just starting out its easy to get too much information in a small span of time.

Make checklists if you need to. They help a lot.
 

ZubUchiha

Proven Member
75
0
Jul 30, 2021
Riverside, California
Just posting to see updates on the thread. It is good though to get all of the basic maintenance done first. Just dont get overwhelmed with too much information and pace yourself. If you're just starting out its easy to get too much information in a small span of time.

Make checklists if you need to. They help a lot.
I believe I already beat you to it LOL. I’ve learned so much in such a short span, that I’ve honestly lost which way to go, but I will create checklists. The first is going to start with the vacuum leak that is coming from the tube directly underneath the air intake box. If anyone knows what that tube is called, or what the purpose is for that tube that circles around the right side of the bumper to the radiator is for. Let me know. I will post a diagram of where it is and what tube I need information on.

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That red outline is the outline of that tube that stretches across the right side of the car. The arrow is where the vacuum leak is coming from right underneath the air intake box. Does anyone know what part that’s called. I’m going to look for a replacement.
 

ZubUchiha

Proven Member
75
0
Jul 30, 2021
Riverside, California
Just posting to see updates on the thread. It is good though to get all of the basic maintenance done first. Just dont get overwhelmed with too much information and pace yourself. If you're just starting out its easy to get too much information in a small span of time.

Make checklists if you need to. They help a lot.
Thanks for keeping yourself updated with the thread, the more people that help, the more I feel appreciated. Since I am new to the dsm community, could you give me a list of basic maintenance that I should complete in order. I’m kind of lost, and would really appreciate a list of basic maintenance that I should complete with the car. My end goal is the P0300 code so that it can pass smog and get it registered. But a list would be helpful. Please let me know, thank you.
 

Dericsh

Supporting Member
1,090
402
Nov 25, 2002
Pearl River, Louisiana
Thanks for keeping yourself updated with the thread, the more people that help, the more I feel appreciated. Since I am new to the dsm community, could you give me a list of basic maintenance that I should complete in order. I’m kind of lost, and would really appreciate a list of basic maintenance that I should complete with the car. My end goal is the P0300 code so that it can pass smog and get it registered. But a list would be helpful. Please let me know, thank you.
I shared this with you in your intro thread but since it directly answers your post here I’ll reshare

 

motomattx

Proven Member
3,697
1,435
Dec 9, 2010
wampum, Pennsylvania
The electrical plug is a resistor used for the cars charging system, its listed as a relay, but its not really a relay inside of the box, its a resistor and a diode that does the job of what used to be a relay, it should have a plastic cover on it just like other relays, and no it should not be hanging there but many end up that way due to being pulled out of the plastic cover which should be bolted under the frame rail in the left front of the car.
 

pauleyman

DSM Wiseman
7,998
2,604
Nov 19, 2011
oklahoma city, Oklahoma
What are the spark plug wires connected to? I’d like to know what part that is.

For the boost leak test, the hissing coming from the air intake area, was actually a very big vacuum leak right underneath the air intake box. It was on the hose that runs around the right sight of the bumper. A friend suggested to use poxy to temporarily patch it up.

We tried spraying down the intake manifold and injectors area, but saw no bubbles or heard any hissing. I still believe there is some kind of leak coming from that area but I can’t pinpoint it because when I was using the hand pump, I was actually able to create pressure after spraying down the area.
They are connected to the coil pack.

I've read on down and your vacuum leak sounds like a boost leak as it is on the pressurized charge pipes for the intercooler. This is why we said perform a boost leak test. Any leaks mean air previously measured by the MAS never makes it to the motor. This affects air fuel ratios. I've seen holes in hoses and even the aluminum intercooler develop holes around the inlet and outlet due to corrosion. Any leaks need to be fixed.
The overheat issue also needs to be addressed. In my opinion that is your biggest problem. If it's serious the other problems may not matter.
 

ZubUchiha

Proven Member
75
0
Jul 30, 2021
Riverside, California
They are connected to the coil pack.

I've read on down and your vacuum leak sounds like a boost leak as it is on the pressurized charge pipes for the intercooler. This is why we said perform a boost leak test. Any leaks mean air previously measured by the MAS never makes it to the motor. This affects air fuel ratios. I've seen holes in hoses and even the aluminum intercooler develop holes around the inlet and outlet due to corrosion. Any leaks need to be fixed.
The overheat issue also needs to be addressed. In my opinion that is your biggest problem. If it's serious the other problems may not matter.
Yes I completely agree. But as you suggested, I can’t simply throw money at it hoping that each new part I put on it would solve the issue. What would you suggest on how to figure out what causes the overheating.

Just for some details and insight to make it more clear, I’ll explain the circumstances of when and how it overheats. When driving around on city roads, it does not overheat, it simply stays at the midline. When going up a hill or on ramp onto a freeway, the temperature starts to go up and reaches about 3/4 of the gauge. And when driving on the freeway, simply accelerating increases the temperature, but letting go of the gas makes the temperature drop to, at most, the midline, nothing below. I don’t think it’s a closed thermostat otherwise the temperature would increase as soon as I turn it on, but I don’t have much knowledge on the thermostat either. Driving it around the city would also cause it to increase, but it stays in the midline, even when I rev it high, it will slightly go up. I have no way to tell it it’s a bad water pump. The vacuum leak very well could be causing the overheating since the air doesn’t go into the intercooler and instead leaks out right before entering the intercooler. The last time I used a scanner, my LTFT was 11.7 so it’s definitely changing the air/fuel ratio since it needs more fuel, but it doesn’t have a sufficient amount of air since it’s exiting the system through a leak. This is my understanding, but correct me if I’m wrong. If you have suggestions on how or what to test in order to figure out what could be causing the overheating, I would greatly appreciate it.
 

ZubUchiha

Proven Member
75
0
Jul 30, 2021
Riverside, California
The electrical plug is a resistor used for the cars charging system, its listed as a relay, but its not really a relay inside of the box, its a resistor and a diode that does the job of what used to be a relay, it should have a plastic cover on it just like other relays, and no it should not be hanging there but many end up that way due to being pulled out of the plastic cover which should be bolted under the frame rail in the left front of the car.
So what exactly happens when it is disconnected? I was able to find out where it was plugged into so I plugged it back in, but it look like there was something else securing it as well which it didn’t seem to have, so let me know how it works exactly, and if there are any suggestions to hold it better in place. Thank you very much!
 

motomattx

Proven Member
3,697
1,435
Dec 9, 2010
wampum, Pennsylvania
So what exactly happens when it is disconnected? I was able to find out where it was plugged into so I plugged it back in, but it look like there was something else securing it as well which it didn’t seem to have, so let me know how it works exactly, and if there are any suggestions to hold it better in place. Thank you very much!
The car from the factory was designed to use the alternator light in the cluster to turn the alternator on to charge the car, that resistor is there in case your alternator bulb would burn out, it would still allow the alternator to turn on and charge rather than leave you on the side of the road. If you disconnect it nothing would happen if your alternator/charge bulb in your dash is still good, if that bulb is bad your car would not be able to charge, one of the two have to be able to pass electric through to the voltage regulator in the alternator for your car to charge, so its a backup, I recommend leaving it alone if you still have the stock alternator, secure it how ever you can, but do get a lid on it.
 

Cherry

Proven Member
277
60
Jun 16, 2019
Hull, Georgia
Thanks for keeping yourself updated with the thread, the more people that help, the more I feel appreciated. Since I am new to the dsm community, could you give me a list of basic maintenance that I should complete in order. I’m kind of lost, and would really appreciate a list of basic maintenance that I should complete with the car. My end goal is the P0300 code so that it can pass smog and get it registered. But a list would be helpful. Please let me know, thank you.
The basic stuff is some stuff you already did. Spark plugs and wires, coolant, oil, fuel filter. Those are the absolute first things I would do and making sure the things like the radiator fans work. Check hoses for cracks or hardness.

Just to limit some information, what Pauley wants to do is just make sure everything of the coolant system is in functioning order. Its like if you have a hot CPU in a computer its much more of a priority than a memory stick not working for example. Depending on the cooling system you have there are things you want to check, dust clogging air cooler fins, dust on fans, case fans / CPU fans not working, if its a water cooling system if the radiator fans are working, air in the system, radiator mounted higher than the CPU block so if there is air in the system it gets trapped there instead of in the block, proper application of thermal paste. I seen you had some experience with computers is why I brought the computer stuff up.

So basic maintenance / overheating issue are top priority.
 

pauleyman

DSM Wiseman
7,998
2,604
Nov 19, 2011
oklahoma city, Oklahoma
Yes I completely agree. But as you suggested, I can’t simply throw money at it hoping that each new part I put on it would solve the issue. What would you suggest on how to figure out what causes the overheating.

Just for some details and insight to make it more clear, I’ll explain the circumstances of when and how it overheats. When driving around on city roads, it does not overheat, it simply stays at the midline. When going up a hill or on ramp onto a freeway, the temperature starts to go up and reaches about 3/4 of the gauge. And when driving on the freeway, simply accelerating increases the temperature, but letting go of the gas makes the temperature drop to, at most, the midline, nothing below. I don’t think it’s a closed thermostat otherwise the temperature would increase as soon as I turn it on, but I don’t have much knowledge on the thermostat either. Driving it around the city would also cause it to increase, but it stays in the midline, even when I rev it high, it will slightly go up. I have no way to tell it it’s a bad water pump. The vacuum leak very well could be causing the overheating since the air doesn’t go into the intercooler and instead leaks out right before entering the intercooler. The last time I used a scanner, my LTFT was 11.7 so it’s definitely changing the air/fuel ratio since it needs more fuel, but it doesn’t have a sufficient amount of air since it’s exiting the system through a leak. This is my understanding, but correct me if I’m wrong. If you have suggestions on how or what to test in order to figure out what could be causing the overheating, I would greatly appreciate it.
Replacing a thermostat just as a matter of maintenance is cheap enough. Did you verify fans are working? Did you verify coolant again? Short of that, I would say you need a compression and leak down test to rule out anything more serious inside the motor. Water pumps generally do not "not cool" something. They sorta work or they don't. Meaning if they fail they will leak. An impeller spinning incorrectly but the pump still "works" is unlikley.
 

ZubUchiha

Proven Member
75
0
Jul 30, 2021
Riverside, California
Replacing a thermostat just as a matter of maintenance is cheap enough. Did you verify fans are working? Did you verify coolant again? Short of that, I would say you need a compression and leak down test to rule out anything more serious inside the motor. Water pumps generally do not "not cool" something. They sorta work or they don't. Meaning if they fail they will leak. An impeller spinning incorrectly but the pump still "works" is unlikley.
I can verify it has enough coolant, more than the full line. I did not remove any coolant since it has an overflow tube, so any excess amount will just leave the system. I will check again to verify if fans are working. Which fan is for the engine. I do not want to confuse it with the AC fan?
 

pauleyman

DSM Wiseman
7,998
2,604
Nov 19, 2011
oklahoma city, Oklahoma
I can verify it has enough coolant, more than the full line. I did not remove any coolant since it has an overflow tube, so any excess amount will just leave the system. I will check again to verify if fans are working. Which fan is for the engine. I do not want to confuse it with the AC fan?
You do not check fluid level only in the reservoir. You need to look under the cap.
Engine fan is passenger side I believe.
 

Cherry

Proven Member
277
60
Jun 16, 2019
Hull, Georgia
I can verify it has enough coolant, more than the full line. I did not remove any coolant since it has an overflow tube, so any excess amount will just leave the system. I will check again to verify if fans are working. Which fan is for the engine. I do not want to confuse it with the AC fan?

Having the fluid between the lines in the reservoir is important for the coolant light to not come on. Check it under the radiator cap. Just take the cap off, take a pic and post it here just to be safe.

Fan on passenger side is the engine fan, AC fan is on the driver side. At least its that way on the 1g's and I dont see why they would change it on a 2g.
 

ZubUchiha

Proven Member
75
0
Jul 30, 2021
Riverside, California
Update:

I checked the coolant in the radiator cap, it was fine and still bright green. I patched up the leak with epoxy and when I left my friends house it was driving fine, no misifiring, no overheating, the rpms would go up smoothly. But halfway through, the rpms initially started jumping again very slowly as if there was either another leak, or the leak I patched up was opening again. And then it started misfiring and check engine turned on.
 

Cherry

Proven Member
277
60
Jun 16, 2019
Hull, Georgia
There are many points for a vacuum leak. Those points range from right behind the MAF sensor all the way to the intake manifold and injectors. Using Epoxy to fix leaks could work on solid surfaces or anything that isnt flexible or there is something you need to get access to.

The leaks are usually on any connecting point or o-rings / seals. There are some o-ring insulators around the injectors that go into the head, there are seals in the throttle body, and many connection points from the MAF to the throttle body along with the throttle body to the intake manifold and intake manifold to the head.

I dont have a turbo on mine (yet, have more important things to tackle) but I would at least check a few things I had troubles with, the Injector o-ring lower insulators being one of them, these can get hard and not seal around the injector anymore. If they are hard, replace them. Check the vacuum hoses for cracking. If you see anything like cracking or it feels hard and not soft, I would go ahead and replace those as well. Its one of the basic maintenance things you should do anyways. Especially when you get a used car as old as ours are getting. Those heat cool cycles can do a number over the years.

Boost leak tests will be the way to go when trying to find a vacuum leak though.
 

ZubUchiha

Proven Member
75
0
Jul 30, 2021
Riverside, California
There are many points for a vacuum leak. Those points range from right behind the MAF sensor all the way to the intake manifold and injectors. Using Epoxy to fix leaks could work on solid surfaces or anything that isnt flexible or there is something you need to get access to.

The leaks are usually on any connecting point or o-rings / seals. There are some o-ring insulators around the injectors that go into the head, there are seals in the throttle body, and many connection points from the MAF to the throttle body along with the throttle body to the intake manifold and intake manifold to the head.

I dont have a turbo on mine (yet, have more important things to tackle) but I would at least check a few things I had troubles with, the Injector o-ring lower insulators being one of them, these can get hard and not seal around the injector anymore. If they are hard, replace them. Check the vacuum hoses for cracking. If you see anything like cracking or it feels hard and not soft, I would go ahead and replace those as well. Its one of the basic maintenance things you should do anyways. Especially when you get a used car as old as ours are getting. Those heat cool cycles can do a number over the years.

Boost leak tests will be the way to go when trying to find a vacuum leak though.
The issue for me is that I don’t know what a lot of these tubes or parts are called. I’ve already done a boost leak test and could hear hissing from the leak I patched up. However, I don’t know what the hose piece is called so I don’t know what piece to look for. Another thing is injectors, I don’t know how to take them off, or inspect which pieces since I’ve never done it before, and I’m more so worried I’ll make things worse. The epoxy I applied onto the hose last nice was connected to a hose looked old, he’d and cracked. I’m willing to learn everything, but I don’t know where to start looking. I only have a couple days before I go back to school which is about 2 hours away so I need to figure out the best plan to tackle this misfiring/overheating issue.
 

ZubUchiha

Proven Member
75
0
Jul 30, 2021
Riverside, California
Did you take any photos of what you glued so we can see what the part is and help you find a proper replacement?
I forgot to take photos when I was sealing it but it’s right underneath the air intake box. You can kind of see the tape underneath the air intake box.

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ZubUchiha

Proven Member
75
0
Jul 30, 2021
Riverside, California
Here’s a quick update:

I took my car to a mechanic and he’s still trying to diagnose what’s causing the misfires as well as overheating, however, he told me there was a water pump leak. He also showed it to me and the leak was accumulating on the pump itself and looked green/wet. He’s charging $300 for the labor minus the part. Is this a good deal?
 

Dericsh

Supporting Member
1,090
402
Nov 25, 2002
Pearl River, Louisiana
If the water pump needs replacing you might as well be doing a whole timing belt job. Sure, $300 isn’t bad until that doesn’t fix it and then you get another 3-500 quote for whatever he wants to guess next.
 
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