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Discussion Starter · #1 ·
I think the culprit is a solder joint. I cut into the number two cylinder power wire going to the coil. I now know this is a no no. I replaced the solder with a jell filled connector. I could ease the car up to the 6000 RPM figure however if I went to hard on the throttle the car would misfire anywhere from 4G and up. The plugs all look good and the car pulls great and runs strong as long as it wasn't floored.Does anyone have a better suggestion as to how I can repair the error I made when I cut into the coil wire. Wood Door Fixture Gas Cylinder
The car had codes poo16 and 17 and 302 and 303. I replaced the cam solenoids and did a oil and filter change. This has eliminated the skip however now if I let off the throttle quick under boost the motor goes in the limp mode. I loose almost all boost and power. any suggestions would be great.
 

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Discussion Starter · #3 ·
Isn't this the same problem you reported here: Missfires on cylinders 3 & 4 at high rpm, 2.0
Yes, I think I have the skip problem worked out, now the car looses boost and it does it if I am jacking the boost up and let off fast, The new code is P0299. If I go hard through the gears and let off easy, everything is fine and no more skipping. If any where in the run I let off fast, I loose boost down to 4 0r 6 PSI and it is slow coming. Same thing happens if I pass a vehicle and let off fast, it goes into that limp mode. When I first got the car if it went into the limp mode there was so much power loose that the car was a dog. Now when it goes into the reduced boost it still is very responsive compared to the stock engine.
 

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That sounds like it might be a BOV problem.
Have you double checked the vacuum line from the solenoid on top of the intake manifold to the BOV ?
 

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It sounds like you are having an issue with the blow off as @HHGadget stated. But we have to remember that you have an LE5 (essentially) so your boost is not controlled by the ECM. It is either being controlled by the wastegate spring or the boost controller.

I think you had stated that you are using the wastegate spring to control the boost. I am not sure how you have the wastegate plumbed. I would imagine the vacuum line is attached to the pressure side of the turbo. You should also have a BOV that is connected to the pressure side of the turbo and also to the intake manifold. When a BOV is functioning properly it is not going to allow the pressure in the charge system exceed the pressure in the intake manifold. This will happen when you let off the accelerator because the throttle plate closes. The turbo doesn't have brakes in it, it keeps on spinning and building pressure. This will cause a pressure difference between the charge system and the intake manifold and the BOV will open.

I am wondering if the BOV is getting stuck open and the reason why you are not able to build boost. The turbo would be spinning as if it is building boost and the ECM has been programed to expect a certain amount of air going into the engine and it's not getting there. That would be the reason why the ECM is going into limp mode.

I would look at your BOV and make sure it's not sticking. It could be getting stuck when the BOV has to open up all the way which would be when you have the accelerator pushed down pretty good and then you let off the accelerator.

Pull the BOV out and take it apart. Be careful as there are springs inside of it. Check the piston and make sure it is able to move it's full range without getting hung up at all.. Also read up on how to adjust it.

What is the make and model of your BOV?
 
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Discussion Starter · #7 ·
It sounds like you are having an issue with the blow off as @HHGadget stated. But we have to remember that you have an LE5 (essentially) so your boost is not controlled by the ECM. It is either being controlled by the wastegate spring or the boost controller.

I think you had stated that you are using the wastegate spring to control the boost. I am not sure how you have the wastegate plumbed. I would imagine the vacuum line is attached to the pressure side of the turbo. You should also have a BOV that is connected to the pressure side of the turbo and also to the intake manifold. When a BOV is functioning properly it is not going to allow the pressure in the charge system exceed the pressure in the intake manifold. This will happen when you let off the accelerator because the throttle plate closes. The turbo doesn't have brakes in it, it keeps on spinning and building pressure. This will cause a pressure difference between the charge system and the intake manifold and the BOV will open.

I am wondering if the BOV is getting stuck open and the reason why you are not able to build boost. The turbo would be spinning as if it is building boost and the ECM has been programed to expect a certain amount of air going into the engine and it's not getting there. That would be the reason why the ECM is going into limp mode.

I would look at your BOV and make sure it's not sticking. It could be getting stuck when the BOV has to open up all the way which would be when you have the accelerator pushed down pretty good and then you let off the accelerator.

Pull the BOV out and take it apart. Be careful as there are springs inside of it. Check the piston and make sure it is able to move it's full range without getting hung up at all.. Also read up on how to adjust it.

What is the make and model of your BOV?
the blow off valve is a HKS with a 1" hose that returns the air back into the cold air intake pipe after the sensor.
 

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OoOo you have a bypass valve.

do you know the model number of it? They usually have an adjustment to them and it controls how the valve "floats" if it's not set right once it opens it can end up staying open because of the pressure differential between the intake manifold and the charge pipe.

It makes more sense now. What the "BOV" (bypass valve) does is it takes the pressurized air from the charge side and dumps it into the intake. That air is still at pressure when it gets dumped back in to the intake where it then goes into the turbo and comes back out. It keeps on making this never ending loop and so long as there is a pressure difference between the charge pipe and the intake manifold it's going to hold that BOV open.

They can be really fickle to get right. This is why I went with a dual port so some of the air gets recirculated and some gets blown off to atmosphere this way I know the system will equalize properly.

I can't find a plumb back HKS BOV. I found 3rd party parts that make an HKS a plumb back but it is not designed to be one from the get go.
 

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Discussion Starter · #10 ·
OoOo you have a bypass valve.

do you know the model number of it? They usually have an adjustment to them and it controls how the valve "floats" if it's not set right once it opens it can end up staying open because of the pressure differential between the intake manifold and the charge pipe.

It makes more sense now. What the "BOV" (bypass valve) does is it takes the pressurized air from the charge side and dumps it into the intake. That air is still at pressure when it gets dumped back in to the intake where it then goes into the turbo and comes back out. It keeps on making this never ending loop and so long as there is a pressure difference between the charge pipe and the intake manifold it's going to hold that BOV open.

They can be really fickle to get right. This is why I went with a dual port so some of the air gets recirculated and some gets blown off to atmosphere this way I know the system will equalize properly.

I can't find a plumb back HKS BOV. I found 3rd party parts that make an HKS a plumb back but it is not designed to be one from the get go.
I will look up the model and let you know which one I have. Also right at the spot where the one inch line enters back into the intake pipe there is a vacuum line that hooks to a selnoide on the cold side of the turbo. I didn't put that on , the tuner did.
 

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Discussion Starter · #11 ·
OoOo you have a bypass valve.

do you know the model number of it? They usually have an adjustment to them and it controls how the valve "floats" if it's not set right once it opens it can end up staying open because of the pressure differential between the intake manifold and the charge pipe.

It makes more sense now. What the "BOV" (bypass valve) does is it takes the pressurized air from the charge side and dumps it into the intake. That air is still at pressure when it gets dumped back in to the intake where it then goes into the turbo and comes back out. It keeps on making this never ending loop and so long as there is a pressure difference between the charge pipe and the intake manifold it's going to hold that BOV open.

They can be really fickle to get right. This is why I went with a dual port so some of the air gets recirculated and some gets blown off to atmosphere this way I know the system will equalize properly.

I can't find a plumb back HKS BOV. I found 3rd party parts that make an HKS a plumb back but it is not designed to be one from the get go.
My HKS model SSQV and it is a recirculating valve. It comes with a one inch recirculating fitting.The intake has a solenoid on top and no vacuum lines are hooked to it. The turbo is a EFR and the BOV is the HKS. The vacuum line that goes to the front of the turbo and the BOV comes directly off the manifold and the solenoid at the turbo has lines going to the wastegate, cold side of the turbo and a line hooking into the 1" recirculating hose. This is the set up I'm running. Any suggestions you have to help me would be greatly appreciated.
ny
 

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I am totally at a loss with the 1 inch line comments.
The outlet to the charge pipes should be more than twice that no?
Like wise with the intake to the turbo.
Could you possibly post some photos?
 

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You are not sharing a vacuum line for the BOV are you? If you are you shouldn't be unless the connection on the intake manifold has a 3/8" inside diameter.
 

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This is how everything should be plumbed.

Rectangle Slope Line Font Parallel



You said you are using only the wastegate spring to control the boost. so there is no controller or solenoid. you do not have an ECM that is capable of controlling the BOV so there is no turbo bypass solenoid.

The ONLY thing that should be connected to your intake manifold is your BOV. This is so the BOV has air pressure on both sides of the piston. If the pressure in the intake manifold is lower then the pressure in the cold side charge pipe the piston opens which "blows off" air. In your case it takes that air and dumps it back into the intake pipe.

Since your boost control is done by the wastegate spring the wastegate only need to know what the boost pressure it. This is done from a vacuum line connected from the wastegate to the nipple sticking out of the front of the turbo. Nothing else is needed there.

The reason why I said to check your BOV is because if the piston gets stuck or the BOV is not tight enough you can end up with pressure from the turbo ending up in a constant circle. which would cause the issue you are describing.
 

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If you have any vacuum lines connected to a thing that looks like this.

Automotive tire Road surface Asphalt Bumper Gas



and it is on the front of the turbo check and see if there are any electrical wires plugged into it. If there isn't then I am not sure why that thing is even being used as it is doing NOTHING.

It should be connected like this anyhow

Asphalt Automotive tire Road surface Font Bumper


and if there is no electrical wires plugged into it then it is the same as attaching the wastegate directly to the front of the turbo.
 

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Now.... I am not sure why you have a BOV that is plumbed back anyhow. The EFR has one that is built into the turbo.

Wheel Automotive tire Locking hubs Disc brake Vehicle brake



see the integrated BOV?? If you are running both of these things then you are going to have some bumping heads going on.

If you want to run the HKS you will need to take that BOV off the front of the turbo and replace it with one of these.


I am thinking that you still have the EFR BOV and it's connected to something.


If you want to sue the one in the turbo then the HKS needs to be removed and the openings in the intake and the charge pipe closed off. A vacuum line from the intake manifold needs to run to the EFR BOV.
 

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Discussion Starter · #17 ·
Now.... I am not sure why you have a BOV that is plumbed back anyhow. The EFR has one that is built into the turbo.

View attachment 122985


see the integrated BOV?? If you are running both of these things then you are going to have some bumping heads going on.

If you want to run the HKS you will need to take that BOV off the front of the turbo and replace it with one of these.


I am thinking that you still have the EFR BOV and it's connected to something.


If you want to sue the one in the turbo then the HKS needs to be removed and the openings in the intake and the charge pipe closed off. A vacuum line from the intake manifold needs to run to the EFR BOV.
C4
Automotive fuel system Hood Automotive tire Motor vehicle Automotive air manifold

Automotive lighting Vehicle Automotive tire Light Hood

Now.... I am not sure why you have a BOV that is plumbed back anyhow. The EFR has one that is built into the turbo.

View attachment 122985


see the integrated BOV?? If you are running both of these things then you are going to have some bumping heads going on.

If you want to run the HKS you will need to take that BOV off the front of the turbo and replace it with one of these.


I am thinking that you still have the EFR BOV and it's connected to something.


If you want to sue the one in the turbo then the HKS needs to be removed and the openings in the intake and the charge pipe closed off. A vacuum line from the intake manifold needs to run to the EFR BOV.
I posted two photos, the intake manifold has a vacuum line going directly to the BOV, it also has a t in the line that goes to the front of the turbo. The solonide on the manifold isn't being used. The solonide at the turbo has a line going to the wastegate, one going to the nipple on the turbo and one that goes to the 1" recirculating line where it hooks into the intake pipe.
Automotive lighting Vehicle Automotive tire Light Hood

Now.... I am not sure why you have a BOV that is plumbed back anyhow. The EFR has one that is built into the turbo.

View attachment 122985


see the integrated BOV?? If you are running both of these things then you are going to have some bumping heads going on.

If you want to run the HKS you will need to take that BOV off the front of the turbo and replace it with one of these.


I am thinking that you still have the EFR BOV and it's connected to something.


If you want to sue the one in the turbo then the HKS needs to be removed and the openings in the intake and the charge pipe closed off. A vacuum line from the intake manifold needs to run to the EFR BOV.
This is a photo of the solonide on the front of the turbo.
 

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Discussion Starter · #18 ·
C4 View attachment 123007
View attachment 123006

I posted two photos, the intake manifold has a vacuu
Now.... I am not sure why you have a BOV that is plumbed back anyhow. The EFR has one that is built into the turbo.

View attachment 122985


see the integrated BOV?? If you are running both of these things then you are going to have some bumping heads going on.

If you want to run the HKS you will need to take that BOV off the front of the turbo and replace it with one of these.


I am thinking that you still have the EFR BOV and it's connected to something.


If you want to sue the one in the turbo then the HKS needs to be removed and the openings in the intake and the charge pipe closed off. A vacuum line from the intake manifold needs to run to the EFR BOV.

m line going directly to the BOV, it also has a t in the line that goes to the front of the turbo. The solonide on the manifold isn't being used. The solonide at the turbo has a line going to the wastegate, one going to the nipple on the turbo and one that goes to the 1" recirculating line where it hooks into the intake pipe. View attachment 123006

This is a photo of the solonide on the front of the turbo. One line hooks to the nipple on the turbo, the other to the wastegate and the last one goes to the recirculating hose.
[/QUOTE
My turbo has that plastic cover however it doesn't have the discharge pipe under it like the photo. The vacuum line that Ts off from the HKS vacuum line connects to that plastic diaphram cover on the turbo. I'm following what you are telling me however I wanted you to view how this is hooked up.
 

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Now I am really confused here.

What is the engine in this car?? What is the ECM in the car??
 
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