Power question. Turbo guys come in!
Originally Posted by RW99
phildo, where in the plumbing have you been making your pressure measurements? And do you have MAP readings too?
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From: boostville
Originally Posted by phildo
Should I go as far as backing the intake rockers off and pressurizing the intake manifold also?
If you have an MBC you will need to tighten it down a few turns so it doesn't bleed off pressure, just remember how many so you can put it back. With an EBC I'm not sure if the solenoid will bleed off w/no power.
Also make sure that its very quiet when you do the test because you are going to want to hear everything. You should only need to go up to 15psi (1bar) so watch your boost gauge. A properly sealed system should hold 15psi for a couple minutes with only a small amount bleeding off, if you can't to that then you have a leak someplace.
Originally Posted by alwaysinboost
no. don't remove anything except for the air filter and related piping on the compressor inlet (cold side). Just remove enough of the cold side plumbing to get the pressure tester on there. Leave all your VAC/boost lines, piping and ect in place just as if you were driving the car.
If you have an MBC you will need to tighten it down a few turns so it doesn't bleed off pressure, just remember how many so you can put it back. With an EBC I'm not sure if the solenoid will bleed off w/no power.
Also make sure that its very quiet when you do the test because you are going to want to hear everything. You should only need to go up to 15psi (1bar) so watch your boost gauge. A properly sealed system should hold 15psi for a couple minutes with only a small amount bleeding off, if you can't to that then you have a leak someplace.
If you have an MBC you will need to tighten it down a few turns so it doesn't bleed off pressure, just remember how many so you can put it back. With an EBC I'm not sure if the solenoid will bleed off w/no power.
Also make sure that its very quiet when you do the test because you are going to want to hear everything. You should only need to go up to 15psi (1bar) so watch your boost gauge. A properly sealed system should hold 15psi for a couple minutes with only a small amount bleeding off, if you can't to that then you have a leak someplace.
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From: boostville
Originally Posted by phildo
Maybe I am mis-understanding you but if I am thinking about it right if I pressurize the inlet side of the turbo and leave all the piping hooked up to the intake, then it will bleed off through the open valves on the motor. Also the EBC is hooked up to the waste gate on the exhaust so it will have no effect on this test.
as for the EBC, you should have 2 lines connected to the solenoid, one going to the wastegate and the other coming from a boost source. you should leave both attached. As I said earlier I don't know if an EBC will bleed boost like an MBC does but I don't think it will be an issue.
The fact that with your boost reference to the WG was pulled and you only made 15psi tells me there is an obvious problem with either the turbo not making boost or the WG not staying shut. with those two symptoms there are only a couple of things that you need to check in order to narrow it down and a boost leak should almost always be the first.
I have to say, for someone who said they are willing to try anything to fix this problem you sure have made every excuse and done all you can to avoid one of the easiest & cheapest test to perform in order to diagnose a problem with an FI car. taking apart your valvetrain to replace components is 100x the time, amount of work & cost it would have been to simply pressurize your intake plumbing. I personally would have never done something like that until all the other simple & cheap things had been checked first. Thats how you diagnose a problem, you start with the easiest thing and work up from there, not the other way around. A boost leak test is one of those things that should be performed on an FI car on a regular basis anytime you suspect a problem.
Originally Posted by alwaysinboost
if pressure does bleed off thru the exhaust it will be very minimal. In all the different cars I've pressure tested and with how many times I've done it not once was there an issue with air excaping thru the exhaust, not once. for whatever reason when you shut the motor off it likes to balance to a certain position, either an intake valve will be open and the exhaust will be closed or vise versa.
as for the EBC, you should have 2 lines connected to the solenoid, one going to the wastegate and the other coming from a boost source. you should leave both attached. As I said earlier I don't know if an EBC will bleed boost like an MBC does but I don't think it will be an issue.
The fact that with your boost reference to the WG was pulled and you only made 15psi tells me there is an obvious problem with either the turbo not making boost or the WG not staying shut. with those two symptoms there are only a couple of things that you need to check in order to narrow it down and a boost leak should almost always be the first.
I have to say, for someone who said they are willing to try anything to fix this problem you sure have made every excuse and done all you can to avoid one of the easiest & cheapest test to perform in order to diagnose a problem with an FI car. taking apart your valvetrain to replace components is 100x the time, amount of work & cost it would have been to simply pressurize your intake plumbing. I personally would have never done something like that until all the other simple & cheap things had been checked first. Thats how you diagnose a problem, you start with the easiest thing and work up from there, not the other way around. A boost leak test is one of those things that should be performed on an FI car on a regular basis anytime you suspect a problem.
as for the EBC, you should have 2 lines connected to the solenoid, one going to the wastegate and the other coming from a boost source. you should leave both attached. As I said earlier I don't know if an EBC will bleed boost like an MBC does but I don't think it will be an issue.
The fact that with your boost reference to the WG was pulled and you only made 15psi tells me there is an obvious problem with either the turbo not making boost or the WG not staying shut. with those two symptoms there are only a couple of things that you need to check in order to narrow it down and a boost leak should almost always be the first.
I have to say, for someone who said they are willing to try anything to fix this problem you sure have made every excuse and done all you can to avoid one of the easiest & cheapest test to perform in order to diagnose a problem with an FI car. taking apart your valvetrain to replace components is 100x the time, amount of work & cost it would have been to simply pressurize your intake plumbing. I personally would have never done something like that until all the other simple & cheap things had been checked first. Thats how you diagnose a problem, you start with the easiest thing and work up from there, not the other way around. A boost leak test is one of those things that should be performed on an FI car on a regular basis anytime you suspect a problem.
As far as the valvetrain goes, I had a issue there also. The pushrods were too long and those valve springs were extremely weak when we tested them. It just made sense with a power problem that the valvetrain had to be addressed to rule out the obvious.
Since my thinking hasn't been able to solve this I will try to just do what is suggested even if I think otherwise. That might be what is needed to solve this.
Thanks again
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From: boostville
Originally Posted by phildo
Since my thinking hasn't been able to solve this I will try to just do what is suggested even if I think otherwise. That might be what is needed to solve this.
So far I have a huge leak through the IAT sensor. Right through the center. Leaks as fast as you can put it in. I have 2 sensors here and they are both doing the same thing. Is there a alternate sensor I could use. Maybe something a little more boost friendly.
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is it leaking out of the grommet?
Try going to home depot and grab a brass tube fitting that can slip over the middle of the sensor (3/8" NPT i think?) and gorilla glue it to the sensor itself. Then tap the charge pipe for 3/8" and screw the sensor into it. The fitting looks like an adapter piece that is open on the top and male on the bottom. They cost under a $1. You'll likely need to file down the grooves on the sensor meant to seat it properly against the grommet.
Try going to home depot and grab a brass tube fitting that can slip over the middle of the sensor (3/8" NPT i think?) and gorilla glue it to the sensor itself. Then tap the charge pipe for 3/8" and screw the sensor into it. The fitting looks like an adapter piece that is open on the top and male on the bottom. They cost under a $1. You'll likely need to file down the grooves on the sensor meant to seat it properly against the grommet.
Originally Posted by JAvenger007
is it leaking out of the grommet?
Try going to home depot and grab a brass tube fitting that can slip over the middle of the sensor (3/8" NPT i think?) and gorilla glue it to the sensor itself. Then tap the charge pipe for 3/8" and screw the sensor into it. The fitting looks like an adapter piece that is open on the top and male on the bottom. They cost under a $1. You'll likely need to file down the grooves on the sensor meant to seat it properly against the grommet.
Try going to home depot and grab a brass tube fitting that can slip over the middle of the sensor (3/8" NPT i think?) and gorilla glue it to the sensor itself. Then tap the charge pipe for 3/8" and screw the sensor into it. The fitting looks like an adapter piece that is open on the top and male on the bottom. They cost under a $1. You'll likely need to file down the grooves on the sensor meant to seat it properly against the grommet.
Doesn't matter anyway cause it made 0 difference. Car is still a slug. Now I am looking for a way to measure the exhaust back pressure. I was going to adapt a compresion tester into the o2 hole but that is metric thread and there are no adapters available. So now the hunt begins.
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From: boostville
Originally Posted by phildo
It blew the rubber plug out of the back of the connector. This time I glued it in so it should be good now.
Originally Posted by alwaysinboost
It should be good? Does that mean you tested everything and you are able to hold 15psi w/o bleeding pressure off?
That is the least of my worries because there was absolutely no change in power. The problem is either backpressure or I have a issue with cam/heads.
This car makes no power. It started breaking up at 5000rpm's @6psi. I am trying to figure out a way to test backpressure through the o2 sensor hole. My pipes are all coated and I do not want to wreck it.
so ur gonna test it through 1 of the O2 sensors and only 1 O2?cause to test backpressure u actually have to get on the car.are u saying ur entire exhaust is coated and if so with what?
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From: boostville
Originally Posted by phildo
I can't get it to 15psi because my throttle body is leaking from the seal by the throttle blade at 10psi. It is leaking pretty bad. It is a brand new Holly 90mm. It bleeds off slowly at 8psi. Not nearly like what it was when I started.
your problem isn't going to go away on its own and its not going to fix itself either. if you don't want to help yourself then there is nothing myself or anyone else can do for you. I suggest you take your car to a shop that is more familiar with turbo cars then yourself and pay them to diagnose your problem before you wind up wasting even more of your time and money on this. I guarantee that you will be paying them to leak test your car.
Good luck with whatever you decide, I'm unsubcribing to this one.
Originally Posted by ddnspider
so ur gonna test it through 1 of the O2 sensors and only 1 O2?cause to test backpressure u actually have to get on the car.are u saying ur entire exhaust is coated and if so with what?
Originally Posted by alwaysinboost
your problem is right there. if you can't get your intake plumbing to hold pressure with an air compressor what makes you think the turbo can do it efficently?
your problem isn't going to go away on its own and its not going to fix itself either. if you don't want to help yourself then there is nothing myself or anyone else can do for you. I suggest you take your car to a shop that is more familiar with turbo cars then yourself and pay them to diagnose your problem before you wind up wasting even more of your time and money on this. I guarantee that you will be paying them to leak test your car.
Good luck with whatever you decide, I'm unsubcribing to this one.
your problem isn't going to go away on its own and its not going to fix itself either. if you don't want to help yourself then there is nothing myself or anyone else can do for you. I suggest you take your car to a shop that is more familiar with turbo cars then yourself and pay them to diagnose your problem before you wind up wasting even more of your time and money on this. I guarantee that you will be paying them to leak test your car.
Good luck with whatever you decide, I'm unsubcribing to this one.
At this point the car is so down on power a couple of psi would not matter. If you had listened to my explanation on this you would understand why I am thinking this way. I think the turbo system is working fine and there is another issue but the backpressure test will tell which direction to head.
Originally Posted by ddnspider
what kind of headers and crossover setup do u have?
Originally Posted by ddnspider
what kind of headers and crossover setup do u have?