building no boost after boost leak test

[jcarmichael]

I fixed boost leaks at my TB, and bov then checked all my ic piping.. I couldn't get any pressure to build at all from the turbo up. from the TB up it was holding decently well. any how last week I changed my exhaust housing think my waste gate was sticking changed out with another exhaust housing I had and instead of it trying to boost right away and wanting to die when coming to a stop. now its building like 2 lbs of boost and doesnt feel nearly as bad to drive and when I come to a stop it idles down a bit but not as bad. not sure it makes a big difference but I have a 2g manifold with one nut on one of the studs, on a 16g exhaust housing on a 14b inlet side and the stock o2 housing.

thanks for the help
sorry for the grammar at a loss right now and its 5 am here gotta be up in like 3 hrs when my daughter wakes up.

Josh

 

[4G63_GSX]

have you checked to make sure your wg is good? it could be stuck open, also have you checked all your vaccum lines? the idle problem sounds like a vaccum line.

 

[9!'clipseDOHC]

So, I'm confused. To confirm, your set up is a 2g manifold (apparently only bolted down with 1 nut ???), a 14b with a 7 cm hotside, and a 1g o2 housing. And you issue is that you have boost leaks, your car isn't building much boost, and it idles low at a stop. Right?

First, please tell me that I read that bit about one nut holding you manifold on wrong. But if I did, fit that first. How can you expect your turbo to build boost if the exhaust is leaking out before it even get to to the turbo? Also make sure you have all of the turbo/exhaust gaskets installed. The turbo gaskets needed are:

• Head to manifold (exhaust manifold gasket)
• Manifold to turbo (turbine inlet gasket)
• Turbo to o2 sensor housing (turbine outlet gasket)
• o2 housing to downpipe (downpipe gasket)

Then, continue doing boost leak tests and fix the ALL leaks you find (no mater how small you think they may be). This will solve a LOT of issues, give you more power, and better gas mileage.

Finally after fixing all your boost leaks, properly set your BISS screw to get your idle dialed in. 1G BISS Adjustment.

 

[dino4g63]

I agree with 9!'clipseDOHC; if you only have one nut holding your exhaust manifold on, it is leaking. It is probably leaking bad. I large leak all the way around your manifold adds up to a surface area as large, if not larger than a wastegate port. You need to get that fixed before you can diagnose your boost issue.

 

[jcarmichael]

sorry guys I must have worded it wrong meant that I have all but one nut on the manifold. like I have 8 out of 9. the only one not in is the bottom right corner because it is a pain to get to but the stud is still there . how can I tell if the waste gate is bad, the one I had on it at first when I took off was rough to open and close this one on there now is quite a bit easier. that is with it off the car though doesn't move with it on I don't believe. I took my bizz screw out so I could do its o ring, but I don't have the tool to set it back to the correct place in all that tried to read the vfaq on it.

also I have all the gaskets on there as well the manifold gasket is brand new from when I did my arp head studs and head gasket last month. The rest are not but they were metal and didn't look bad.

 

[9!'clipseDOHC]

sorry guys I must have worded it wrong meant that I have all but one nut on the manifold. like I have 8 out of 9. the only one not in is the bottom right corner because it is a pain to get to but the stud is still there . how can I tell if the waste gate is bad, the one I had on it at first when I took off was rough to open and close this one on there now is quite a bit easier. that is with it off the car though doesn't move with it on I don't believe. I took my bizz screw out so I could do its o ring, but I don't have the tool to set it back to the correct place in all that tried to read the vfaq on it.

also I have all the gaskets on there as well the manifold gasket is brand new from when I did my arp head studs and head gasket last month. The rest are not but they were metal and didn't look bad.

Well, that is good to hear about the manifold! If you pop the wastegate actuator's arm off the wastegate, it should move freely.

The only tool you need to install the BISS screw is a philips head screwdriver. And then 2 jumper wires with alligator clips (which you can get at any auto parts store for a few bucks) to ground the pins to properly set it.

 

[jcarmichael]

also problem is with my ecm link, I have my idle set to 900 rpms. after reading the bizz screw thing since I take the ecu out of the equation when I do the test I will get it to idle at 750, but when I hook everything back up my idle should be back at 900 because the ecu is back in control then. but we will see i've tried just about everything else I can think of the last week. it runs way better then last monday but still a bit sketchy.

 

[dino4g63]

I would check the wastegate vacuum line connections and maybe swap back to your old wastegate. It wouldn't hurt.

 

[jcarmichael]

ok yea the wastegate moved good last night without the rod on it. checked before putting it on the car didn't want to go through that again . for some reason I read a vfaq last week that said you had to have a special tool to adjust it could of been for the isc motor. I am not sure but on the vfaq it said to borrow it from a machanics shop and what not.

another quick question I will do the bizz setting today. I ordered the caps for my ecu power supply been meaning to change them but then got stuck on this problem. I am almost certain they wouldn't be causing this issue but would it be worth changing them today or focusing on something else.

 

[9!'clipseDOHC]

also problem is with my ecm link, I have my idle set to 900 rpms. after reading the bizz screw thing since I take the ecu out of the equation when I do the test I will get it to idle at 750, but when I hook everything back up my idle should be back at 900 because the ecu is back in control then. but we will see i've tried just about everything else I can think of the last week. it runs way better then last monday but still a bit sketchy.

Its "BISS" not Bizz. I thought it was just a typo earlier but you keep calling it bizz. This is the VFAQ on how to set it: http://www.vfaq.com/mods/BISS-1G.html but since you have ecmlink you can just turn it until the ISCPosition is ~30.
Screwing the BISS in reduces the amount of air that reaches the intake manifold, screwing the BISS out increases the flow. If the only problem is that the BISS needs to be adjusted, simply adjust the BISS until the ISCPosition value logged in DSMLink/ECMLink hovers around 30 at normal warm-engine idle in neutral. This produces better results than following the service-manual procedure.

idlesurge [ECMTuning - wiki]
In order for the ECU to attempt to control idle speed at all requires that the ECU know that the throttle is closed. The ECU knows this by the state of the idle switch, so make sure that the idle switch is working by logging IdleSw in DSMLink/ECMLink or use DSMLink/ECMLink to simulate the operation of the idle switch. Idle surge results from the ECU being forced to limit idle speed by shutting off the injectors until the engine speed drops low enough. When the ECU re-enables the injectors, the engine speed jumps back up.

Ignition timing also has some effect on idle speed. In fact, the ECU normally varies ignition timing at idle to provide fine control over the idle speed. Make sure that base ignition timing is set properly.

If you are running a configured idle speed that's higher than stock, it's possible to observe a slight oscillation in idle speed even when everything else is working properly. This is because, by default, the timing tables in the ECU significantly advance ignition timing as the engine speed rises above 750 rpm, and engine speed tends to increase as ignition timing is advanced. You'll want to reduce this positive feedback by retarding the ignition timing at idle and slightly above idle. It also helps by giving the ECU's fine idle control mechanism more authority.

Also, as your idle speed setting is increased, the intended idle speed begins to get pretty close to the rpm at which the ECU cuts fuel when the idle switch is active. A good rule of thumb is to set the Coasting FC Offset to your rpm setting minus 900. For example, if your intended idle speed is 1100 rpm, set the Coasting FC Offset to 200 to raise the fuel-cut threshold by 200 rpm. Doing so also helps ensure that the idle switch will deactivate before the engine speed increases to the coasting fuel-cut threshold during no-load throttle application.

 

[jcarmichael]

awesome I will go do that here in about 30 minutes. need to make sure I am logging the ISC value in my table don't believe I am but does seem to be a lot easier from the description. with the idle switch setting that has to do with TPS adjust correct?

also sorry about the bizz and biss mistake for some reason I thought I was spelling it wrong bad thing is they both come up as a spell check error,

I also haven't had a chance to set my base timing, due to not having a timing light. I know its suppose to be 5 degrees when I took my head off last month I just left cam angle sensor on the head to avoid moving it in hopes it was already set and good to go. however I've known I needed to adjust it just broke every week and have to get something else always.

 

[9!'clipseDOHC]

awesome I will go do that here in about 30 minutes. need to make sure I am logging the ISC value in my table don't believe I am but does seem to be a lot easier from the description. with the idle switch setting that has to do with TPS adjust correct?

also sorry about the bizz and biss mistake for some reason I thought I was spelling it wrong bad thing is they both come up as a spell check error,

I also haven't had a chance to set my base timing, due to not having a timing light. I know its suppose to be 5 degrees when I took my head off last month I just left cam angle sensor on the head to avoid moving it in hopes it was already set and good to go. however I've known I needed to adjust it just broke every week and have to get something else always.

The idle switch lets the ECU know if the throttle plate is open or closed. If it isn't working properly you can simulate it and then it goes off of the TPS. The thing to log to set the BISS screw is ISCPosition.

I would try to double check the base timing. If you ask around i'm sure you could find someone who has one that you could borrow. Or you can buy a cheap on for around $30-$40.

 

[jcarmichael]

yea I thought about asking a friend. when ever I adjust the isc position here in a second its raining out trying to get motivated to go out there. I will log it and post after words.

here are a couple after I made the adjustment, maybe you guys can get an idea from the logs of what is going on. sorry I didn't shorten them down, it still idles down when I come to a stop unless I slowly come to a stop downshifting wise. also says I am getting boost but doesn't feel like I am actually. only thing I can really think at this point is I sitll have a boost leak big somewhere. I am really at a loss cars running better then last week on a positive note. the isc position wasn't all the way accurate at first adjusted it to 30 but with having a 180 thermostat it was moving a bit here and there depending on my coolant temps. not a big deal I don't think.

thanks again for the help
Josh