Thought everything was working good but....

[Florida240sx]

Sorry about my title, I can't spell tonight Fixed it for ya, WDI got my rps clutch in. And some other goodies. The other thing I installed was an autometer boost gauge bought from another nico member. At idle it read -15. When I boost it hits 4psi. Did about 5 runs(with my dad lol) It stays constant at 4psi. I'm suppose to have a .5bar spring so therfore 7.35psi.... Anythign other than a boost leak could be my problem? I don't know about the nylon tubing connecting to the boost gauge. I just figured it was correct...Any ideas on error of boost gauge? or do I just have a 3psi leak somewhere?(thinking egr valve)Any ideas at all on what could be up?It's goign to rain most of this week here so perhaps I"ll have a night off and do the DIY boost leak detector. But was wondering about the boost gauge whether or not I did it correctly.

[Craving4Boost]

15inhg at idle is way to low..it should be around 23inhg....i used to have the same problem as you....you need a VERY small hose to make that nylon tubing have a good connection....ive tried using those 1/8" hoses with zip ties and it just wasnt tight enough....so get a very small hose and stick that nylon tubing in..and then use a union fitting into a 1/8" so that it can T off FPR

[Craving4Boost]

actually my measurements in my head are all screwed up....do people usually use 1/4 or 1/8?? theres also a 3/16"....well just use a very small one lol...

[GEO]

-15inhg at idle ( cold start up ) is good... then when its warm it should be between 18-22inhg

[get_up_mark]

my boost gauge nylon hosewasnt long enough to reach my fpr line so i teed of the pfr line and put 1/8 hose on it and then stuck the nylon boost line inside there and zip tied it close. am i getting innacurate readings as well becuase of this? and also my vacuum is usally at like 15 or 16 when warmed up. what does this mean?

[Florida240sx]

Well I"m sure all myconnections is good except at the boost gauge.Hence I was holding the gauge by the nylon and it felland smashed the trim around it.... As soon as liek 3200rpms hit that things jumps. Started to think a .3bar spring would be 4.41psi... ALthough I don't even think Marc carried these.I don't know how exactly it should be at the gauge.It doesn't seem reliable to me.Thinking abotu just running vaccum line with a zip tie for the gauge.Instead of the nylon.Because i think it isn't flush with the unit.

[nissanfanatic]

Pressure test the system.

Where do you get your wastegate signal?

[Florida240sx]

hotpipe.Geo has his off hsi fpr and he has 10psi. With me running to the hot pipe(as instructiosn say) I should be 7psi. I assume it is because I beat an SR that had fmic.Although maybe something has happened since then.

[Craving4Boost]

i get 20inhg cold...23inhg warmed up

[AZhitman]

Keep in mind, my Tial had the WRONG spring in it. Could be your problem.

[GEO]

craving, thats not normal.. lol

[sunnys14]

Where do you get your wastegate signal?

hotpipe.QUOTE]

you get your wastegate signal off your hot pipe? weird... i get mine directly off the turbo compressor...

but anyways, maybe one of your boost gauge lines are kinked or loose. thats what happened to me and all my autometer gauge was trippin out!

[fiznat]

I always took my boost gauge readings from the intake manifold. That way, you see how much boost your engine is actually seeing. Often you get pressure drop over the IC and piping system- really you should be looking at actual boost, not just what the turbo is pushing.

Also if you want to see real engine vaccum, you're gonna have to look in the intake manifold as well. The throttle plate and suction from the intake stoke is what makes that vaccum inside your manifold-- outside of the manifold in the pipes I'm suprised you saw significant vaccum at all.

[Florida240sx]

So therfore if my gauge is sayign 4psi that is all I'm making?Tapped off the FPR line. I did do the calculations and if for some reaosn I had a .3bar spring that is 4.43 psi which today in 4th gear it was close to 5psi. My one IC line is kinked a little but it's not too bad.I could undersand maybe a small efficiency loss over it but not 40%. AZ you have too big of spring or too small like .3?

[Florida240sx]

Sorry about my title, I can't spell tonight Fixed it for ya, WD

Thanx man, I been having fights with the keyboard latley.

[nissanfanatic]

Use an air compressor w/gauge inline to see when the wastegate opens. I did that and found that my turbonetic springs were labeled wrong. 5psi would have been a lil faster than I expected.LoL

[Florida240sx]

Well going to re-route my signal line.And put a mbc in there with it.If I got time I'm going to open up the wastegate and see what spring is in there.

[mkory]

How do I open up the wastegate to check that the spring inside is the correct one I want? I bought the turbo used, and I want to make sure.

[Craving4Boost]

How do I open up the wastegate to check that the spring inside is the correct one I want? I bought the turbo used, and I want to make sure.

along the sides of the wastegate you'll see a good amount of those hexagon bolt things. i forgot whats it called. but you basically just take a hexagon Key thing or whatever its called and unscrew them all. the top should pop right off (and i literally mean pop off because of the spring so watch out when u take off the SECOND to last bolt because all the pressure will be on that last one so HOLD it down) and then you will see the spring. its nothing special, just a spring inside

BUT. that is really not the way to check if its the right spring, unless you have another spring to compare it with. the correct way to check what spring you have is to hook up an air compressor directly to the side port where you would usually have your vacuum source. keep adjusting your air compressor until you start to see your piston rising. but if you decide to hook it up WITHOUT taking it off the manifold...put your hand on the wastegate's dump and feel when the air comes out. its probably gonna be hot though lol...

anyone else got a better way?

[TheDecline]

ya im confused about what spring my wastegate has in it aswell. someone should probably ask marc and see exactly what he has been sending out.

as far as boost gauge, i wouldn't put a whole lot of faith in autometer. i have seen then read incorrect boost in a number of cars. unfortunatly thats all i have hangin around so if i ever get my car started thats what i will be using aswell. i suggest using the really tiny hard vinyl line for the gauge as its going to be the most accurate compared to a soft silicone hose.

try borrowing a friends gauge to see if it read the same.

[huguetpj]

Before you start messing around with stuff...

1. Your boost gauge has it's signal from the intake mani, right? So it's reading REAL boost "consumed" by the engine (for lack of a better word).

2. Where exactly is your wastegate side port signal coming from? a. Hot pipe means at the compressor b. After the compressor but before the intercooler c. After the intercooler but before the TB (which I don't think would qualify as hotpipe but wanted to put the option there)

If teh WG signal comes before the intercooler you could have some crappy boost loss through the pipes and/or intercooler, not necessarily a leak. Although 3PSI is quite a bit. I know that in my car I have a 4PSI boost loss through the pipes but @ 14PSI. What kinda of pipes are you using? Any tight bend in the system?

[fabio420]

I hate to stae the obviuos, or sound stupid, but maybe the boost gueage needs to be calibrated. My friend's gauge did that on his supra(it wouldn't show past 8 psi when we knew he was boosting as least 13 psi), then he calibrated and it worked fine.

[mkory]

Wait, I've got an internally gated turbo, the actuator is attached to the compressor housing. Is there any way to take this apart?

[Florida240sx]

Going to mess with it tomorrow when I get off work.Install an electric oil gauge. And then make my trip down to Vero.

[nissanfanatic]

Quote »BUT. that is really not the way to check if its the right spring, unless you have another spring to compare it with. the correct way to check what spring you have is to hook up an air compressor directly to the side port where you would usually have your vacuum source. keep adjusting your air compressor until you start to see your piston rising. but if you decide to hook it up WITHOUT taking it off the manifold...put your hand on the wastegate's dump and feel when the air comes out. its probably gonna be hot though lol...

anyone else got a better way?[/quote]Listen for it to open. Exhaust is pretty loud.

But removal is a sinch. Just remove it and check it the right way as I said to begin with.