Boost gauge on 200SX S13 CA18DET
peter
off the tapping on the ECCS manifold to the Evap canister. It gives a
reasonably steady reading except at tickover (need a smaller
restrictor). To check it's calibration I put a Vac gauge / fuel pump
tester on as well, both gauges give good agrement. It gives about
9psi at max boost but I was expecting about 6psi from postings and
tuning sites (norris designs).
The boost actuator looks standard - no adjuster is visible.
So has some one modded something?
Is the waste gate blocked?
In operation it seems to only make boost under acceleration as soon as
I try to cruise at about 80 it goes to just under 0psi (gauge - not
abs!) is this about right?
The vac gauge has engine condition markings on it and at tickover it's
running on 'late ignition or valve timing' - about 18cm Hg - is this
ok? The normal range is about 22cm Hg should I check the belt? I did
the ignition last week.
Basically I'm not too sure how the gauge should respond in use - lack
of research.
--
Peter Hill
Can of worms - what every fisherman wants.
Can of worms - what every PC owner has.
peter
>The vac gauge has engine condition markings on it and at tickover it's
>running on 'late ignition or valve timing' - about 18cm Hg - is this
>ok? The normal range is about 22cm Hg should I check the belt? I did
>the ignition last week.
>
Oops
Cm - should of course be inches.
That vac gauge is just a little bit old (about 25 years)!
chuck
vacuum to spark advance and or valve timing changed. I'd ignore the early /
late markings, and see if the engine vacuum is within the usual range for
the engine. If the engine has low vacuum, and a lot of miles, it most
likely also has low compression. (Assuming no vacuum leaks)
"peter" <peter...@skyshack.demon.co.uk> wrote in message
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Mika Tamminen
start to rise if the rpm“s are on normal boost speed...sounds someone has
turned up the boost or your wastegate vacuum lines aren“t sealing.
"peter" <peter...@skyshack.demon.co.uk> kirjoitti viestissä
news:fg7kus07bjf74cd5j...@4ax.com...
> I've got a boost gauge (modified oxygen cylinder gauge) and teed it
> off the tapping on the ECCS manifold to the Evap canister. It gives a
> reasonably steady reading except at tickover (need a smaller
> restrictor). To check it's calibration I put a Vac gauge / fuel pump
> tester on as well, both gauges give good agrement. It gives about
> 9psi at max boost but I was expecting about 6psi from postings and
> tuning sites (norris designs).
>
> The boost actuator looks standard - no adjuster is visible.
> So has some one modded something?
> Is the waste gate blocked?
>
> In operation it seems to only make boost under acceleration as soon as
> I try to cruise at about 80 it goes to just under 0psi (gauge - not
> abs!) is this about right?
>
> running on 'late ignition or valve timing' - about 18cm Hg - is this
> ok? The normal range is about 22cm Hg should I check the belt? I did
> the ignition last week.
>
> of research.
>
Jeremy Horsham
inlet manifold to the overboost sensor.
On the over run, i.e. decelerating from speed with the throttle close the
pressure is about -0.9 bar (obviously 0.1 absolute). At tick over I get
about -0.7 bar, cruising at 80mph its about 0 bar (same as you suggest). At
full throttle between 3,500 - 5000 rpm the pressure is about 0.7 bar,
dropping off to about 0.5 at the red line. I think this fall in pressue is
mainly due to restrictive intercooler and exhaust, which are all standard on
my car.
This is the 3rd S13 Ive had - all have shown the same sort of readings as
above.
Hope that helps
Jez
"peter" <peter...@skyshack.demon.co.uk> wrote in message
peter
>Ive installed boost gauges in my S13s - I teed off a pipe that goes from the
>inlet manifold to the overboost sensor.
I did not know there was one on the S13, I thought that it limited on
the hot wire air flow sensor reading. Where is it? Do you possibly
mean the solenoid that normally connects the manifold to the fuel
pressure regulator and to atmosphere when hot starting? On UK cars
it's located on the inner wing near the turbo and aft of the ignition
resistors but it does seem stupid to route the vac line from the
manifold on the offside to the nearside wing and back to the fuel
pressure regulator just below the manifold. It would have made more
sense to hang it off the manifold, there's already lots of stuff there
and one more would have made no difference.
>On the over run, i.e. decelerating from speed with the throttle close the
>pressure is about -0.9 bar (obviously 0.1 absolute). At tick over I get
>about -0.7 bar, cruising at 80mph its about 0 bar (same as you suggest). At
>full throttle between 3,500 - 5000 rpm the pressure is about 0.7 bar,
>dropping off to about 0.5 at the red line. I think this fall in pressue is
>mainly due to restrictive intercooler and exhaust, which are all standard on
>my car.
>
>This is the 3rd S13 Ive had - all have shown the same sort of readings as
>above.
Know of people who have had 2 but 3?
>
>Hope that helps
>Jez
>
0.7 bar = 10.15psi (my reading 9psi)
-0.7 bar = 20 inch Hg vac (my reading 18 inch Hg vac)
So it's possibly short at both ends. Not pulling enough vac at
tickover and not giving as much boost under acceleration.
<snip>
Jeremy Horsham
pressure regulator control solenoid valve on the inside wing.
My mistake, there isnt an overboost sensor - just looked in my manual. I
just assumed thats what it was...
"peter" <pet...@skyshack.demon.co.uk> wrote in message
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