Miatapower List Archive

This read-only message was archived from a public mail list.
Mail From: Xin Jin <(email redacted)>

Hello, I am having some trouble with very high idle. I figure that I turn to list for some help.

I am putting a 1.8 motor into a 1.6 with TEC-II. I got the motor to run. However, it starts up at about 1700 rpm, then it goes to about 2500 rpm for about 15 seconds. Then it dies. I think I either have an intake leak or a bad IAC.

I pressurized the intake manifold to see where the leak is. I could hear air coming out from back of the intake manifold(#3 and #4), but could not pinpoint the exact location. How air tight is the intake tract supposed to be? Am I going about this the right way? Where can I get some of that pink gas? How do I know if the IAC is bad?

thanks,

Xin

This read-only message was archived from a public mail list.
Mail From: "Robert Mangas" <(email redacted)>

FWIW a mechanic's stethoscope with the rod and diaphragm removed works well
for finding leaks. Hell, at that point you've just got a flexible plastic
tube stuffed in your ears so that'd probably work just as well ;)

Robert

>From: Xin Jin <(email redacted)>
>To: (email redacted)
>Subject: How to track down intake leak?
>Date: Mon, 27 Dec 2004 19:23:56 -0800 (PST)
>
>Hello, I am having some trouble with very high idle. I figure that I turn
>to list for some help.
>
>I am putting a 1.8 motor into a 1.6 with TEC-II. I got the motor to run.
>However, it starts up at about 1700 rpm, then it goes to about 2500 rpm for
>about 15 seconds. Then it dies. I think I either have an intake leak or a
>bad IAC.
>
>I pressurized the intake manifold to see where the leak is. I could hear
>air coming out from back of the intake manifold(#3 and #4), but could not
>pinpoint the exact location. How air tight is the intake tract supposed to
>be? Am I going about this the right way? Where can I get some of that
>pink gas? How do I know if the IAC is bad?
>
>thanks,
>
>Xin

This read-only message was archived from a public mail list.
Mail From: rmcelwee <(email redacted)>

Compressed air and soapy water has worked good for me a few times. I put th=
e water in a squeezable catsup bottle so I can aim the flow...

----- Original Message -----=20
From: Xin Jin=20
To: (email redacted)=20
Sent: Monday, December 27, 2004 10:23 PM
Subject: How to track down intake leak?


Hello, I am having some trouble with very high idle. I figure that I tur=
n to list for some help.

I am putting a 1.8 motor into a 1.6 with TEC-II. I got the motor to run.=
However, it starts up at about 1700 rpm, then it goes to about 2500 rpm f=
or about 15 seconds. Then it dies. I think I either have an intake leak o=
r a bad IAC.

I pressurized the intake manifold to see where the leak is. I could hear=
air coming out from back of the intake manifold(#3 and #4), but could not =
pinpoint the exact location. How air tight is the intake tract supposed to=
be? Am I going about this the right way? Where can I get some of that pi=
nk gas? How do I know if the IAC is bad?

thanks,

Xin

This read-only message was archived from a public mail list.
Mail From: "Larry Alster" <(email redacted)>

Check the back of the intake manifold. 1.6's have a rubber nipple there pl=
ugging a vacuum port used for the A/T. I'm not sure if 1.8's have the same=
port. Also a propane UNLIT can be passed near all your connections with t=
he engine running. Then you get a change in idle when you are near the lea=
k. The other thing is the compressed air in the tract and use the stethosc=
ope.


Larry

White Knight 1991 Crystal White #99 CSP
Silver Bullet 1992 Silverstone #17 EM FM I+ Turbo
Honey B 1992 Sunburst Yellow
Whooosh 2004 Titanium MazdaSpeed MX5

LowCountry Miata lowcountrymiataclub.net
Masters Miata
RAGS 074

----- Original Message -----=20
From: Xin Jin=20
To: (email redacted)=20
Sent: Monday, December 27, 2004 10:23 PM
Subject: How to track down intake leak?


Hello, I am having some trouble with very high idle. I figure that I tur=
n to list for some help.

I am putting a 1.8 motor into a 1.6 with TEC-II. I got the motor to run.=
However, it starts up at about 1700 rpm, then it goes to about 2500 rpm f=
or about 15 seconds. Then it dies. I think I either have an intake leak o=
r a bad IAC.

I pressurized the intake manifold to see where the leak is. I could hear=
air coming out from back of the intake manifold(#3 and #4), but could not =
pinpoint the exact location. How air tight is the intake tract supposed to=
be? Am I going about this the right way? Where can I get some of that pi=
nk gas? How do I know if the IAC is bad?

thanks,

Xin

This read-only message was archived from a public mail list.
Mail From: "Ross Kuhns" <(email redacted)>

Xin,

I've had some luck with carb cleaner spray. You can direct it with one of
the red rods in the tipand when the idle droops/dies you found where the
leak is; you can also see it get sucked in if it's a big enough leak.

I think some others have used better products(?) to spray in and around the
manifold.


Ross Kuhns


----Original Message Follows----
Compressed air and soapy water has worked good for me a few times. I put the
water in a squeezable catsup bottle so I can aim the flow...

----- Original Message -----
From: Xin Jin
To: (email redacted)
Sent: Monday, December 27, 2004 10:23 PM
Subject: How to track down intake leak?


Hello, I am having some trouble with very high idle. I figure that I
turn to list for some help.

I am putting a 1.8 motor into a 1.6 with TEC-II. I got the motor to run.
However, it starts up at about 1700 rpm, then it goes to about 2500 rpm
for about 15 seconds. Then it dies. I think I either have an intake leak
or a bad IAC.

I pressurized the intake manifold to see where the leak is. I could hear
air coming out from back of the intake manifold(#3 and #4), but could not
pinpoint the exact location. How air tight is the intake tract supposed to
be? Am I going about this the right way? Where can I get some of that pink
gas? How do I know if the IAC is bad?

thanks,

Xin