Ahh...now that's a more thorough explanation! I wasn't told to do all that
but I'm going to try it.
Thanks,
James
-----Original Message-----
From: owner-dakota-truck@bent.twistedbits.net
[mailto:owner-dakota-truck@bent.twistedbits.net] On Behalf Of Bob Tom
Sent: Wednesday, July 12, 2006 3:31 PM
To: dakota-truck@dakota-truck.net
Subject: Re: DML: RE: Pressure Test
At 11:58 AM 7/12/06, Ray wrote:
>-----Original Message-----
>From: Jamie Calder
> My '96 318 won't go above 2000 rpm. I did a vacuum test and the cat
>seems fine.
>I'm curious how one determines the condition of a cat through a vacuum
test?
I haven't tried it myself but it involves diagnosing the effect of a blocked
exhaust on intake vacuum.
a) Connect a vacuum gauge to an intake manifold vacuum source.
b) Warm the engine to operating temperature, place the transmission in Park
and apply the parking brake.
c) Note and record the vacuum reading at idle.
d) Open the throttle until the engine speed is about 2000-3000 rpm.
e) Release the throttle quickly and record the vacuum reading.
f) Perform the test three more times, recording the reading after each test.
If the reading after the fourth test is more than one in-Hg lower than the
reading recorded at idle, the catalytic converter, muffler or exhaust pipes
may be plugged or restricted.
Once you've determined that there is a restriction, then the next step would
be to drill some holes in front & back of the cat & take readings from those
:-( If no or little difference in readings then it's the muffler. The main
reason why I've never tried it :-)
Bob
.
.
.------------------------------------------------------------------.
| Make your plans NOW to attend the National DML Meet in Colorado! |
| Date: July 15-23, 2006 - More info: http://meet.dakota-truck.net |
`------------------------------------------------------------------'
.
.
.------------------------------------------------------------------.
| Make your plans NOW to attend the National DML Meet in Colorado! |
| Date: July 15-23, 2006 - More info: http://meet.dakota-truck.net |
`------------------------------------------------------------------'
This archive was generated by hypermail 2b29 : Tue Aug 01 2006 - 10:33:41 EDT