Originally Posted by wjcollier07
Is there any way to measure the backpressure?
Okay, I have the factory manual right here in my lap...
1) Run engine until it'* in Closed Loop mode (i.e. fully warmed up)
2) Shut off engine
3) Remove the Oxygen sensor
4) With duct tape, block the vacuum inlet (rectangular port) on the intake manifold
5) Install the fuel pump pressure gauge in the nipple from Enrichment Tool J 26911
6) Install the gauge (I am NOT going to use the stupid factory-manual spelling "gage" here
) and nipple assembly into the O (I think they mean Oxygen sensor) port on the exhaust manifold
7) Start engine and run at 2500 rpm in "Park" and observe the backpressure
8 ) If backpressure measures 14 kPa (2 psi) or more, a restricted exhaust is indicated
9) Shut engine off
10) Inspect hte exhaust system for damaged or collapsed pipes
11) Inspect the muffler for heat distress or internal failure
12) If no other cause for excessive backpressure can be found, replace the convertor
13) Remove gauge and nipple assembly from intake manifold
14) Remove duct tape from vacuum inlet (rectangular port)
15) Intall Oxygen sensor in the exhaust manifold
If replacing the convertor is required, the manual says to cut the old one as close to the welds on either end of the convertor as possible -- i.e. they don't tell you to remove the intermediate pipe. (Cuts would be on the car side of the welds, so that the old welds go out with the old convertor.)
Personally, I would be guided by whatever plumbing comes with the replacement convertor; I certainly wouldn't hack anything off until I know what'* going on in its place.
Oh...and I noticed that I can hear a WHISTLING when its idling...could that be my vacuum leak?
It could; sure... and it might be an overpressure leak rather than a vacuum draw. Track it down with a stethoscope if you can and see what you've got.