Exhaust Restriction

PURPOSE
To determine if the exhaust system is sufficiently restricted to cause a performance problem.

RECOMMENDED PROCEDURE
A thorough visual inspection will find the problem quickly in most instances. If a measurement is necessary, install breakout box at Powertrain Control Module (PCM), measure voltage between Pin 30 and Pin 91 to allow the voltage signal to be monitored that will correlate to a specific pressure. Measure this pressure at high idle (maximum engine speed with engine out of gear, wheels blocked and brake engaged).

POSSIBLE CAUSES
Collapsed tail pipe, clogged tail pipe, closed exhaust back pressure device, clogged catalytic converter or damaged muffler.

TOOLS REQUIRED
Rotunda 104 Pin Breakout Box 014-00950 and Rotunda DVOM 105-00050