Originally Posted by catmn39
Can a really bad muffler cause a loss of power?And can it cause a code reading for the EGR System?I get a code of 332 insufficient egr flow.Had the valve checked and it holds vacuum.Changed the actuator but still receive the code.

Yes, a plugged muffler can really affect operation. It can cause a huge loss of power because the engine can't breathe. As for the EGR, what vehicle are we talking about here? Make, model, year, engine please.

Yes, a plugged muffler can really affect operation. It can cause a huge loss of power because the engine can't breathe. As for the EGR, what vehicle are we talking about here? Make, model, year, engine please.
It's a 94 Explorer 4000

It's a 94 Explorer 4000
PURPOSE
The Exhaust Gas Recirculation (EGR) system is designed to reintroduce exhaust gas into the combustion cycle lowering combustion temperatures and reducing the formation of nitrous oxide.

OPERATION
The amount of exhaust gas reintroduced and the timing of the cycle varies by calibration and is controlled by factors such as engine speed, engine vacuum, exhaust system back pressure, coolant temperature and throttle angle. Most all EGR valves for your truck are vacuum actuated. The vacuum diagram is on the emission decal for each calibration.

Test the engine vacuum at idle and at about 2000 RPM. You should see about 15-17" of vacuum and if the throttle is snapped open, the vacuum will drop rapidly and recover rapidly. You should also test to see if engine vacuum is reaching the EGR valve and then to see if the EGR passages are even open.

PURPOSE
The Exhaust Gas Recirculation (EGR) system is designed to reintroduce exhaust gas into the combustion cycle lowering combustion temperatures and reducing the formation of nitrous oxide.

OPERATION
The amount of exhaust gas reintroduced and the timing of the cycle varies by calibration and is controlled by factors such as engine speed, engine vacuum, exhaust system back pressure, coolant temperature and throttle angle. Most all EGR valves for your truck are vacuum actuated. The vacuum diagram is on the emission decal for each calibration.

Test the engine vacuum at idle and at about 2000 RPM. You should see about 15-17" of vacuum and if the throttle is snapped open, the vacuum will drop rapidly and recover rapidly. You should also test to see if engine vacuum is reaching the EGR valve and then to see if the EGR passages are even open.
Thank you very much.I'll get a vacuum gauge and check it out.