Can holes in exhast cause low intake pressure?

[whheezzzz]

Hey guys, i was wondering if haveing rusted out holes in exuast pipe and muffler could cause you to have low vaccume pressure?

[cardboardpimp420]

holes in the exhaust usually doesn't affect the vacuum. I haven't done any exhaust work on my blazer but I do know that some cars have a vacuum line that goes to the cat. If that part is rusted out there is a possibility it can cause a problem because there would be a vacuum leak there. If that is the case you can plug up that vacuum line and that should solve that problem.

[old_master]

There are no vacuum lines connected to any catalytic converter. Some vehicles, mainly Ford, use a DPFE that measures exhaust back pressure used in calculating how much EGR to apply.

[MT-2500]

Not unless the exhuast or cat is plugged.
What is the engine vacuum reading at idle and at 2K rpm?
MT

[whheezzzz]

93 4.3 Vaccume at ilde is at 17 just below the green bar.at 2k im pretty sure i remember it going up to almost 20 or so,but i could be wrong,beacuse i thought that there was more vaccume at idle,maybe it went the other way lol depending on what you guys say is to if i will remeber or not lol. There are no fluctations at all,very steady. I havent seen any hoses leading to cat, but i do have a hole right after cat where it meets the muff and 2 long holes across the muff from the strapps. i dont hear any vaccume leaks any where,used propane,no fluctuations in idle,used stethescope,couldnt hear any hissing.

[ericn1300]

it doesn't matter how it affects engine performance, leaks in the exhaust system can be deadly and should be fixed immediatley.

[2percent]

I dont believe it will cause low intake pressure but It could affect the backpressure an exhaust system is suppose to give and that might affect your performance.

[whheezzzz]

thanks guys