02 monte ss 3.8

[bootism]

i have plenty of problems with this car now i need help first of all a month or so back i was driving the e-way and when i floored it to pass the engine rev up but that it if i eased into it would go. then a few weeks back the car wouldn't stay running i had to use both feet to keep it going. then i got e-way again and i couldn't get it above 50mph then when i got off the e-way the brakes felt like they were not power brakes hard to push. now when i start the car it shoot up to full throttle. here is what i've changed

throttle position sensor, fuel filter, wires, idle control sensor,fuel pressure reg. the codes that have come up are p0101 mass air range or performance problem
p0108 map sensor high input
p0131 o2 sensor low voltage
p0171 system to lean
when i have these codes erased the car barely idle then on the drive home it shoot up to full throttle

[maxwedge]

Check fuel pressure first then post back results, and stop replacing parts, the codes do not tell you to replace these parts but to diagnose the causes.

[bootism]

the fuel pressure is 53 pound with the key forward car not running

[maxwedge]

Originally Posted by bootism

the fuel pressure is 53 pound with the key forward car not running

Ok, now get the exhaust back pressure tested for a possible blocked cat, and repalce the fuel filter if not already done.

[richtazz]

I agree with Max on the blocked cat, or you have a BIG vacuum leak. If the car is a vin-k, check the elbow in the upper plenum where the brake booster hooks in for cracks or a split hose.

[bootism]

well i think i found one problem and on the upper manifold were the wire harness run from all the sensors tps, mas and so on it seems some how or another a hole about the size of a dime is now there. the problem what would cause this when i put my hand over the or i should say finger over the hole the idle comes right down to where it should be. i put a rag in the hole. i know doing this is not the smartest thing to do. anyway when i drove it it was acting just like what i described in the begining of the first post. i also know the rag did not completely plug the vacuum leak. same question again what caused the hole could a blocked cat cause this

[bootism]

Well I fixed the hole with j b weld and the idle go right down where it should be so that good. I took off in the car and it seems to have some power right of idle but if i try to floor it doesn't go just revs up. And sometimes it just studders right off of idle. I've pulled a code of low voltage to the MAS but I've check that and it 12 volts so that ok I'm thinking it the MAS itself or the cats clogged.