boost leak please help
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From: springfield Ma
boost leak please help
First off i searched before i posted this, i just got my car and really haven't beat on ,today was the first day i took it all the way threw to redline. i never drove an evo before mine so i thought it seemed fairly fast. Come to find out im only boosting like 7-8 psi. i mean it still pulls really hard but this just doesn't seem right to me. Car has auto meter nexxis gauges on it. Are the guages not just reading right or do you think i have a boost leak? If the car did come with a mbc where would it be installed, engine bay or cabin? The car has injen intercoller piping and a blow off valve if that helps.
Thanks guys any info would be greatly appreciated
Thanks guys any info would be greatly appreciated
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From: springfield Ma
what are all the mods done to this car you know of? brands? on the boost gauge what is vaccum reading?
a mbc should be noticible under the hood of the car. if you still are uncertain unbolt the intake filter box. you will see the stock boost contol solinoid and the nipples should be capped. youll also see vaccum lines which should run to a mbc. most likely the previouse owner had a mbc and when returning it to stock didnt put the stock lines on that have a brass pill in them and just reused the mbc vaccum lines
a mbc should be noticible under the hood of the car. if you still are uncertain unbolt the intake filter box. you will see the stock boost contol solinoid and the nipples should be capped. youll also see vaccum lines which should run to a mbc. most likely the previouse owner had a mbc and when returning it to stock didnt put the stock lines on that have a brass pill in them and just reused the mbc vaccum lines
here is a pic of what you are looking for under the intake box. notice the white hash lines on the stock tubing. if you tubing is all black youll need to get a mbc or go to mitsu and buy the stock lines
Check all the hoses and wiring on your boost gauge. Make sure it is properly connected to a boost/vacuum source on the manifold. Make sure there are no kinks in the nylon tubing running from the t-fitting to the gauge.
Now you need to get a boost leak tester. You have two options...
1) You can make you own tester <-- I made mine for literally under $5 following those directions.
2) Or you can buy one from the folks at BoostPro.net. The one from Boost Pro is nice because it has a pressure gauge right on the tester so you can do the boost leak test by yourself (normally you need a buddy to watch the boost gauge in your car so you know how much you've pressurized the intake system). In your case this pressure gauge feature might be especially nice because you aren't even sure the boost gauge in your car is reading properly. With this extra pressure gauge, you will be able to compare pressure readings between your boost gauge and the tester's pressure gauge and make sure they match. If the boost gauge in your car is reading lower than the one on the tester, you'll know your interior boost gauge is either broken or not hooked up properly.
Now you need to get a boost leak tester. You have two options...
1) You can make you own tester <-- I made mine for literally under $5 following those directions.
2) Or you can buy one from the folks at BoostPro.net. The one from Boost Pro is nice because it has a pressure gauge right on the tester so you can do the boost leak test by yourself (normally you need a buddy to watch the boost gauge in your car so you know how much you've pressurized the intake system). In your case this pressure gauge feature might be especially nice because you aren't even sure the boost gauge in your car is reading properly. With this extra pressure gauge, you will be able to compare pressure readings between your boost gauge and the tester's pressure gauge and make sure they match. If the boost gauge in your car is reading lower than the one on the tester, you'll know your interior boost gauge is either broken or not hooked up properly.
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Also note that if you have matched but low pressure readings on both gauges it means your boost gauge was working fine all along and you just have a boost leak.
Hope this all helps. Let me know if you have any more questions.
Hope this all helps. Let me know if you have any more questions.
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From: springfield Ma
Thanks guys, the car has injen intercooler upper and lower i think. It also has the injen intake, this might be part of the intercooler piping? The guages that are in the car are auto meter nexus. I have the boost guage, oil psi, and oil temp, Im a v8 guy, what do evo's run for oil pressure at idle im use too like 40-50 but my guage reads like 25-20. also the oil temp goes from 180-220.
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From: springfield Ma
This forum is awesome, you guys just saved me a bunch of money. I found the boost leak, the car is now boosting 18-19 psi. My leak was coming from a line going from a T connection near the intake to a rectangular plastic box near the fire wall. My only question is the line that was cracked at both ends has a hard plastic liner on the inside. The line that i put on fits tight but i think the diameter is bigger than the one that i took off. Also this line is transperant, something i had at the house. The car pulls like a freight train now but i thought stock boost was around 21. Could i be losing 2 psi threw this bigger line?
Thanks again everyone who posted!!
Thanks again everyone who posted!!
even w/ a bad leak, u should be running ATLEAST wastegate pressure which is around 12-14 (i forgot exactly this morning)....
now if ur leak is ridiculously bad, you will actually throw a CEL and your car will feel like crap. seeing your still pulling smoothly, i bet maybe you didnt fully tighten down the vacuum tube going to the gauge w/ zip tie etc... if u did, try replacing the gauge. autometers arent the best, agreed.
now if ur leak is ridiculously bad, you will actually throw a CEL and your car will feel like crap. seeing your still pulling smoothly, i bet maybe you didnt fully tighten down the vacuum tube going to the gauge w/ zip tie etc... if u did, try replacing the gauge. autometers arent the best, agreed.


