Installed Intake Manifold no got a question
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Joined: Sep 2002
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Installed Intake Manifold no got a question
ok two weeks ago i had a custom cold air intake,2.25 catback exhaust and a SR BBTB..
i then installed a highflow cat and my ported and polished intake manifold my question is:
before the intake manifold i would notice a pretty big increase in power at about 4,000..now it does seem to be there..could it just be that the smoothed it out more..or could it be i have a vacuum leak?
i then installed a highflow cat and my ported and polished intake manifold my question is:
before the intake manifold i would notice a pretty big increase in power at about 4,000..now it does seem to be there..could it just be that the smoothed it out more..or could it be i have a vacuum leak?
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Joined: May 2001
Posts: 11,851
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From: Rancho Palos Verdes, CA
Vehicle: 2008 Toyota Prius 2006 Suzuki SV650S
It could be a leak between the IM and the head, or between the TB and the IM.
The "easy" way to tell is to do the following. ONLY DO THIS ON A COLD ENGINE. When I say cold, I mean at least 8 hours of off time.
Grab WD-40 or "Starting" fluid for carbureted cars. Start the car, let the idle stablize for 15-20 seconds, the spray the WD-40 around the IM/Head joint, and around the TB/IM joint. If you hear sucking sounds, bubbling sounds, or if the idle surges or bogs, you know there's a leak.
You ONLY DO THIS ON A COLD ENGINE because you don't want the fluid dripping onto hot engine parts and possibly causing a fire.
If there is no change in noise, or idle, then you are leak free from the joints. Then check all of your vacuum hoses. (IM to Cruise, IM to Fuel Pressure Regulator, IM to Vacuum resivoior under the brake master cylinder. You do NOT want to spray those hoses with the fluids, they may eat your hoses. Use soapy water on them. If you hear sucking or bubbling...you've got a leak.
Once you've verified that everything is 100% leak free, Turn the car off, and pull the negative battery cable. Step on the brake light for 30 seconds to remove all trace voltage from the electrical system. Then reconnect the battery cable. That should Re-Set your ECU. Now drive your car agressively...and see if that performance comes back.
The "easy" way to tell is to do the following. ONLY DO THIS ON A COLD ENGINE. When I say cold, I mean at least 8 hours of off time.
Grab WD-40 or "Starting" fluid for carbureted cars. Start the car, let the idle stablize for 15-20 seconds, the spray the WD-40 around the IM/Head joint, and around the TB/IM joint. If you hear sucking sounds, bubbling sounds, or if the idle surges or bogs, you know there's a leak.
You ONLY DO THIS ON A COLD ENGINE because you don't want the fluid dripping onto hot engine parts and possibly causing a fire.
If there is no change in noise, or idle, then you are leak free from the joints. Then check all of your vacuum hoses. (IM to Cruise, IM to Fuel Pressure Regulator, IM to Vacuum resivoior under the brake master cylinder. You do NOT want to spray those hoses with the fluids, they may eat your hoses. Use soapy water on them. If you hear sucking or bubbling...you've got a leak.
Once you've verified that everything is 100% leak free, Turn the car off, and pull the negative battery cable. Step on the brake light for 30 seconds to remove all trace voltage from the electrical system. Then reconnect the battery cable. That should Re-Set your ECU. Now drive your car agressively...and see if that performance comes back.
i grabbed some wb-40 but i don't have time till wednesday to this this since i have exams and projects due.
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i think i found the problem!!!..i received my headers a few days ago ..so i took of my heat shield just to look at the stock headers..BIG *** crack in it..so it probably happened like the same day i put my BIM so that is why i noticed a power decrease!
Super Moderator
Joined: May 2001
Posts: 11,851
Likes: 2
From: Rancho Palos Verdes, CA
Vehicle: 2008 Toyota Prius 2006 Suzuki SV650S
I doubt it. The exhaust manifold didn't just "crack" overnight. That crack has probably been there for a LONG time. The stock exhaust manifolds are prone to cracking.
