Pooparu Posted May 23, 2008 Share Posted May 23, 2008 So what I basically did was I put little filters on all four spots where the hoses connected to the bottom of the stock intake tube, then just got a 6” straight pipe and some fittings to relocate the intake to where the spare tire was. Well I put it all together and what’s happening is I’ll start it up and it’ll run fine for about 5-10 seconds then die. Any ideas on why, and how can I make this work? Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted May 23, 2008 Share Posted May 23, 2008 You can't - on fuel injected engines the crankcase is part of the manifold vacuum system - that's how the PCV works, and the air circulateing through the whole system is metered by the MAF. It's a closed system and each of the little filters you added is a vacuum leak. A carburetor is what's known as a "demand feed" system. It's entirely dependant on manifold vacuum to "pull" in air and fuel. Fuel injection is not demand driven - the ECU introduces fuel based entirely on the air passing by the MAF sensor. Thus a closed system is needed or you are pulling air (past the rings, ect) from places other than through the MAF sensor. All those filters are supplying "unmetered" air to the engine and the ECU is cutting the fuel down based on an incorrect MAF signal - result being the engine dies from lack of fuel. The initial cold-start enrichment is the only thing keeping it running for the first few seconds. GD Quote Link to comment Share on other sites More sharing options...
Phizinza Posted May 23, 2008 Share Posted May 23, 2008 Your IAC valve needs to be conneted to your intake pre MAF. This valve is on your pass side of the trottle body. IAC = Idle Air Control With the intake like that you will get a strange loud humming noise which may turn out to be a PITA like it was for me. It only goes away above 1500rpm or so. Quote Link to comment Share on other sites More sharing options...
Pooparu Posted May 23, 2008 Author Share Posted May 23, 2008 So if I found a way to hook all 4 of those lines up to that 6" pipe it should work right? You can't - on fuel injected engines the crankcase is part of the manifold vacuum system - that's how the PCV works, and the air circulateing through the whole system is metered by the MAF. It's a closed system and each of the little filters you added is a vacuum leak. A carburetor is what's known as a "demand feed" system. It's entirely dependant on manifold vacuum to "pull" in air and fuel. Fuel injection is not demand driven - the ECU introduces fuel based entirely on the air passing by the MAF sensor. Thus a closed system is needed or you are pulling air (past the rings, ect) from places other than through the MAF sensor. All those filters are supplying "unmetered" air to the engine and the ECU is cutting the fuel down based on an incorrect MAF signal - result being the engine dies from lack of fuel. The initial cold-start enrichment is the only thing keeping it running for the first few seconds. GD Quote Link to comment Share on other sites More sharing options...
Numbchux Posted May 23, 2008 Share Posted May 23, 2008 So if I found a way to hook all 4 of those lines up to that 6" pipe it should work right? with emphasis on "should". it'd definitely be an improvement. Quote Link to comment Share on other sites More sharing options...
Pooparu Posted May 23, 2008 Author Share Posted May 23, 2008 with emphasis on "should". it'd definitely be an improvement. Well I guess we'll see. I just need to find someone to custom make the part then I should be on my way. Quote Link to comment Share on other sites More sharing options...
rguyver Posted May 23, 2008 Share Posted May 23, 2008 Your IAC valve needs to be conneted to your intake pre MAF. This valve is on your pass side of the trottle body. IAC = Idle Air Control With the intake like that you will get a strange loud humming noise which may turn out to be a PITA like it was for me. It only goes away above 1500rpm or so. I agree its your IAC hose it needs to go in the intake pipe so the MASS air flow reads air flow . you should be able to get away with the cover filters but why risk durt getting in your engine when hose is cheep and it works . looks cool tho Quote Link to comment Share on other sites More sharing options...
Manarius Posted May 23, 2008 Share Posted May 23, 2008 The location of that filter is not really that great. You're sucking in hot underhood air through the cone. Definitely not an improvement from the airbox that at least gets air from the fender that's 40+ degrees cooler. I would suggest running a long smooth pipe from from the TB to inside the fender and put the cone there. Quote Link to comment Share on other sites More sharing options...
Pooparu Posted May 24, 2008 Author Share Posted May 24, 2008 The location of that filter is not really that great. You're sucking in hot underhood air through the cone. Definitely not an improvement from the airbox that at least gets air from the fender that's 40+ degrees cooler. I would suggest running a long smooth pipe from from the TB to inside the fender and put the cone there. I'm trying to accomplish 2 things. One, keep it from sucking up gobs of water when I'm hitting mud puddles and two keep it cooler. I wanted to add a hood scoop to help the cooler part out, but I need to figure out if this relocation thing is going to work before I go cutting a hole in my hood and adding a scoop. I'll just put it back to stock until I can get a pipe made. It's not a big deal right now. Quote Link to comment Share on other sites More sharing options...
Gloyale Posted May 24, 2008 Share Posted May 24, 2008 Any ideas on why, and how can I make this work? If you plug the PCV and put the filter over the IAC line it would work. But you'd have no real *ventilation* of the crankcase other than the *breather* filters. Quote Link to comment Share on other sites More sharing options...
subaru360 Posted May 24, 2008 Share Posted May 24, 2008 You can leave the two breathers on the valve covers alone if you want and plug the other hose off. But the big hose to the IAC needs to be plumbed back into the pipe you have after the MAF sensor. The IAC is pulling unmetered air, that's why it won't idle. Quote Link to comment Share on other sites More sharing options...
zukiru Posted May 25, 2008 Share Posted May 25, 2008 side note the EJ looks nice and stock! good work! Quote Link to comment Share on other sites More sharing options...
kingbobdole Posted May 27, 2008 Share Posted May 27, 2008 +1 on the IAC having to be hooked up to the intake AFTER he MAF but before the throttle body. Deleting the PCV system is a bad idea. Quote Link to comment Share on other sites More sharing options...
Pooparu Posted May 27, 2008 Author Share Posted May 27, 2008 +1 on the IAC having to be hooked up to the intake AFTER he MAF but before the throttle body. Deleting the PCV system is a bad idea. I think I'll have a 6" pipe made and have nubs to hook all the hoses back up. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.