EBAY intake for fun= got Check Engine light on...help?
04-14-09, 05:07 AM
#16
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I made a DIY intake for my GS400 using spare parts I had laying around. I used a 3" 90 elbow (left over from my friends turbo build) off the throttle body and cut up an ebay intake made for a GS300 to use the MAF mount. I slapped a 3" air filter in front and it has worked fine for months with no CEL. The GS300 intake pipe I used had a vacuum fitting after the meter so I used that for the vacuum. Just measure the inner diameter of the pipe where the mount for the meter is. If the inner diameter is the same in the factory air box as it is in the intake you should be good to go. I think the stock MAF mount is about 3". If youe eBay intake is 3.5" or 2.5" it is going to through a CEL because the meter isnt reading the correct percentage of air.
Last edited by KiPod; 04-14-09 at 05:10 AM.
04-14-09, 05:52 AM
#17
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I made a DIY intake for my GS400 using spare parts I had laying around. I used a 3" 90 elbow (left over from my friends turbo build) off the throttle body and cut up an ebay intake made for a GS300 to use the MAF mount. I slapped a 3" air filter in front and it has worked fine for months with no CEL. The GS300 intake pipe I used had a vacuum fitting after the meter so I used that for the vacuum. Just measure the inner diameter of the pipe where the mount for the meter is. If the inner diameter is the same in the factory air box as it is in the intake you should be good to go. I think the stock MAF mount is about 3". If youe eBay intake is 3.5" or 2.5" it is going to through a CEL because the meter isnt reading the correct percentage of air.
but guys i honestly have no time and for like two weeks to do this so if i keep driving like this will anything bad happen to the car?
04-14-09, 10:29 AM
#19
You can use the method Kipod is talking about to trick the ecu, you wont get quite as much power as a intake/AFC combo due to the fact you are flowing less air but you will still get a gain from smoother piping etc...
If you want something just quick and dirty you could even go to the plumbing section of Home Depot and get a rubber coupler for plumbing. This is kind of ghetto but if you just want to play with pipe diameters etc... then i will work just fine. What you want to do is reduce the pipe diameter going into the MAF to roughly the size of the stock intake as Kipod mentioned. It may take a little creativity but yo can make it work, if not SRT sells the complete kit with everything you need to make some good power
If you want something just quick and dirty you could even go to the plumbing section of Home Depot and get a rubber coupler for plumbing. This is kind of ghetto but if you just want to play with pipe diameters etc... then i will work just fine. What you want to do is reduce the pipe diameter going into the MAF to roughly the size of the stock intake as Kipod mentioned. It may take a little creativity but yo can make it work, if not SRT sells the complete kit with everything you need to make some good power
04-14-09, 10:51 AM
#20
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Yeah, you should always make more power with some sort of fuel / timing control device to set the tune. I just wanted to get that huge air box out of the engine compartment.
I just wasn't trying to pay for an intake.
Last edited by KiPod; 04-14-09 at 12:09 PM.
04-14-09, 10:52 AM
#21
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macd. i totally get you bro!
i have a short ram intake (Weapon R) in my GS400 with no piggyback or AFC and i have no problems. its been on for well over two years. i do floor it on occasion merging onto the highway. OP, some things you can do are reset your ECU, check that wires going into MAF are intact, and clean your MAF. maybe it sucked in oil from your filter and its throwing off the reading.
i have a short ram intake (Weapon R) in my GS400 with no piggyback or AFC and i have no problems. its been on for well over two years. i do floor it on occasion merging onto the highway. OP, some things you can do are reset your ECU, check that wires going into MAF are intact, and clean your MAF. maybe it sucked in oil from your filter and its throwing off the reading.
04-14-09, 12:54 PM
#22
Thanks man!
Yes and no, you can get the same amount of air through a small pipe at a higher velocity up to a point. The engine is only creating so much vacuum so as long as the pipe diameter isn't causing a hindrance at that vacuum level then a 3" pipe should be as good as a 4" pipe.
For instance, if you had a 4" pipe and a 1" pipe, the 1" pipe could flow the same volume as the 4" pipe up to a certain point. The car is producing a certain amount of vacuum at a given rpm. If the amount of vacuum at this rpm isn't enough to force air (technically draw air through the pipe) through the 1" pipe at a rate fast enough to match the 4" pipe then that's where your issue will be.
The question would boil down to, exactly how much air is the stock intake flowing after losses (turbulence, friction etc..) and how much can a same sized metal pipe flow. The elimination of the factory "ribbing" and use of a smoother material (assuming the factory pipe has a coefficient of friction greater than the aftermarket pipe, I didn't have time to look them up right now) would allow a higher flow at the same vacuum levels.
From there is where it would get interesting as you could take that information and find out if you are having an appreciable loss by using a factory sized intake pipe (even though it's smooth) compared to a 4" intake pipe (of the same material). There would be a rise in friction due to the increased surface area of the 4" pipe but it may be negligible because of the physically increased flow ability by increasing the diameter.
While it is apparent from informal testing that there are gains to be had by increasing flow (suggesting the factory intake pipe is causing a restriction) the question is where is the point where you will reach the point of diminishing returns. From past data we know that a 3" smooth pipe increases flow compared to the stock intake pipe and that going larger than that causes a CEL.
Is the limit on performance caused by the engine being able to draw in more air than the 3" pipe is able to support at the max vacuum or is it just because of the MAF not being calibrated correctly for a larger diameter pipe? Point being it would be interesting to compare a car with a 4" intake (arbitrary diameter) compared to a car with a 3.5" intake (also arbitrarily chosen) to see where the point of diminishing returns is reached. For instance maybe a 3.1" diameter pipe is all that's needed to meet the max requirements of the engine in "stock" form? Unfortunately they generally don't make pipes in small increments but it would be interesting to find the exact max diameter of pipe you could get away with using on the stock maf and no A/F management compared to a large pipe with an AFC. Possibly there are no gains to be had by using a 4" pipe over a 3.25" pipe (assuming you have fuel management).
I have to run but I'll try to edit this post for clarity later this evening.
For instance, if you had a 4" pipe and a 1" pipe, the 1" pipe could flow the same volume as the 4" pipe up to a certain point. The car is producing a certain amount of vacuum at a given rpm. If the amount of vacuum at this rpm isn't enough to force air (technically draw air through the pipe) through the 1" pipe at a rate fast enough to match the 4" pipe then that's where your issue will be.
The question would boil down to, exactly how much air is the stock intake flowing after losses (turbulence, friction etc..) and how much can a same sized metal pipe flow. The elimination of the factory "ribbing" and use of a smoother material (assuming the factory pipe has a coefficient of friction greater than the aftermarket pipe, I didn't have time to look them up right now) would allow a higher flow at the same vacuum levels.
From there is where it would get interesting as you could take that information and find out if you are having an appreciable loss by using a factory sized intake pipe (even though it's smooth) compared to a 4" intake pipe (of the same material). There would be a rise in friction due to the increased surface area of the 4" pipe but it may be negligible because of the physically increased flow ability by increasing the diameter.
While it is apparent from informal testing that there are gains to be had by increasing flow (suggesting the factory intake pipe is causing a restriction) the question is where is the point where you will reach the point of diminishing returns. From past data we know that a 3" smooth pipe increases flow compared to the stock intake pipe and that going larger than that causes a CEL.
Is the limit on performance caused by the engine being able to draw in more air than the 3" pipe is able to support at the max vacuum or is it just because of the MAF not being calibrated correctly for a larger diameter pipe? Point being it would be interesting to compare a car with a 4" intake (arbitrary diameter) compared to a car with a 3.5" intake (also arbitrarily chosen) to see where the point of diminishing returns is reached. For instance maybe a 3.1" diameter pipe is all that's needed to meet the max requirements of the engine in "stock" form? Unfortunately they generally don't make pipes in small increments but it would be interesting to find the exact max diameter of pipe you could get away with using on the stock maf and no A/F management compared to a large pipe with an AFC. Possibly there are no gains to be had by using a 4" pipe over a 3.25" pipe (assuming you have fuel management).
I have to run but I'll try to edit this post for clarity later this evening.
Last edited by macd7919; 04-14-09 at 12:58 PM.
04-14-09, 01:02 PM
#23
Ebay intakes give off CEL's...check the CEL. Also check to make sure all the hoses leading into the intake are secured tightly.
My problem with the ebay intake was the fuel vapor line, and it was causing my fill ups to be problematic, clicking off the pump thinking the tank was full, but it was not.
It also threw a CEL, aside from the fuel vapor hose, I don't know what else. It didn't affect anything as far as driving, and the cell didn't come on until a month after I had it in the car.
Another thing you can do is what this one member did, by using his stock airbox (seems where the problems arise with ebay intakes) and an aftermarket intake pipe, cutting the pipe down to size to fit the airbox.
My problem with the ebay intake was the fuel vapor line, and it was causing my fill ups to be problematic, clicking off the pump thinking the tank was full, but it was not.
It also threw a CEL, aside from the fuel vapor hose, I don't know what else. It didn't affect anything as far as driving, and the cell didn't come on until a month after I had it in the car.
Another thing you can do is what this one member did, by using his stock airbox (seems where the problems arise with ebay intakes) and an aftermarket intake pipe, cutting the pipe down to size to fit the airbox.
04-14-09, 04:18 PM
#27
04-14-09, 09:45 PM
#30
There is also a disadvantage to changing from plastic oem to metal intake, and that is the extra heat that metal piping will soak.
I wish everyone with a different intakes could dyno back to back the same completely stock vehicle with all the different intake available, even customes. This way we can put this issue to rest and find which ones are truely worth buying.
I wish everyone with a different intakes could dyno back to back the same completely stock vehicle with all the different intake available, even customes. This way we can put this issue to rest and find which ones are truely worth buying.
Last edited by GS FONZy; 04-14-09 at 09:50 PM.