Well you may know that I was doing a little test on an intake that I bought for $50. Also I installed a 4.0 TB. So I was running the 4.0TB, Intake and a TB spacer that came with the jeep. Let me say first off I don't know if it was just something I did but the jeep ran like sh*t after the install. Revving to 2000 rpms in between shifts. It was really bugging me. Also it felt like I was getting too much air (yes that sounds retarded) but it felt like that. So last night I decided to put back on my stock air box. The person before me had installed a mini snorkel on it and I just re-sealed it and wanted to show you another way it can be done.
Now that I have the stock air box back on the jeep runs like it used to. Also I noticed that I would always be in higher rpms because I wanted to hear the intake so I am glad I took it off.
I was thinking of trying my stock air box again, mainly for the fact that I was getting a check engine light and the computer code was for a faulty 02 I replaced the 02 and I am still getting the code. Does anyone know if this could be the cause? Actually I dont feel any difference in performance. Also the CCV tube and that Evaporative cannister tube no longer run anywhere which I dont see that being a major problem, although maybe these lines need some vacum, to give the right readings to the computer. I was thinking of tapping a cople holes in the tube for these lines. I suppose that would either eliminate the problem or at least put everything back where it belongs.
If you increase your intake airflow you must also increase your exhuast. Your engines preformance won't go up much just on an intake alone and may run worse. Also there are two house that go into your airbox, were these accounted for?
I put in an intake system and didn't notice a big difference in preformance untill I installed my new exhaust system. It's important for your engine to have as much air in as it can handle going out.
If you increase your intake airflow you must also increase your exhuast. Your engines preformance won't go up much just on an intake alone and may run worse. Also there are two house that go into your airbox, were these accounted for?
I put in an intake system and didn't notice a big difference in preformance untill I installed my new exhaust system. It's important for your engine to have as much air in as it can handle going out.
Finally! You tell people this sort of thing and they look at you like you're crazy. I made an intake for my 4.0 (3" pvc and a cone filter) and really didnt notice a difference, except for the sound, I recently put a 2.5" magnaflow cat-back on, and the intake really compliments the exhaust.
If you increase your intake airflow you must also increase your exhuast. Your engines preformance won't go up much just on an intake alone and may run worse. Also there are two house that go into your airbox, were these accounted for?
I put in an intake system and didn't notice a big difference in preformance untill I installed my new exhaust system. It's important for your engine to have as much air in as it can handle going out.
I upgraded the exhaust awhile back to a striaght through Dynomax Ultra Flo. That is the only reason that I added a Rock-It Air tube. I mentioned that I didnt have the CCV or the Evaporative cannister hooked up. There are no ports in this intake for them. I was thinking of tapping a couple. Although I really dont think that this is the whole problem, to the 02 sensor code. It could probably attribute to a good deal of it, you figure that the gases that are not going to the evaporitive cannister could be affecting the computer reading to the 02. I cant see that these gases just wouldnt exscape on their own into the air though. I was just thinking that between the exhaust and the intake that maybe the engine is running too rich thus the 02 code.
??? I added an ait intake tube. and a throttle body spacer. I didnt mess with any sensors. They are all still intact. The only trouble code that I was getting was for the 02 sensor and I replaced that and still get the same code. I think that since the intake is sucking in more air it is probably screwing with the computer and causing it to run rich. It passed emissions like this and the test is the same as California`s. I think my best bet is to just hook up everything stock and see what happens.
I thing that I havent ever found on a Jeep is the computer, awhile back someone told me to look for I believe they said to see if there is voltage at pin 11 0r 12. If I remember right I think that they said that there should not be any there.
I will dig back through my posts to see if I can find this info.
??? I added an ait intake tube. and a throttle body spacer. I didnt mess with any sensors. They are all still intact. The only trouble code that I was getting was for the 02 sensor and I replaced that and still get the same code. I think that since the intake is sucking in more air it is probably screwing with the computer and causing it to run rich. It passed emissions like this and the test is the same as California`s. I think my best bet is to just hook up everything stock and see what happens.
I thing that I havent ever found on a Jeep is the computer, awhile back someone told me to look for I believe they said to see if there is voltage at pin 11 0r 12. If I remember right I think that they said that there should not be any there.
I will dig back through my posts to see if I can find this info.
I may be wrong but it sounded like you did a TB swap from a 4.0 engine. If so you need to use the sensors off your 2.5 engine TB and put them on the 4.0 TB. If you had a emissions done and passed the CA system you are running good.
Be careful when you probe for voltage and Ohm on computers, you can do damage, its best for the tech to do it. I know alittle about this, I am a CA smog Tech.
I put on a 4.0L TB, 62mm spacer, bored out the intake manifold, and put on a high flow intake. It runs great now and has some nice power. The engine seems smoother and has a cool sound to it now. I have no exhaust modifications and I used the 4.0L sensors, and everything seems to work fine. At first my idle was at about 1500 RPMs, but after I reconnected this one hose that I had accidentally broke, its down to about 900 which was about normal with the 2.5L (maybe 50 Rpms faster).
I installed a K&N Air Intake (ebay $225 shipped special) and PowerAid Throttle Body Spacer and didn't notice much difference either. I also have a Flowmaster 40 series exhaust on mine. There probably is a bit of difference, I just can't feel it and I haven't driven it enough yet to determine if it helps with gas mileage.
HOWEVER.... It does look pretty cool and I love to hear the air getting sucked into the motor. So mentally, it's a good upgrade. :thumbsup:
I may be wrong but it sounded like you did a TB swap from a 4.0 engine. If so you need to use the sensors off your 2.5 engine TB and put them on the 4.0 TB. If you had a emissions done and passed the CA system you are running good.
Be careful when you probe for voltage and Ohm on computers, you can do damage, its best for the tech to do it. I know alittle about this, I am a CA smog Tech.
Actually I did was remove the stock airbox the same one at the top of the photo and add an air tube, with a K&N filter. There was a tube that runs from the evaporative cannister to the airbox which is now dissconnected and the CCV (Crankcase Ventalation)
About checking voltage on computers I have done this many a time you need to rid yourself of static electricity. Shock yourself :laugh: Its the truth. They sell ground clips that will ground you to something so that the energy goes where it is directed instead of through your hands to the computer you are working on. All they really are is alligator clips and a piece of wire. Then another thing that you can use static spray. It isnt really as scary as people make it seem. Just think of all the people that put in computer chips that dont probably even follow these steps.
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