gas milage after vacrac/emissions removal
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gas milage after vacrac/emissions removal
ok not long ago i had my uim and what not off and decided to remove all of my emisons equipment. will this effect my gas milage? cause it seems like i am burning for gas than usual. Maybe my secondary injectors are stuck open or something? i dunno but it sure does use alot of gas. more than before it seems. any one else have gas milage troubles after removing all of their emisions equip? any and all help would be great. . thanks.
Dom
Dom
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if anything your gas mileage should improve. Perhaps while you were poking around in there you hit the wire to the 02 sensor? It gets very brittle because of the heat and just hitting it could break it. That would decrease your fuel economy slightly.
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no my 02 sensor is still hooked up. if the o2 wire was off wouldn't i throw a code anyhow? i feel as though my secondaries are stuck open or something. i disconected the injector plugs tonight before a 25 mile drive and the gas milage seemed to be better tahn before. where should i run the vaccum line that goes into the secondary fuel rail to? i have it going to the drivers side of the dynamic chamber. . the only 1/4 inch vaccum nipple there. should i have it running to somewhere else? help would be great guys. gas is killin me. . lol thanks for any help.
Dom
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You getting any symptoms of a cat clogging? Hitting a wall at 4K, that kind of thing? Did you make sure a good vac source is going to the FPR?
You can read out the O2 sensor from the ECU and see how rich you're running from there, also...
You can read out the O2 sensor from the ECU and see how rich you're running from there, also...
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i don't ahve cats. and no i'm not hitting a wall at 4k. well i am but that's cause i just unplugged my secondaries to see if that would help
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#8
Originally Posted by Dom_C
no my 02 sensor is still hooked up. if the o2 wire was off wouldn't i throw a code anyhow? i feel as though my secondaries are stuck open or something. i disconected the injector plugs tonight before a 25 mile drive and the gas milage seemed to be better tahn before. where should i run the vaccum line that goes into the secondary fuel rail to? i have it going to the drivers side of the dynamic chamber. . the only 1/4 inch vaccum nipple there. should i have it running to somewhere else? help would be great guys. gas is killin me. . lol thanks for any help.
Dom
Dom
oh damn sorry wayne didn't see you already wrote that.
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I think you need to get a fuel pressure gauge (don't we all, lol), see what your pressures are, and if too high find another vac source for the FPR. I'm thinking you're running as if in the hot start assist mode (37 psi) all the time, because of the FPR's vac source (or lack of vac)...
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Originally Posted by powrdby13B
ya... check ur afr... injectors might be maxin out all the time...
does it smell like gas or **** while its running (more than usual)?
does it smell like gas or **** while its running (more than usual)?
^--- lol.... smells like gas or ****.... either gas, or ****, or whatever else those goddamn rotary shitholes burn and pump out the grapefruit launcher ricerboys put on those damn import POS's....
wow, sorry. just got hyper and felt like saying that.
ROTARY POWER!!
-Andrew-
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yea it does smell like gas more than normal. how would i stop it from running in hot start assist? i have absolutly no emisions equipment left onthe car. where is a good spot to hook up the fpr vac line? i've tried two stops with no difference. on on the front side of the dynamic chamber and the other on the drivers side of the dynamic chamber. i disconnected my secondaries and have seen a dramatic increase in gas milage so there must be some problem there. . if anyone has any ideas on how to remady this please let me know. thanks
Dom
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the middle of th lim. . ok i'll try that on out. i think that's where i have me pressure sensor line going to though. i'll check it out. thanks though oh yea if anyone else has some ideas please let me know.
Dom
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You can keep switching "vac" sources, Honda Dude may have given you a good spot there, but you're just shooting in the dark until you know for sure with a fuel pressure gauge (a cheap temporary gauge that can be "T'd" in to the supply line should work well). Remember, this is just a theory at this point...
#17
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Originally Posted by Dom_C
where should i run the vaccum line that goes into the secondary fuel rail to? i have it going to the drivers side of the dynamic chamber. . the only 1/4 inch vaccum nipple there. should i have it running to somewhere else? help would be great guys. gas is killin me. . lol thanks for any help.
Dom
Dom
The fuel pressure regulator solenoid is there for a reason. The fuel pressure regulator does NOT see vacuum at all times. Deleting the solenoid and hooking the FPR vac line to the manifold will cause the FPR to restrict fuel pressure at all times. Hence you have elevated fuel pressure at idle and cruising speeds.
Re-install the FPR solenoid.
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I don't agree with most of that- the PRC soleniod only energizes for hot start applications, when the dynamic chamber air temp sensor is sensing 176*F & over (between 1 & 2v inputed to the ECU). At all other times it is de-energized, allowing manifold pressures (mostly vac) to help regulate the FPR spring & diaphragm movements. See the FSM, page 4A-80, and 4A-7 (S4)...
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Orange on the S4's. I said this before on another post, but I was tracking mine one day at the ECU, and even on a 98*F day here in Houston, and letting her heat soak a bit after a long drive, she still wasn't hot enough to kick in the hot start system on the next start, so I know it doesn't get used very often...
#21
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Originally Posted by wozzoom
You people are killing me with your "all and nothing" approach to vacuum spider removal. You don't even know what you are removing...
The fuel pressure regulator solenoid is there for a reason. The fuel pressure regulator does NOT see vacuum at all times. Deleting the solenoid and hooking the FPR vac line to the manifold will cause the FPR to restrict fuel pressure at all times. Hence you have elevated fuel pressure at idle and cruising speeds.
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[QUOTE=NZConvertible]I totally agree with you on that, but in this case, neither do you...[QUOTE]
I got it. The wording the the FSM had me confused when I glanced at it... For some reason I thought that the FPR only saw vac during the hotstart conditions and not the other way around. Thanks for setting me strait.
I got it. The wording the the FSM had me confused when I glanced at it... For some reason I thought that the FPR only saw vac during the hotstart conditions and not the other way around. Thanks for setting me strait.
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IMHO you all are obsessed with the FPR. You really need to take another tack. Idle your engine and warm it up. Pull the vac hose off the pressure/boost sensor. Do you have vaccuum at that vacuum hose?? Is the electrical plug connected? I ask because you know that normally the secondary injectors will not come on until there is a LOAD on the engine and the rpm is over 3500 rpm. They don't come on every time the rpm is over 3500rpm. It's rpm and LOAD. Load as detected by the pressure sensor seeing atmospheric pressure, or MAYBE in your case.......no vacuum at the boost/pressure sensor because the vac hose ain't connected to a vac source or the electrical plug is off. Sorta a long way of saying if there isn't vac there....then the secondary injectors will come on each and every time the rpms are over 3500......wasting gas I suppose. Then again, it could be another thing all together.
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The other thing could be the waterthermo sensor on the back of the water pump housing.....as mentioned in a post above. No connection means the ECU defaults to a preset temp, I think 86 degrees ...or was it 186??? one or the other. Makes the engine run in the Not Efficient Range.