What is the port on the bottom of the Evap canister supposed to hook to? I have three hoses on the top and nothing is connected to the bottom of the canister, or is it a vent? My EGR valve never moves. I took it off, cleaned it out and tested it again but it still doesn't move with the engine hot and revving it up. My catalytic converter has been cut off and straight piped. I am getting about 10 miles a gallon and I want to improve that. I ordered a new catalytic converter to put back on. Also my fuel pump is oily around it, and there is a port on the bottom portion of the fuel pump that has a hose on it and it is just dangling down, is this just a vent also? The engine runs great and spark plugs are chocolate brown but I am just getting horrible mileage.
the ports on the bottoms of the canister and the pump are vents/drains. Nothing should be coming out of them but air.
The EGR valve needs several things in order for it to work. It's not something you can just gun the engine and watch it pop open.It needs the EGR modulator, it needs the temperature sensor/bimetal vaccum switch, and it needs the vacuum switching valve on the back of the carb next to the EGR modulator. All of those parts need to be in working order and need to be hooked up correctly to the appropriate vacuum lines and electrical connectors. When that happens, Your EGR valve will be drawn open by the manifold vacuum and exhaust will be drawn through it. The conditions necesary for this to happen would be your RPM's would need to be above 2800 (I think) your intake manifold temperature would have to be hot enough to open the BVSV, the back pressure in your exhaust would need to be high enough to open the EGR modulator.
Can you define bad gas mileage? What size tires are you running and are you sure that all of your vaccuum lines are fresh rubber and are hooked up to the correct ports?
I am getting around 10 miles a gallon. I fill up around 107 to 110 miles on a tank. I used to fill up at 160 miles on a tank so I was getting around 16 miles a gallon if my odometer is correct. I am running 32 x 11.50. I replaced all the vacuum lines sprayed around all of them with carb cleaner with engine running to check. Also my idle won't come below 1100 rpm's. I took one of the top hoses off the modulator and the harder I revved the engine the more it sucked. The big hose on the bottom of the modulator had no suck. I left the big hose that connects the modulator to the egr hooked on the egr and sucked on it with my mouth as hard as I could with engine at idle and nothing happened. When I manually push in the egr valve with all hoses connected, nothing changes it idles as normal. When I disconnect hose connecting modulator and egr valve and manually push egr valve in, the engine idles rough and tries to die. I have low gears in axles and also in transfer case so I realize I may not get 30 mpg but I would like to get back to my original 16 to 18 instead of the 10 mpg I am getting now. Also I looked on the bottom of the hood for the emissions routing and made sure all hoses were routed correctly.
If your running a stock transfercase with 32's and no one has swaped the the gearing for the speedo your running about 22% off on the reading. The 16 mpg will be closer to 19.5 when corrected for it. Your speedo will be reading about 12 mph off at 55 just showing about 43. If you press on the back of the EGR to open it while it's running and there is no change in the idol speed most likely the line is clogged from the valve to the intake manifold.
The EGR valve is pulled open by manifold vacuum that has passed through the BVSV, passed through the Modulator, and then passed through the TWSV next to the modulator. To open the EGR valve manually you just apply vacuum to the small hose on the front of the EGR that comes from the TWSV. The Large hose is to transmit backpressure to the Modulator. When the modulator opens the vacuum pathway to the TWSV so it can suck the EGR open, the EGR draws exhaust from the same port that the modulator is reading back pressure from. If you unplug the modulator hose, the EGR valve will suck large quantities of air (combustable) as opposed to small regulated quantities of exhaust gasses (innert) Sucking exhaust gasses enriches the mixture, sucking air leans out the mixture.
Your EGR system will not have a huge affect on your mileage. It will affect your NOX produced at high combustion temperature and it will cause your engine to run hotter than it would optimally. Not enough though to cut your fuel efficiency 50 percent.
Things to look at are your Plugs, O2 sensor, Cap and rotor, Coil, valve lash, If your Idle won't come down, you may have an issue with your high idle compensator. It kicks up the idle when the engine is under load from the alternator taking up a heavy load. If the Idle compensator is getting a faulty reading or is sticking open then your high idle plunger would be giving you problems at idle.
I have a '91 efi, but I keep my EGR blocked off for 51 weeks every year. Made a blocking plate from an old license plate. It is arranged like this - intake manifold, paper gasket, blocking plate, rtv, EGR. When it is time for the emissions test, I unbolt the EGR, clean off the rtv, and bolt it back up without the blocking plate.
And since the EGR is supposed to be closed when in 5th gear and I spend at least 80% in 5th gear, I have just removed a potential problem from the loop. You still need to make sure that the vacuum lines and such are still in good condition as the modulator will still function normally, the blocking plate just will not allow an exhaust gases into the intake manifold.
If you EGR value is stuck open, the blocking plate will stop what is essentially a big vacuum leak. Also replace your PCV if it hasn't been done recently.
I have a 4:16 crawler transfer case from RRO and yukon 4.57 gears in the axles. One stupid thing I did about a year ago was I was under the samurai looking around and saw there was a hose dangling down attached to nothing so I looked all over the place and finally found a place to put it. Well I attached the vent hose on the fuel pump to the vent spout on the bottom of the evap canister. I unplugged it yesterday and a bunch of gas came out the bottom of the canister, so I assume that my evap canister and also my fuel pump were not venting correctly, would this affect my mileage and should I replace my fuel pump or charcoal canister?
that depends on where the fuel came from. If it was from your evap cannister then something is wrong with the tank vent, liquid fuel should not ever enter the cannister. If it was from your fuel pump (most likely was) the bottom vent allows the air to exit and enter as the diaphragm flexes in and out to pump the fuel. If there is a leak in the diaphragm then fuel will leak out the vent pipe. When this happens it's time to replace the pump and to replace your oil. If fuel got past the diaphragm it can be dumping in your engine oil and wreaking havoc with your internals. Change that oil ASAP and change the Pump. You may have just found part of what is causing your poor fuel efficiency.
Well I got my new fuel pump on and oil changed. I also replaced the distributor cap and rotor and put a new muffler and catalytic converter on it because the muffler I had was a flowmaster and it was way too loud for my liking and I had cut off the old catalytic converter. My fuel mileage has went from 10 back up to 19 mpg. I also found that one of my rear brakes was hanging up. My egr valve is still not working right and my idle is still high, about 800 when you start it but when engine gets hot climbs to about 1500 to 1800, what could be the problem there? Other than that the samurai runs better than ever and no more knocking in the engine from the fuel in the oil.
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