Really BAD Gas Mileage
03-03-2007, 01:58 PM
#44
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Dude if you dont' have a multimeter and dont' even know which one you would need you should take that truck to a shop now and save yourself some trouble. Did they bother to pull the code during the diagnostics test that was mentioned? I'm guessing it had nothing to do with that EGR valve.
Yeah that was a smart ass comment...we're here to help one another not take pot shots. I'll apologize for him !!
I get really bad mpg too, I've replaced a LOT of stuff but I have some performance mods too so there is no telling. I do unplug the cold start injector I think mine is intermittent (on all the time sometimes), so I plug it up on cold mornings then unplug it the rest of the time.
03-03-2007, 03:44 PM
#45
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I get really bad mpg too, I've replaced a LOT of stuff but I have some performance mods too so there is no telling. I do unplug the cold start injector I think mine is intermittent (on all the time sometimes), so I plug it up on cold mornings then unplug it the rest of the time.
Do you notice a difference from doing this?
What size is the tank then?
03-06-2007, 02:05 PM
#46
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I have replaced the TPS and now I am trying to set it but according to this FSM page it says I need thickness gauges which I don't have yet. The two test that do not require the gauges (throttle valve all the way closed and then all the way open) I have done and they read fine. However our problem now is not when the throttle valve is all the way closed or open. The problem is when RPMs are around 2k, the RPMs will bounce/surge/go up and down.
Also the throttle cable was a little too tight and wouldn't let the valve close all the way without just a little force. I fixed that and still nothing.
Anyone have any advice?
Also the throttle cable was a little too tight and wouldn't let the valve close all the way without just a little force. I fixed that and still nothing.
Anyone have any advice?
03-06-2007, 05:03 PM
#47
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You have got to set the TPS. "Pep Boys" around here had all the feeler gauges I needed. Don't bother doing anything else until you have the TPS set. Did you adjust the TPS while installing per the FSM. IT is very important!!!!
Just pm if you have any questions.
Just pm if you have any questions.
03-07-2007, 11:14 AM
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cant help but rebring it up, the gas tank, if 15 is small, then what should it b? i know on my 94 4cyl 2wd 22re pickup its about a 12 gallon tank. between 10 and 12. i wish i had a 15, but then again, its nice to fill to the brim from e with 25 bucks eh?
03-07-2007, 11:30 AM
#51
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Ok, so not to confuse anyone... this is my truck, but as you can tell my boyfriend is doing a lot of the work on it and I am just helping. 
The tank I thought was a 15 because I usually put in more than 14 gallons when it's on E. I heard that I should be getting anywhere from 18-22 mpg and I am getting around 9.
I did try unplugging the CSI and that is working just fine since it was harder to start once it was unplugged.
Like Colton (my bf) said, he replaced the TPS and still needs to work on setting it.
However, today when I was driving it all of a sudden it felt like the truck was sputtering. It was running really rough and you could hear it like something was really backed up. RPM's would go from 3000 to like 1800 in a split second and now it is running like this constantly. We really need to check the vacuum lines but outside of that would this point anyone in a new direction as to what could be wrong?
Here is exactly EVERYTHING that is going on (so you don't have to keep re-reading other posts):
-At idle when I apply breaks, RPM fluctuates from 700-2000 RPM
-Release brake pedal and idle sits around 2000 RPM (most times)
-May drop down as low as 500 RPM at times
-Around 2000 RPM, when driving, I feel the and hear that surging again
-As of today, now I get major sputtering and ROUGH ride
-Has been running rich
-Getting around 9 mpg
-TPS replaced, EGR replaced, cat removed, engine seafoamed, complete tune-up, 02 sensor replaced
So from that info is anyone thinking it could be an injector (the rough idle)? And I know I had the EGR unit replaced but there are multiple parts to the EGR so could there be something with the EGR system that is causing the bad mileage?
Thanks guys... you are A LOT of help!
The tank I thought was a 15 because I usually put in more than 14 gallons when it's on E. I heard that I should be getting anywhere from 18-22 mpg and I am getting around 9.
I did try unplugging the CSI and that is working just fine since it was harder to start once it was unplugged.
Like Colton (my bf) said, he replaced the TPS and still needs to work on setting it.
However, today when I was driving it all of a sudden it felt like the truck was sputtering. It was running really rough and you could hear it like something was really backed up. RPM's would go from 3000 to like 1800 in a split second and now it is running like this constantly. We really need to check the vacuum lines but outside of that would this point anyone in a new direction as to what could be wrong?
Here is exactly EVERYTHING that is going on (so you don't have to keep re-reading other posts):
-At idle when I apply breaks, RPM fluctuates from 700-2000 RPM
-Release brake pedal and idle sits around 2000 RPM (most times)
-May drop down as low as 500 RPM at times
-Around 2000 RPM, when driving, I feel the and hear that surging again
-As of today, now I get major sputtering and ROUGH ride
-Has been running rich
-Getting around 9 mpg
-TPS replaced, EGR replaced, cat removed, engine seafoamed, complete tune-up, 02 sensor replaced
So from that info is anyone thinking it could be an injector (the rough idle)? And I know I had the EGR unit replaced but there are multiple parts to the EGR so could there be something with the EGR system that is causing the bad mileage?
Thanks guys... you are A LOT of help!
03-07-2007, 11:52 AM
#52
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Sounds like a vacuum leak. Since BRAKES are vacuum assisted.
You can try using some starting fluid to find the leak. Use a nozzle w/ a lil red tube and after starting the truck, start spraying around slowly. If your RPM's shoot up the leaks around there.
Check those areas that get hot, coming off the intake manifold. Also around the injectors, bad Oring seals?
From looking around it seems vacuum leaks are VERY common on 4runners.
Especially w/ all those damn hoses, at least on my 3.slo
You can try using some starting fluid to find the leak. Use a nozzle w/ a lil red tube and after starting the truck, start spraying around slowly. If your RPM's shoot up the leaks around there.
Check those areas that get hot, coming off the intake manifold. Also around the injectors, bad Oring seals?
From looking around it seems vacuum leaks are VERY common on 4runners.
Especially w/ all those damn hoses, at least on my 3.slo
Last edited by Schralper; 03-07-2007 at 11:53 AM.
03-07-2007, 02:32 PM
#53
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TPS has been replaced along with the catalytic converter and the idle is still the same. Performance has boosted a little bit and we are waiting to see the results of the gas mileage. Things we have left to try are the IAC and...?
Forgot to mention, the idle only bounces when the brake is depressed.
Forgot to mention, the idle only bounces when the brake is depressed.
Oh, sorry, see where you checked sticking butterfly. Lower the idle, check brakes though.
Last edited by JEBSR5; 03-07-2007 at 02:36 PM. Reason: detail missed.
03-07-2007, 05:19 PM
#55
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You mentioned above where idle only bounces when the brake is depressed.
This is caused by idle being above 1000RPM. Lower idle to below 1000RPM and this will stop bounce.
03-08-2007, 05:31 AM
#56
Contributing Member
Here is the latest;
The truck not sputters horribley throughout the whole RPM range.
I pulled the Spark Plug Wire on cylinder one and it ran no different. I plugged it back in and unplugged #2, then #3, and finally #4, and it ran horrible, like it should. So I am beginning to thing something is wrong in Cylinder #1. The spark plug is good however they are not Denso, they are Champion. The wires are good.
Could it be an injector?
The truck not sputters horribley throughout the whole RPM range.
I pulled the Spark Plug Wire on cylinder one and it ran no different. I plugged it back in and unplugged #2, then #3, and finally #4, and it ran horrible, like it should. So I am beginning to thing something is wrong in Cylinder #1. The spark plug is good however they are not Denso, they are Champion. The wires are good.
Could it be an injector?
03-08-2007, 06:43 AM
#57
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03-08-2007, 10:31 AM
#59
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Ran the self diagnostic check posted by 4crawler.
The check engine light flashed this;
...II...IIIII...
In my Haynes manual is says;
System;
Air-Fuel Ratio
Lean
Malfunction
Trouble area;
-Injector circuit
-Injector
-Fuel line pressure
-Ignition System
-O2 Sensor circuit
-02 Sensor
-Air Fuel Meter
-Water temp. Sensor
-ECU
According to everything stated above, today I am going to test the injector on cylinder #1.
The check engine light flashed this;
...II...IIIII...
In my Haynes manual is says;
System;
Air-Fuel Ratio
Lean
Malfunction
Trouble area;
-Injector circuit
-Injector
-Fuel line pressure
-Ignition System
-O2 Sensor circuit
-02 Sensor
-Air Fuel Meter
-Water temp. Sensor
-ECU
According to everything stated above, today I am going to test the injector on cylinder #1.
