WHY do I get 12MPG?????
11-18-2008, 09:01 AM
#41
Well I don't know about that, i mean OD is 4th gear and in my old max i could easily notice the 1-2, 2-3,and then 3-4 and the lowest i got it to engage in 4th was at 25 under very light acceleration. 70-75 makes no sense to me....
Either way OD will low engine speed and raise mileage is the main point, obviously.
Either way OD will low engine speed and raise mileage is the main point, obviously.
Nissan has fairly late gear engagement on the trans, which explains why I did better on the minivan driving normally than I do going easy on the VQ.
11-18-2008, 10:09 AM
#42
I fill up at sam's club because I have a card for there and its generally cheaper. Sometimes I go to Cosco too. I put Lucas UCL with most of my fill ups. I only use premium which here in Utah is 91 octane.
About the idling thing. In the summer I do the same thing and the mileage has been much better.
I usually can get almost 500 mile to the tank doing 80+ mph on the free way. That is about 29 mpg
About the idling thing. In the summer I do the same thing and the mileage has been much better.
I usually can get almost 500 mile to the tank doing 80+ mph on the free way. That is about 29 mpg
11-18-2008, 07:48 PM
#44
. Also i dont see why the engine would be less efficient with o/d than overdrive off. If you going slow and not acceleration much at all your not going to lug the engine in a high gear or cause it to "hunt." If your in rapidly varying conditions like rush hour around town or something o/d off could be better but in general, I've never had a problem with it on. Even if you need a lower gear, its an auto itl take care of that..
11-18-2008, 08:48 PM
#45
guys, I ran into something new and unknown till now. My CEL would not illuminate when there are codes for some reason. I had a couple of mins before work and decided to check for codes since I never did that after I changed the KS. And to my surprise...... there was a code. it is 0407 which is Crank position Sensor (ref). I am not sure what the REF stands for but I haven't read the FSM yet.
Also on the way back from work I tried to test the CEL. When the key is ON the light comes on as it's supposed to.
What I did was pull over, turn the car off. I unpluged the MAF sensor and went back on my way home. The did go into the 'safe mode' and would not go over 2400 rpm but NO CEL???? I came home and the first thing was to check the codes again. To my surprise (another one) there was no code for the MAF. I only had the CPS code. I have tried this thing with unplugging the MAF before and the code came up.
I have no idea WTF is going on.
PLEASE HELP A BROTHER IN NEED!!!!!
Also on the way back from work I tried to test the CEL. When the key is ON the light comes on as it's supposed to.
What I did was pull over, turn the car off. I unpluged the MAF sensor and went back on my way home. The did go into the 'safe mode' and would not go over 2400 rpm but NO CEL???? I came home and the first thing was to check the codes again. To my surprise (another one) there was no code for the MAF. I only had the CPS code. I have tried this thing with unplugging the MAF before and the code came up.
I have no idea WTF is going on.
PLEASE HELP A BROTHER IN NEED!!!!!
11-18-2008, 09:01 PM
#46
after reading from the FSM I have to mention something that I have had as an issue and I think it is possible for that to be the reason for that code. It said that even with a bad battery the code can come up because the car does not crank consistently when starting.
I have had a cold morning start problem for a while. It is that I go in the car and try to start it and then if it does not start right up (which never happens in the morning) it bogs down and the lights on the dash dim. Also at night (and not only) when I put my foot on the brake I can see that my headlights dim a little. that happens every time there is a higher load on the electric system. I have had the light dimming problem since I bought the car last year but I never gave it much thought because it has never bothered me that much.
Another thing that the FSM said is about a bad starter which could not be my problem since mine is like 6 months old.
I have had a cold morning start problem for a while. It is that I go in the car and try to start it and then if it does not start right up (which never happens in the morning) it bogs down and the lights on the dash dim. Also at night (and not only) when I put my foot on the brake I can see that my headlights dim a little. that happens every time there is a higher load on the electric system. I have had the light dimming problem since I bought the car last year but I never gave it much thought because it has never bothered me that much.
Another thing that the FSM said is about a bad starter which could not be my problem since mine is like 6 months old.
11-19-2008, 07:52 AM
#47
Senior Member
iTrader: (7)
Join Date: Dec 2004
Location: Alexandria, VA, & Central Jersey
Posts: 2,647
bad starters can happen all the time. I've changed out 3 starters before i got a good one. 2 from pepboys, and finally gave up and went to napa. That one was good. So unless its brand new, the rebuilt ones can definately still give you problems even if its right out of the box.
How old is ur battery? Your headlights shouldn't dim as you step on the brake lights since your alternator is running. Maybe its your alternator not charging properly. Once the car is running, it should get most of the electrical power from the alternator, something seems fishy there. I might be wrong, but i'll let others correct me if i am.
I had a CPS problem recently with my ford minivan. It was due to the fact i did not use motorcraft spark plug wires. The bosch spark plugs wire i had bought was actually sending a signal through the engine that was getting picked up by the CPS that caused the sensor to be faulty in reality it wasn't. It might not be the case since you've said that you've used quality parts. But then again, i thought bosch was a quality part. Anyways, the CPS might have something to do with ur gas mileage. I suggest to get an actual scanner and scan for all the codes.
as far as your ecu goes, something must be wrong when u swapped since it's not detecting any codes. So at the point that you do get a scanner, you might not even pick up the engine codes cause the ecu is not throwing any.
How old is ur battery? Your headlights shouldn't dim as you step on the brake lights since your alternator is running. Maybe its your alternator not charging properly. Once the car is running, it should get most of the electrical power from the alternator, something seems fishy there. I might be wrong, but i'll let others correct me if i am.
I had a CPS problem recently with my ford minivan. It was due to the fact i did not use motorcraft spark plug wires. The bosch spark plugs wire i had bought was actually sending a signal through the engine that was getting picked up by the CPS that caused the sensor to be faulty in reality it wasn't. It might not be the case since you've said that you've used quality parts. But then again, i thought bosch was a quality part. Anyways, the CPS might have something to do with ur gas mileage. I suggest to get an actual scanner and scan for all the codes.
as far as your ecu goes, something must be wrong when u swapped since it's not detecting any codes. So at the point that you do get a scanner, you might not even pick up the engine codes cause the ecu is not throwing any.
11-19-2008, 08:19 AM
#48
Don't know about the battery. The starter is from O'Reily's in AR.
Most of what you said does not make sense to me for some reason.
I reset the ECU and now I am gonna wait to see if the code will come back. There is not point in checking with a code reader since I can check with the screw. the codes show up but stay as ghost.
Most of what you said does not make sense to me for some reason.
I reset the ECU and now I am gonna wait to see if the code will come back. There is not point in checking with a code reader since I can check with the screw. the codes show up but stay as ghost.
11-19-2008, 09:56 AM
#50
Junior Member
Join Date: Jan 2008
Location: Chicago, IL
Posts: 23
Since it sounds like you make a lot of short trips coupled with a colder climate, your car may not be running long enough to properly charge your battery. This could be especially true if your battery is getting old.
While this probably wouldn't directly cause your mileage issue, it's possible that it could explain some of the weirdness with your ECU.
If your CPS is bad (or the ECU thinks it's bad), then the ECU may have retarded the timing to some default setting, which is safer for the engine but leads to poor performance and efficiency. If I remember correctly, the same holds true just about anytime the CEL is on.
Not an expert by any means, but maybe some of these could be contributing factors. Someone suggested a 100 point inspection. As much as I hate to feed the dealership service beast my hardearned dollars, that may be the best way for you to get a definitive answer.
Good luck!
While this probably wouldn't directly cause your mileage issue, it's possible that it could explain some of the weirdness with your ECU.
If your CPS is bad (or the ECU thinks it's bad), then the ECU may have retarded the timing to some default setting, which is safer for the engine but leads to poor performance and efficiency. If I remember correctly, the same holds true just about anytime the CEL is on.
Not an expert by any means, but maybe some of these could be contributing factors. Someone suggested a 100 point inspection. As much as I hate to feed the dealership service beast my hardearned dollars, that may be the best way for you to get a definitive answer.
Good luck!
11-19-2008, 10:01 AM
#52
Since it sounds like you make a lot of short trips coupled with a colder climate, your car may not be running long enough to properly charge your battery. This could be especially true if your battery is getting old.
While this probably wouldn't directly cause your mileage issue, it's possible that it could explain some of the weirdness with your ECU.
If your CPS is bad (or the ECU thinks it's bad), then the ECU may have retarded the timing to some default setting, which is safer for the engine but leads to poor performance and efficiency. If I remember correctly, the same holds true just about anytime the CEL is on.
Not an expert by any means, but maybe some of these could be contributing factors. Someone suggested a 100 point inspection. As much as I hate to feed the dealership service beast my hardearned dollars, that may be the best way for you to get a definitive answer.
Good luck!
While this probably wouldn't directly cause your mileage issue, it's possible that it could explain some of the weirdness with your ECU.
If your CPS is bad (or the ECU thinks it's bad), then the ECU may have retarded the timing to some default setting, which is safer for the engine but leads to poor performance and efficiency. If I remember correctly, the same holds true just about anytime the CEL is on.
Not an expert by any means, but maybe some of these could be contributing factors. Someone suggested a 100 point inspection. As much as I hate to feed the dealership service beast my hardearned dollars, that may be the best way for you to get a definitive answer.
Good luck!
11-19-2008, 10:46 AM
#54
I think my major problem is the cold mornings and absolutely not enough time for warming up of the car.
With the CPS I am leaning towards a bad/old battery so far.
I will still have to check it out though.
11-19-2008, 11:50 AM
#55
What is your real location man? You could be anywhere with that laptop.
I think my major problem is the cold mornings and absolutely not enough time for warming up of the car.
With the CPS I am leaning towards a bad/old battery so far.
I will still have to check it out though.
I think my major problem is the cold mornings and absolutely not enough time for warming up of the car.
With the CPS I am leaning towards a bad/old battery so far.
I will still have to check it out though.
11-19-2008, 12:42 PM
#56
Senior Member
iTrader: (7)
Join Date: Dec 2004
Location: Alexandria, VA, & Central Jersey
Posts: 2,647
i'm not sure which parts you are not getting what i'm saying. Reason why i say that you should check with a scanner is because since you drive such small trips, you do'nt know when your ecu has determined that all of your system is ready. If you have a CEL, you reset it, try to get inspection, you can't because your ecu is not ready. A scanner will tell you if the system is ready and which systems are not ready. I.E., a bad 02 sensor might not come up right after you reset the ecu because it takes time for the ecu to sense that teh monitors are ready.
The guy who you called a newb comment was probably talking about how you keep resetting your ecu after you check your codes. Everytime you reset your ecu, you're not letting enough time in between for the ecu to do its job.
The guy who you called a newb comment was probably talking about how you keep resetting your ecu after you check your codes. Everytime you reset your ecu, you're not letting enough time in between for the ecu to do its job.
11-19-2008, 01:38 PM
#57
this now make a little more sense. Let me explain a few things now.
my every day driving is at least the short trips to school and work. I also go longer distances couple of times a week.
I do not reset the ecu every time I get a code, and I know I am not supposed to. What I do is double check. In this case with the CPS code for example I reset the ecu and will check again to see if it comes back up. There have been many times that a code has come up because there was a split second (not literally) that something did not work up to spec.
A good example of that would be a KS. As you probably know a KS code may and does come up when you change gas stations, type of gas etc.
I have driven with my CEL on before and with multiple codes.
And what I am still confused is what exactly scanner are you talking about? OBDII scan?code reader tool to pull codes?
my every day driving is at least the short trips to school and work. I also go longer distances couple of times a week.
I do not reset the ecu every time I get a code, and I know I am not supposed to. What I do is double check. In this case with the CPS code for example I reset the ecu and will check again to see if it comes back up. There have been many times that a code has come up because there was a split second (not literally) that something did not work up to spec.
A good example of that would be a KS. As you probably know a KS code may and does come up when you change gas stations, type of gas etc.
I have driven with my CEL on before and with multiple codes.
And what I am still confused is what exactly scanner are you talking about? OBDII scan?code reader tool to pull codes?
11-20-2008, 08:38 PM
#59
Senior Member
iTrader: (7)
Join Date: Dec 2004
Location: Alexandria, VA, & Central Jersey
Posts: 2,647
yes, a scanner, obd2 scan code reader for you to get codes. A KS code might not light up the cel light. It might be a ghost code. You might check for codes and see that there is nothing there. It might not be there because the system is not ready. I usually won't tell people to do this because you are correct that you can check the code yourself with a screwdriver. However, it seems that you are in a special case where you need to make sure that all your systems are up to par and are running. Or, your car just hates you and likes to eat gas
11-20-2008, 09:15 PM
#60
yes, a scanner, obd2 scan code reader for you to get codes. A KS code might not light up the cel light. It might be a ghost code. You might check for codes and see that there is nothing there. It might not be there because the system is not ready. I usually won't tell people to do this because you are correct that you can check the code yourself with a screwdriver. However, it seems that you are in a special case where you need to make sure that all your systems are up to par and are running. Or, your car just hates you and likes to eat gas
My car loves me, and I love 'er back even more. We have a great relationship going. So far this week I have been trying VERY hard to stay off the gas pedal and with a couple of longer drives than my regular once I have gone 100 miles and the tank shows to have gone down about a third.
I believe it's the cold and my lead foot in the morning being late all the time
11-21-2008, 02:27 PM
#62
Member
Join Date: Aug 2008
Posts: 81
That's a known fact based on the differences in the deflagration of the two types of fuel. But, ask anyone here, and they'll tell you that spending about two dollars more to fill your tank is better than spending a couple grand to replace/rebuild your engine.
Every single MPG thread ends up the same way...
Every single MPG thread ends up the same way...
11-21-2008, 10:54 PM
#64
Hey man, why dont you give me a quick run down of everything you have done and checked and know is okay at this point, casue through all of this theres alot of confusion and i dont know where to start anymore, ha.
i also wanted to point out that in my previous post that i said my 02 Sensor on the Upstream B2S1 was bad, i was wrong. i recently had my alternator go out and i replaced the ALt, my battery (under warrenty from NAPA) and i regrounded everything added a few new grounds and repplaced all my wires. My 02 code went bye bye.. so mabey it was a ground prblem, and since then the car has been responsive as all get out, as well as my fuel eco. increasing. so just some food for thought, if your grounds havent been taken care of in the last 200,000 miles you might wanna get to looking in that direction, haha
.
also, i can sympathize with you, i am a college student and i hate getting up early... but i try to start the car at least 5 mins ahead of time in the morning, rather than running her in 2nd gear til she warms up haha. but why not try doing that for a week and see if theres a Signifigant Increase or if were looking in the wrong direction.
i also wanted to point out that in my previous post that i said my 02 Sensor on the Upstream B2S1 was bad, i was wrong. i recently had my alternator go out and i replaced the ALt, my battery (under warrenty from NAPA) and i regrounded everything added a few new grounds and repplaced all my wires. My 02 code went bye bye.. so mabey it was a ground prblem, and since then the car has been responsive as all get out, as well as my fuel eco. increasing. so just some food for thought, if your grounds havent been taken care of in the last 200,000 miles you might wanna get to looking in that direction, haha
.also, i can sympathize with you, i am a college student and i hate getting up early... but i try to start the car at least 5 mins ahead of time in the morning, rather than running her in 2nd gear til she warms up haha. but why not try doing that for a week and see if theres a Signifigant Increase or if were looking in the wrong direction.
Last edited by FallenOne; 11-21-2008 at 10:56 PM.
11-22-2008, 09:58 AM
#65
just filled up for the week and I'm showing about 15mpg this time. I had a longer trip or two though so that means that I am still getting poor mileage.
I aint got a driveway so when I start the car I have to be in it the whole time and that is what I hate. back home I would run out first thing in the morning before I do anything and start the car. By the time I got out she was all warm
I have done some grounding work. I cleaned some of the grounds, added one to the starter when I changed it etc.
I aint got a driveway so when I start the car I have to be in it the whole time and that is what I hate. back home I would run out first thing in the morning before I do anything and start the car. By the time I got out she was all warm
I have done some grounding work. I cleaned some of the grounds, added one to the starter when I changed it etc.
11-22-2008, 10:30 AM
#66
Senior Member
iTrader: (7)
Join Date: Dec 2004
Location: Alexandria, VA, & Central Jersey
Posts: 2,647
get a remote starter. Problem solved. As far as getting bad gas mileage, i figured i wanted to rub it in your face since i got 27 mpg yesterday driving from Nova to virginia beach. And i think i got around 28-30 on the drive home. Got about 170 miles on the trip odometer and it hasn't hit the 3/4 line yet.
11-22-2008, 06:12 PM
#68
Senior Member
iTrader: (7)
Join Date: Dec 2004
Location: Alexandria, VA, & Central Jersey
Posts: 2,647
wth??!!!!?!!! then it means your car doesn't have any problems!!!!!!!! if you can get 29mph doing 80 on cruise control means your car is fine!!!! when you get the 12-13 miles is cause ur driving like you're a nascar driver!!!! don't floor it and you're good to go!
11-23-2008, 03:30 PM
#69
I don't floor her more than 2-3 times a week for few seconds to get out of some situations caused by idiots on the road.
I try to keep it below 3000 rpm with what ever I do. once you break 3k I know it gets way thirsty.
My tail pipe color has changed BTW. I think it looks lighter like white-ish color.
Does that mean anything?
If I check the plugs what am I gonna look for to tell if it runs rich?
Thanks!
I try to keep it below 3000 rpm with what ever I do. once you break 3k I know it gets way thirsty.
My tail pipe color has changed BTW. I think it looks lighter like white-ish color.
Does that mean anything?
If I check the plugs what am I gonna look for to tell if it runs rich?
Thanks!
11-23-2008, 04:42 PM
#70
Senior Member
iTrader: (7)
Join Date: Dec 2004
Location: Alexandria, VA, & Central Jersey
Posts: 2,647
black/burnt exhaust = running rich
White = running lean.
here you go
http://www.dansmc.com/Spark_Plugs/Sp...s_catalog.html
Also, running lean usually means power loss, not horrible gas mileage...so i'm not sure what the hell is wrong with your car now
White = running lean.
here you go
http://www.dansmc.com/Spark_Plugs/Sp...s_catalog.html
Also, running lean usually means power loss, not horrible gas mileage...so i'm not sure what the hell is wrong with your car now
Last edited by ImmaSquashYou; 11-23-2008 at 04:45 PM.
11-23-2008, 04:52 PM
#71
the KS is all good. no leak as of today. I will drive like that anyway but I was just trying to get some info in.
I had a thread some time ago about the ECU swap and I had questions about the EVAP system. No one gave me any answers. I feel that there could be a problem with that since I swapped the ECU and half of the EVAP stuff is still on the car even thought the computer does not recognize it.
I drive 3 miles to school and back, and the same with work. I know city driving sucks but 12 MPG?
I had a thread some time ago about the ECU swap and I had questions about the EVAP system. No one gave me any answers. I feel that there could be a problem with that since I swapped the ECU and half of the EVAP stuff is still on the car even thought the computer does not recognize it.
I drive 3 miles to school and back, and the same with work. I know city driving sucks but 12 MPG?
11-23-2008, 04:57 PM
#72
black/burnt exhaust = running rich
White = running lean.
here you go
http://www.dansmc.com/Spark_Plugs/Sp...s_catalog.html
Also, running lean usually means power loss, not horrible gas mileage...so i'm not sure what the hell is wrong with your car now
White = running lean.
here you go
http://www.dansmc.com/Spark_Plugs/Sp...s_catalog.html
Also, running lean usually means power loss, not horrible gas mileage...so i'm not sure what the hell is wrong with your car now
I'll just drive it and that's it. gas is cheaper these days anyways
11-24-2008, 12:30 PM
#75
^ if you can get 28 mpg at 80 mph... don't even worry about looking at your brakes.
I recently was getting 17-19 mpg highway and being a grandma in the city. I took my rear caliper apart since it was randomly screeching while off of the brakes. My last full highway trip was 26 mpg at about 75-80. And i have some major problems such as leaking/burning oil and a blown headgasket.
So you're right: you would know if your caliper was sticking at all.
I recently was getting 17-19 mpg highway and being a grandma in the city. I took my rear caliper apart since it was randomly screeching while off of the brakes. My last full highway trip was 26 mpg at about 75-80. And i have some major problems such as leaking/burning oil and a blown headgasket.
So you're right: you would know if your caliper was sticking at all.
11-24-2008, 01:06 PM
#76
Junior Member
Join Date: Jan 2008
Location: Chicago, IL
Posts: 23
They may not be hanging up that bad. I find the rear brakes are not that great anyway...VQ power > weak rear brakes.
Since you've gotten outstanding mileage in the summer on the highway, it would be interesting to know how it does now that the weather is colder. If you get reasonably close to high 20's, then I'd say it's mostly weather/driving style. If it's much worse (17-19 as mentioned by AndrewR2442), then it's more likely something with the brakes.
Since you've gotten outstanding mileage in the summer on the highway, it would be interesting to know how it does now that the weather is colder. If you get reasonably close to high 20's, then I'd say it's mostly weather/driving style. If it's much worse (17-19 as mentioned by AndrewR2442), then it's more likely something with the brakes.
11-24-2008, 09:09 PM
#77
as I said, I am going on a little trip on Wednesday and we will see what happens.
I got a drivers seat off of a I30 today and its so nice. I'm getting the other one (passenger) tomorrow
I got a drivers seat off of a I30 today and its so nice. I'm getting the other one (passenger) tomorrow
11-25-2008, 02:54 PM
#78
could an oil change give me bog difference with MPG?
I changed my oil on Saturday. This week so far I have gone about 60 miles and the tank is showing only 1/8 down. I use MaxLife blend 5w-30 if that matters.
I changed my oil on Saturday. This week so far I have gone about 60 miles and the tank is showing only 1/8 down. I use MaxLife blend 5w-30 if that matters.
11-25-2008, 04:17 PM
#79
it could, but it shouldn't affect it that much unless you had the wrong oil and were past due on the oil change
11-25-2008, 08:43 PM
#80
same oil as I have used since i got the car. I had yellow penz in it when I ran the Auto-RX treatment. other than that MaxLife every time. I never go more that 3500 miles on a change.