ihatemybike
Explorer
Try the distributor swap yet?
Have you run it in the dark to check for arching?
Have you run it in the dark to check for arching?
Newbie AWD Astro Overlander Build
- Thread starter nobodyhome
- Start date
nobodyhome
Adventurer
Not yet, planning to swap the whole thing...thanks guys!
nobodyhome
Adventurer
Update:
VERY grateful for all the support, thanks everybody!
OK, so miscommunication at the shop.. Oscilloscope test has not been done yet, so we shall see what that yields.
So this project maybe slow going from here until I get the misfire licked since I cannot get it smoged/ registered with it throwing codes.
VERY grateful for all the support, thanks everybody!
OK, so miscommunication at the shop.. Oscilloscope test has not been done yet, so we shall see what that yields.
So this project maybe slow going from here until I get the misfire licked since I cannot get it smoged/ registered with it throwing codes.
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Mwilliamshs
Explorer
Evil Patrick makes a good point.
TireRack dot com says your stock size is 215/75-15 and Firestone Destination LE2 says 753 revs per mile in that size. 235/75-16 says 698 revs per mile in same tire. 698/753 = 92.69% as many revs per mile. With a 27 gal stock fuel tank (just googled it, might not be correct for your personal van) and EPA rating of 21 mpg highway, you'd go 567 miles on a tank and 426,951 tire revs. Same tank and assume no loss of fuel mileage your odometer would see only 395,766 tire revs and indicate that as only 525.5 miles.
On stock tires, you see 567 miles, divide by the 27 gallons it takes to fill up, and figure you're getting ~21 mpg. (EPA estimate)
On big tires, you see 525.5 miles, divide by the 27 gallons it takes to fill up, and figure you're getting ~19 mpg. This if you're still getting exactly the same mileage as before and have an accurate, unmodified odometer and it's actually about 19.46 so a loss of 1.5 or so. BTW, 19.46/21 = 92.6% again. It all checks out.
Stroverlander
Adventurer
Even with larger tires, 13 mpg is not good for an Astro AWD and something is still not right. Still haven't mentioned the gear ratio...
You can also forget about using EPA estimates, no one ever got 500+ miles out of a tank in one of these. For starters, only around 25 gallons of fuel in the 27 gallon tank can really be used before the fuel pump starves.
Also, I'm with Aaron, pull the distributor and check the gear for wear. Any of the cheap, all aluminum distributors are decent - Skip White Performance, WPS, United Ignition, etc.
You can also forget about using EPA estimates, no one ever got 500+ miles out of a tank in one of these. For starters, only around 25 gallons of fuel in the 27 gallon tank can really be used before the fuel pump starves.
Also, I'm with Aaron, pull the distributor and check the gear for wear. Any of the cheap, all aluminum distributors are decent - Skip White Performance, WPS, United Ignition, etc.
nobodyhome
Adventurer
Agreed, and yes a very good point. I have the same issue with my YJ, where the odo/ speedo are 10% slower than actual, so i calculate as follows: miles x 1.1 / total gal used.
Here's what I did on the van, please let me know if you think this works. I always fill to absolute top based on sound (vs pump click-off because that varies wildly), so shouldn't be much variation there. There is some margin of error between temp/ altitude, gas formulation/ ethanol content, driving style and GPS error rate, so obviously the more data points to average together, the better the data.
Before and after the new tires, I averaged my speedometer vs. GPS speed via the Torque ap. My speedo and OBDII agree within +/- .7MPH. After the tires were replaced, I took an average of OBD vs GPS differential readings and came up with a 6% difference between "actual" and measured speed. Taking into consideration this difference, I recalculated my economy as: miles x 1.06 / total gal used. With only 2 full tanks since the tire change, the average is weak due to lack of data points; 12.75mpg, down from 16.5 before the tire change= difference of -3.75 mpg. Factor in a tiny bit more city driving than the baseline, call it 3.
I was lucky in that the previous owner did not reset the overhead trip computer in a reeeeally long time, so according to that it got 16.6MPG average over 800+ gal used. My pump side calculations were 16.5, so I believe it. Is it perfect? NOPE! But close enough for non-government work.
I am really hoping that the tune up will help; the plugs were OOOOOLD! We should have results from the engine analyzer later this week. This is the fancy way of looking for sparks in the dark like I did every time I went camping in pitch dark, but it also measures the fuel pulse timing vs. spark vs... how many squares I used to wipe this morning, so... ummm everything I think. haha
OK, Stroverlander- I saw the van at the shop yesterday and COMPLETELY spaced on looking at the door sticker!
Based on my Jeep experience, I tend to believe that its very likely to have the lower gear ratio. The distributor is being replaced regardless of scope outcome. I doubt the P.O did it so it likely has the full 216K miles on it.
Great discussions, love it here!
Here's what I did on the van, please let me know if you think this works. I always fill to absolute top based on sound (vs pump click-off because that varies wildly), so shouldn't be much variation there. There is some margin of error between temp/ altitude, gas formulation/ ethanol content, driving style and GPS error rate, so obviously the more data points to average together, the better the data.
Before and after the new tires, I averaged my speedometer vs. GPS speed via the Torque ap. My speedo and OBDII agree within +/- .7MPH. After the tires were replaced, I took an average of OBD vs GPS differential readings and came up with a 6% difference between "actual" and measured speed. Taking into consideration this difference, I recalculated my economy as: miles x 1.06 / total gal used. With only 2 full tanks since the tire change, the average is weak due to lack of data points; 12.75mpg, down from 16.5 before the tire change= difference of -3.75 mpg. Factor in a tiny bit more city driving than the baseline, call it 3.
I was lucky in that the previous owner did not reset the overhead trip computer in a reeeeally long time, so according to that it got 16.6MPG average over 800+ gal used. My pump side calculations were 16.5, so I believe it. Is it perfect? NOPE! But close enough for non-government work.
I am really hoping that the tune up will help; the plugs were OOOOOLD! We should have results from the engine analyzer later this week. This is the fancy way of looking for sparks in the dark like I did every time I went camping in pitch dark, but it also measures the fuel pulse timing vs. spark vs... how many squares I used to wipe this morning, so... ummm everything I think. haha
OK, Stroverlander- I saw the van at the shop yesterday and COMPLETELY spaced on looking at the door sticker!
Based on my Jeep experience, I tend to believe that its very likely to have the lower gear ratio. The distributor is being replaced regardless of scope outcome. I doubt the P.O did it so it likely has the full 216K miles on it.
Great discussions, love it here!
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Stroverlander
Adventurer
Yeah, tough to tell gear ratio when it's in the shop. :Astrologist: Good luck and hope you get it back and running right soon.
ihatemybike
Explorer
Grumpy has come really close though, going 490.4 miles burning 25.792 gallons. Interstate driving usually it would avg 18-20 mpg, highest it ever returned was 28 mpg. I really need to put this van back on the road.
The 1999 2WD I recently sold often went over 500 miles.
Both these vans are from the 25 gallon tank years.
Gandalf, my current daily driver has a 20.05 mpg best tank so far, after I repair/replace the slightly crushed tank I should be able to surpass 500 miles.
I've been logging my gas mileage for years.
http://www.fuelly.com/driver/ihatemybike
ihatemybike
Explorer
These vans came with the following gears.
Common
2WD: GU5 3.23
AWD: GU6 3.42
Uncommon
AWD: GT4 3.73
The G80 limited slip rear differential was optional on the AWD vans and on the GT/RS 2WD vans. Checking junkyards around here it appears to be about one in eight AWDs with the G80.
Common
2WD: GU5 3.23
AWD: GU6 3.42
Uncommon
AWD: GT4 3.73
The G80 limited slip rear differential was optional on the AWD vans and on the GT/RS 2WD vans. Checking junkyards around here it appears to be about one in eight AWDs with the G80.
nobodyhome
Adventurer
No kidding Aaron, well it appears to me that here in SoCal, on a good day, only 1 out of every 60 or so vans is AWD. Therefore, if 1 in 8 AWD vans has a G80, then the chances of me finding one is what... 1:480? Might as well play lotto.
Ohh, here is something funny for our fellow Astro-Fans... check out what Urban Dictionary defines them as... HAHAHA.. http://www.urbandictionary.com/define.php?term=Astro+van&utm_source=search-action My first van everyone called the Creeper Van.
Ohh, here is something funny for our fellow Astro-Fans... check out what Urban Dictionary defines them as... HAHAHA.. http://www.urbandictionary.com/define.php?term=Astro+van&utm_source=search-action My first van everyone called the Creeper Van.
nobodyhome
Adventurer
So far, best from the Adventure Van was 16.6mpg on the drive home. Worst was 11.1mpg.... YUCK!:Wow1:
The best the Creeper Van ever ('99 2WD Safari) did was 20.7mpg. Greatest distance on one tank was 440 miles, probably could have got up to around 470 but didn't want to chance it or wipe out the new fuel filter.
I use an app called 'aCar' to track everything. It claims to talk to Fulley.com but I'm still trying to figure it out.
The best the Creeper Van ever ('99 2WD Safari) did was 20.7mpg. Greatest distance on one tank was 440 miles, probably could have got up to around 470 but didn't want to chance it or wipe out the new fuel filter.
I use an app called 'aCar' to track everything. It claims to talk to Fulley.com but I'm still trying to figure it out.
nobodyhome
Adventurer
So far, best from the Adventure Van was 16.6mpg on the drive home.
The best the Creeper Van ever ('99 2WD Safari) did was 20.7mpg. Greatest distance on one tank was 440 miles, probably could have got up to around 470 but didn't want to chance it.
I use an app called 'aCar' to track everything. It claims to talk to Fulley.com but I'm still trying to figure it out.
The best the Creeper Van ever ('99 2WD Safari) did was 20.7mpg. Greatest distance on one tank was 440 miles, probably could have got up to around 470 but didn't want to chance it.
I use an app called 'aCar' to track everything. It claims to talk to Fulley.com but I'm still trying to figure it out.
ihatemybike
Explorer
The best mod I've found to improve gas mileage is to adjust the occupier of the driver's seat via increased data input.
ScanGaugeII
UltraGauge
Torque App for Android
ScanGaugeII
UltraGauge
Torque App for Android