What to check to reduce MPG?

2lude · Post by **2lude** » Wed Apr 11, 2012 3:35 pm

Always helped me my pos I'm driving now was doing really bad mpg and its a 1250 cc after a few red x doses its a lot better

Post by **paul bristol uk** » Wed Apr 11, 2012 4:34 pm

Have you done all on this check list?
http://www.preludeonline.com/f28/gettin ... de-238270/

BTW your subject should read "What to check to increase MPG?" you seem to be reducing it very nicely!

Also a long shot but perhaps your "flux capacitor" is on the blink?

Post by **Ammo** » Wed Apr 11, 2012 5:18 pm

Just done a compression test

These are left to right not in cylinder order

Now I did come across a problem, the middle 2 cylinders got to about 260ish needle would stop but if I crank more the pressure would drop back to 0. The other 2 the needle would just stop at it's highest point and go no further (About 250)

Dunno if that's my gauge or the engine?

littlefeller · Post by **littlefeller** » Wed Apr 11, 2012 5:42 pm

not sure i understand what you are saying here, if im understanding it correctly then seems your guage isnt working as it should, did you run the test again?. i have a brand new guage if you need to borrow one

Post by **Ammo** » Wed Apr 11, 2012 5:55 pm

Yeah Just ran the test again (But with the engine up to operating temp as had to charge the battery) and didn't get the drop off, must have been my tool not sealing properly

Left to right again

270psi

276psi

272psi

265psi

These numbers seem a little high to me? isn't it normally around the 250 mark?

Am i doing the test right? I've disconnected the Dizzy but not the fuel

littlefeller · Post by **littlefeller** » Wed Apr 11, 2012 6:01 pm

the test is fine, its a jdm so it will be higher. you may have to try 2ludes idea of reseting the ecu, though i would have thought it would run very lumpy if it were that rich, and if you had a leak somewhere it would really stink, has someone stolen your fuel

BMCC · Post by **BMCC** » Wed Apr 11, 2012 7:21 pm

I disabled the ignition and fuel systems when I checked the compression on my civic. It was also up to temp. I just followed the Haynes manual! Would the fuel in the cylinders explain your higher than expected readings (if this is what they are as I have no idea what they should be!)

Post by **paul bristol uk** » Wed Apr 11, 2012 7:47 pm

Ammo wrote: must have been my tool not sealing properly

Sorry Tom!

bmcc might have a point about the fuel in the Cylinder though.

littlefeller · Post by **littlefeller** » Wed Apr 11, 2012 8:00 pm

the fuel will only effect volume, as this is a pressure test it wont make any difference, people were doing compression tests when thay had carbs. the compression doest appear to be the problem though

vti2003 · Post by **vti2003** » Wed Apr 11, 2012 8:18 pm

Bit of a random one here but I eventually tracked a similar problem along with a very slight hesitation to the TPS on mine.

I was getting 200ish to the tank when I got the car. After working my way through everything else I unplugged it for a couple of weeks and was getting about 230ish to a tank.

After replacing it I now get 260ish to a tank.

The general opinion at the time was that unplugging the TPS would ruin fuel economy. I got the opposite effect from it. I suspect the tps was worn/dirty in the range where it sits while just cruising along.

It's free to try it so might be worth a go?

Lude Generation

What to check to reduce MPG?

Re: What to check to reduce MPG?

Re: What to check to reduce MPG?