hi guys i currently own a s4 rx7 13bt
at the moment unde the bonnet is a
13bt
mild port, magnacore leads 10mm and running a microtech mtx8 the rest is all stock as a rock.

my problem is that iam getting terrrible fuel consumption...
bad as in 110-120kms/ tank...

just wondering if anyone could enlighten me on my prob as no one else has been able to put their finger on it .sorta.

ive had my compression checked, it read 75 70 30
80 75 80
i know that means it prety much a side seal?
but i have no problems with power nor start ups cold or hot

it smells reallllly rich but i just got it tuned about 2months ago...

any help would be greatlly appreciated.

andrew.

 

That compression isn't much to cheer about...

We have a "mileage" thread about once a week, do a quick search and you'll find plenty...

 

wth? 120 k to a tank!!!!?!?!?

thanks.... *puts thinking hat on*

1.25 miles per litre... which is like FIVE mpg... wow. and I thought MINE was bad.

 

try a new O2 sensor. if you guys have them there? <-stupid

 

does the exhaust ever have blackish smoke? actually, it just sounds like the gas is leaking out, park your car over cardboard and see if you can find a leak,.

 

sound more like an agressive port than a mild one, if the milage is that poor, and your compression is way under spec. 80-85 PSI is the absolute minimum (and I actually think that the motor should be rebuilt if compression is less than 90 psi warm).

 

how do you get 75 70 30 all in the same rotor??? anyways, sounds like a fuel leak, check injector orings. Pull UIM and turn the fuel pump on and inspect for leaks.

 

Man that's worse than my Jeep, and I thought that IT sucked.

 

its not called economy when its that bad



(ok i'll go back to the FB section now)

 

I figured it was a typo and probably 75-70-70,

but it is too low either way

 

yeh i though the compression was abit strange but thats what the mechanic told me and thats what on the papers :/
so yeh it aint a typo...
it 30 in one chamber really odd?

pretty certain there isnt a leak anywhere at the back of the car.
yepppp plentyy of blackish smoke

o2 removed i think? im running a microtech

 

Go ask the mechanic to recheck. With numbers that low, that almost sounds like something bad is coming down the road, or has already hit and is waiting to make things worse.

 

Did somebody tune for 460s and forget about some 1600cc primaries or something?

I'm inclined to think it's not properly tuned. Lots of dark smoke isn't a sign of a good tuning job.

-=Russ=-

 

one bad
maybe one sideseal is gone
or both??

 

Has the Microtech been tuned at all? The base map is stupidly rich. I'm surprised you're even getting 120K if you're using that map...

Edit...I just read that it was tuned. What are your A/F ratios? Either there is something horribly wrong (poor tune) or a mechanical failure (bad injector, fuel leak, etc.)

 

I still dont get how you get 30 in one side, when the rest are 70

 

okies guys had a mate look at things and we came up with the conclusion that most of the hardware is in pretty good nick inc. motor.

anyhow got him to look at a few things on the tune and turns out i had 25 deg btdc on idle which he found real perculiar, CAS was locked so couldnt adjust, got that sorted and now have idle at 2 deg btdc

took it for a drive and he took out about 20% fuel and now its heapps better but thats just the cruise maps.

havnt been able to tune the boost maps because we dont have an uego sensor
so ill have to take it to a TRUSTED and GOOD tuner to redo the boost maps AGAIN!!!
i cannot believe this is happening because the first time round i got things tuned it was by a reputable workshop!!! one of the BEST! oh well....

nowadays its still fouling the plugs abit but will have to get it all sorted out later this week.

i still dont understand why my comp readings were funny!?
what seems to be so strange?
and yes im SURE that the mech assured those readings.
he based him judgement that it was missing a beat at first but we fixed that up in the tune today and she running heaps nicer.

 

guys could someone please explain to me why my compression readings are soo odd?
i dont see the strange side to it :/

 

Just a warning, I ran a Wolf3D with a very rich set of cruising maps (low rpm and low loads)for a couple of months. The result was a hollowed out Cat (basically cooked it), which would have been okay if I hadn't just purchased it. My fuel economy was just over 200km a tank, and when you drove it hard it made no difference. A trip to the dyno to get cruising milage sorted got me back to 350kms for city and 450+ for highway (the top end maps were fine).

 

hmm thanks. but im sure my cat died monthssss ago. i dont care =p