werid behaving BA hatch

[skitz]

hey guys got a werid one for u all lol

i got a 1.8L astina and tonight i was kinda playing with my car on the highway (first off i will say this isnt somthink i do all the time it is VERY occasional)

anyway in the merge to 100 i flatend it! 1st 4.5k, 2nd 6k, 3rd 6k and then at 5k in 4th is where it happened it was kinda like hiting the rev limiter but stickyer(if that makes any sence)(normal rev limiter is 7.250k)

i at first thought fuel and yes my light was on! but it usually would of has another 50km at least in her if i wanted to push it for kms before i would start worrying about fuel!

so i slowed down and tryed 3rd to see if it would do it again in a differant gear and yes it did at 5k i was like hmmm at this stage and when i was on the home straight to the peteral station i tryed 2nd and felt it at 4k, i thought this was werid as i was able to take 2nd and 3rd to 6k before and now couldnt

so i filled up and after trying to get as much fuel in as possiable i could only get 50.34L in but our tank is SUPOSEDLY a 55L tank so that kinda rules out the fuel prob (duesnt it?)i thought

so i went and tryed again and no probs in 2nd, 3rd at 5k and i left it at that not wanting to speed anymore!

anyone had this happen or know what it is ????

just for the record i wouldnt of kept going at this pass i was trying to see the top speed of 4th as i am still a relitivly new astina owner i havent pushed all its limits and i wouldnt normally go around doing this kinda stuff on the roads ESPECIALLY when other cars are around!

any comments welcome(go easy on any speeding coments plz lol)

thanks in advance
ps this would have to be my largest post lol

[platypus]

define "stickier"

the only thing i can think is that you were able to get better airflow and this is what created the difference

[skitz]

Originally Posted by platypus

define "stickier"

the only thing i can think is that you were able to get better airflow and this is what created the difference

um with the limiter it will bounce and the accelerator feels the same as normal but this made the accelerator feel sticky and the revs wernt stable as in i could keep pushing and it would kinda go up a bit then drop back down a bit etc till i backed off or went up a gear(if that helps at all it is kinda hard to explain)

ow and as for the airflow thing what u mean (i was going like pritty fast on an open road so it would of been getting good airflow)

[project.r.racing]

rev limiter is higher than 7250rpm.

fuel staveation simple...

you were running on fumes mate, air pockets in fuel line, prolly the reason why you couldn't feed more fuel in at 5000rpm when the vrs kicked in. and why revs going up n down. you were lucky you stopped when you did, i reckon you had 500m left in the gas tank.

even tho you have 3 litres left, the bottom of your tank is 40x80cm or so. that would mean you had 1mm of fuel in the bottom of your tank... think your in-tank pump works getting fuild out when it's 1mm deep? i don't think so.

why you running the tank that low? trying to suck all the **** at the bottom of your tank into your filter and injectors?

ryan

[chicaboo]

Originally Posted by deejayryry

why you running the tank that low? trying to suck all the **** at the bottom of your tank into your filter and injectors?

Since the fuel is already taken from the bottom of the tank, this would be just a common fallacy yes? Assuming the "****" at bottom of the tank is heavier than the fuel itself?

[skitz]

i was trying to see if i could get it close to 55L lol every time i fill up it is never more than 50L like usually 45ish so i guss thats why i cant use that last 5L lol and that would be why my fuel light comes on at 42ishL lol

also i traveled a good 40kms after the first 2 instences before i tryed 2nd on the home strech lol

thanks heaps guys for this

ps would it have been bad for the car at all? like the pumps etc?

[George]

hi, something else, what top speeds do you guys get out of these cars? for interest sake..

[boostedbatman]

I cant believe you would be upset by perfomance on an empty tank
Seeing that it fixed itself when you put fuel in .....??
Doesnt that answer everything for you

TOP SPEED
Use the search function and you will see

For now
http://www.astinagt.com/forums/showthread.php?t=7175

[skitz]

i aint upset just wanted to know if that was what it was or if it was somthink eles

[Rupewrecht]

You'll never get 55L into the tank. Fuel expands when it gets hotter, and there's always got to be room for it to expand.

[mill_mobile]

Jeez mate, call me a pansy, but i RARELY EVER rev mine past 4k-4.5K!!

[Dogo]

PANSY !! :P

THe pump doesnt exactly pick the fuel up from the bottom of the tank. It feeds from a small plastic tub which sits at the bottom - so its very possible that it could miss some.

But you never want to let the fuel get that low because the bottom of the tank is dirtier.

[skippy]

Also depend on rapid car movements and hills,

Basically fuel in a tank will follow gravity and interia,
If the fuel drains away from the pump feed it will bring in an air bubble,
This is unless we have surge tanks (i think they are called) which is like a second tank that is used to reduce the problems described above ie it is a small tank that is full at all times which the pump drain fuel from to take to the engine,

Personally I would only worry once youi start getting these sort of problems once you have a decent amount of fuel,

FYI I always fill up at about 1/3, anyway driving till you almost out means you can not get your petty on the cheap days unless you fluke it,

With petrol prices varying upto 20% during one week, saving upto 20% by doing something which is definetly equal or better for your car is a no brainer IMHO.

[KittyKatSmack]

For some reason, I thought the fuel tank was only 45L not 55L...

I try not to run the tank that empty, so I am curious as to why you are doing that.

I have had to replace the small white plastic fuel filter before because it got clogged.

I guess I treat my cars pretty well, never letting the tank run that low, and generally change gears around 4-4.5 too although the MX5 is built for higher revving - it's an itty bitty race car

skitz: we have to talk about treating your car nicer, especially if you want it to last.
Also, it's fine to enjoy driving your car, heck we all do, but I couldn't help but feeling that some of the things you said were pretty irresponsible.
I know, I know, my driving is pretty irresponsible a lot of the time too, but do as I say not as I do LOL!

Just look after your car a bit nicer ok? Treat her nice and she'll treat you nice etc.

See you Saturday

[skitz]

Originally Posted by mill_mobile

Jeez mate, call me a pansy, but i RARELY EVER rev mine past 4k-4.5K!!

hey man my normal driving is like 3 or sum times even lower!!

as i said this isnt somthink i do all the time and i wouldnt consider doing all the time

[Laser the Amazer]

when I had the Lynx in it got low I couldn't boost hard because of a lack of fuel pressure

solution: don't run really low and don't boost hard when low

Rob

[Aaron]

Well... I gotta say I thought the tanks were meant to be about 48 or 50L *shrugs* Either way to put whats happening into a nutshell.

1) Fuel is moving around the tank like it always does, becuase the Astinas use a system with a return there's also fuel coming back into the tank from the rail. So you have fuel sloshing about, it's pretty churned up and is probably quite bubbly as well. This means you density is down. Hence a lean out condition which the ECU tries to correct by cutting timing and dumping in more fuel. The fuel pressure goes all over the place becuase the compresses differently as well. All in all it's a pretty crap time to be trying to run a motor. This is why true race cars use foam filled fuel cells.

2) Your fuel pump is mounted inside the tank, and uses the fuel for cooling. So it's also heating up. This is OK while it's still getting fuel up the guts of it, but the fuel is also heating up in the tank. No the pumps not going to die becuase you run the tank to empty (low fuel warning) every time, but it may have a marginally shorter life. I've done about 300000km in EFI cars that I've owned since new and never had a fuel pump die. *shrugs* Although the pump in the Chrysler was a bit grumbly after 120000km

This crap ont he bottom of the tank story is due to die soon too I hope. Any car that's fairly modern will have a fairly flat tank, not so like older cars that had tanks mounted in all sorts of odd places that were deeper than long. Fuel is slooshing about in there constantly where you're driving and unless you've basically filled the car with dirt any grit and particales get sloshed into "suspension" in the fuel whiel driving. They will settle out when parked, but generally they're always being moved and picked up on the screen filter ont eh end of the in-tank pump. The smaller ones clog up the filter up in the engine bay... Given the age of the BA's it's probably a worthwhile exercise replacing both filters before embarking on performance mods, turbo conversions or costly fault finding for surging etc etc.

Skitz, I reckon you're brave running around so low on fuel - but you may like walking more than I do but hey at least you're getting out there and trying stuff out, asking questions and most importantly learning from others and your own experiences. I think people giving you a hard time about running so low on fuel shoudl think about some of the things they're saying in a more analytical sense. (ie crap in bottom of tank)

Rob; Oddly there's no such problems now. It could have something to do with the chronic fuel pressure problems, the fuel leaks, the vacuum/boost leaks, the poor idle and ignition timing settings and the incorrectly positioned BOV that were hallmarks of the mechanical package through your period owning the car.

[Dogo]

I replaced the high-pressure fuel filter ( I cant remember how often it reccomends you replace it ) and it made the car run a lot smoother. Try that,

Its in the engine bay against the firewall, down from the throttle butterfly

[skitz]

Originally Posted by Dogo

I replaced the high-pressure fuel filter ( I cant remember how often it reccomends you replace it ) and it made the car run a lot smoother. Try that,

Its in the engine bay against the firewall, down from the throttle butterfly

wait is that sumthink i should do?

thanks heaps for the feed back guys and thanks aaron

[bourbon]

Originally Posted by skitz

wait is that sumthink i should do?

thanks heaps for the feed back guys and thanks aaron

i reckomend it kylie hahahaha not only makes the fuel cleaner goin through can give better fuel econemy.