Excessive fuel consumption

[fat tony]

I know I'm supposed to reach around 400 to the tank... I have a malpassi fuel pressure reg, and all runs quite
smoothly, but I reach around 200 kms to a full tank WTF?

 

[GROOV3]

when i first got my evo 2 it was just a 2lt with a large turbo and tune etc.

i was getting 150kms - 200 a tank

i took it to get looked at and the timing was WAY off. I think from memory the exhaust side.

either way this was corrected and my fuel rate went up to

300 odd kms a tank which was great compared to 150km


So maybe its a similar issue, maybe book a dyno run and get someone to have a look



now its back down to 250 ish but thats cause its a stroker and i drive it quite hard.

 

[CLuTZ]

whats your car and what mods do you have?

My old VR4 with GT30R and Autronic SM2 used to get 150kms MORE per tank than stock ECU and turbo.

What do you need an adjustable FPR for? Why not just get the correct sized injectors?

 

[Dean]

Way too excessive.
Get your ECU tuned and you'll be sweet after that.

 

[fat tony]

94 cc gsr, standard 1.8, standard turbo, only mods are higher boost, 14 psi, and malpassi fuel pressure reg, and 3 inch exhaust... bought it as is and i am unsure if it was tuned iregularly, timing is spot on, and ecu and all is stock, i recently had to change the crank sensor, and it occasionally will missfire at high revs, also when i accelerate it feels as though the boost is choking, or struggling to get thru if u know what i mean...

 

[EVO-00X]

Could also be your 02 sensor mate.
I'd ditch the Malpassi, its not needed for those mods therefore put a stocky back on.
Are you sure the timing is spot on? Have you earthed out the timing plug on the firewall and checked with a timing gun?
Also, any evidence of leaks in the intake pipe or intercooler pipes?

 

[Dean]

Checked your spark plugs?
As above, you might have a small vac leak somewhere which to compensate, the ECU is dumping more fuel in due to excess air coming in.
Take out you're plugs and if they are black then there's your evidence.

 

[fat tony]

no i changed the plugs about 2 months ago, no leaks as far as im aware and yes checked timing with a gun and all was earthed... the guy before me rekns it had magna injectors i dont believe him coz they looked the same as were in my mates old gsr.. maybe he wasnt lying? cos he also tried to tell me he had stage 2 cams in it and all was rebuilt but there was no receipts.....

 

[milkandoj]

Some of the malpassi regs rise at a rate of 1.7 :1. If it is one of these it will be messing with your afr's.
Not 1:1 like you stock reg will, or a sard will.

So the stock computer will be expecting the fuel pressure to rise at a rate of 1:1 psi according to the pressure in the manifold and if it rises at a 1.7 :1 rate you'll be running alot higher fuel pressure than expected by the ecu, so way more fuel will be going in.

The theres all the other stuff to look at, try searching for fuel economy ect on here.

Other things that may be contributing are the oxygen sensor not working or water temp sensor for the ecu.

 

[Liberoz]

sell the Malpassi and buy fuel with the $$ put the stock fuel reg back on and check all your IC piping joins & exhaust joins mani dump front pipe, if little improvement check your plugs!
also what ron fuel? & brand are you running in it?

 

[Dean]

While you're at it, buy these and piss off those magna injectors

http://cgi.ebay.com.au/390cc-gsr-la...ZAU_Car_Parts_Accessories?hash=item4a9c144831

 

[CLuTZ]

It amazes me why someone would change the injectors and FPR on a stockish GSR! No need, especially when you're swapping them out for smaller injectors! Aren't they 220cc? Spose it depends if they're 4 or 6cyl injectors. I'd be getting a stock FPR and injectors on her pronto. Change the plugs while you're there, to BP6ES.

 

[3zercrowd]

Change the plugs while you're there, to BP6ES.

Again Dre BKR6E for gsr's......

You keep quoting for Evos

http://4gtuner.com/site/showthread.php?t=4745

 

[Entaran]

O2 Sensor borked
Water temp sensor borked
Injectors wrong size
FPR borked
New plugs (will be required anyway, obviously running way rich and fouled them)
Timing

Worst case scenario, book some dyno time.

Top of my list would be your o2 sensor being stuffed and it never coming out of closed loop programming

 

[CLuTZ]

Again Dre BKR6E for gsr's......

You keep quoting for Evos

http://4gtuner.com/site/showthread.php?t=4745

lol sorry- but who would want an 1800 these days anyway?? :lol:

 

[Richard]

While your at it you better put a new set of spark plug leads and a walbro fuel pump to get rid of the missfire but do all the other stuff ^^they sugested.