4agte fuel consumption bad after Link tune.

[~SlideWays~]

My 4agte has always used a shed load of fuel. It managed about 250k per tank with the gze afm ecu.

I've upgraded to a LinkPlus and had it professionally tuned with a high boost setting of only 13psi.

I've now used 3/4 of a tank and its only managed 200k's!! I have indeed trashed it but this still seems wrong?

Could there be a problem with the injectors or something else?

I did notice last time I took the injectors out, that the squirter end of one of them was loose enough for me to turn it with my fingers. Could this mean fuel leaking through or anything?


Any help would be appreciated...by my fuel bill!

[Crucible]

If the fuel pressure is the same as it was prior to the tune, and its still on factory injectors then its probley using more gas because of the tune, he may of just done a safe tune which runs a little richer throughout boost to be on the safe side. Most injectors can turn quite easily in the rail, if they arent leaking then its probley not the problem. Differant ign timing, more boost, and a totally differant fuel map etc can all contribute to poorer fuel consumption.

[~SlideWays~]

Im not talking about the end which is in the fuel rail, its the other end where the fuel actually is sprayed from. This is the part which turns but none of the other do.

Yeah it is a completely different MAP ect, but people are getting better fuel consumption with 4agte's and making much more power and using more psi.

Thats what made me think there might be something else causing the problem.

It was tuned by a well known place too.

It is using just as much as it did with the old ecu as well which is too much of a coincidence!

[mikeygtt]

When i owned a gtx mazda i use to only get 250k out of the tank. It was modified quite a bit too. sounds normal.

How hard have you been driving it since the linkplus was set up:twisted:

[Bazda]

yea thats crap fuel consumption.
My new car does way better than that lol
its like 350km per tank, But i do got a good ecu

All my mates with links seem to run real rich down low revs, i duno why but also been tuned by a good tuner, seems to be the only way to make them go properly or something....not enough map point....

[4000GT]

My 4agte has always used a shed load of fuel. It managed about 250k per tank with the gze afm ecu.

I've upgraded to a LinkPlus and had it professionally tuned with a high boost setting of only 13psi.

I've now used 3/4 of a tank and its only managed 200k's!! I have indeed trashed it but this still seems wrong?

Could there be a problem with the injectors or something else?

I did notice last time I took the injectors out, that the squirter end of one of them was loose enough for me to turn it with my fingers. Could this mean fuel leaking through or anything?


Any help would be appreciated...by my fuel bill!

So you improved your fuel economy by adding the Link... If you thrash your car, its not wonder you use lots of petrol, especially if on boost a lot. If your AF's are right and your not leaking fuel, welcome to higher boost modified cars.

[QikStarlie]

dyno tuned? and exhaust probe? at low exhaust flow (low revs) exhaust probes can give the wrong afr (lean) by quite alot. due to revision. so they put too much fuel in.
dyno could be putting too much drag on engine for them to tune low vacume maps as well..

my car uses bugger all fuel with linkplus. just takes alot longer to get off boost part of themap right than wot part.

nothing to do with the ecu itself, tune it better

[Jason T]

Im not talking about the end which is in the fuel rail, its the other end where the fuel actually is sprayed from. This is the part which turns but none of the other do.

Thats called a pintle cap if you can turn it it will cause a vacum leak past the rubber seal causing slight rough idle and a boost leak replace all the caps and rubber seal to the head

Check your PMS sending link of were to buy replacments

[/url]

[johntramp]

you used to get 250k per tank, and now you are getting 200k per 3/4 tank (while thrashing it)... ie 266k per tank => better fuel economy.
What are you winging about?

[evil_si]

it is a bit excessive, how big is your tank?
the cap on the injector isnt supposed to be loose. what injectors are you running? may be an idea to swap them to try and determine the fault.

and also how was it tuned? dyno, road? was a wide band used? was it a decent tuner?
ive had plenty of turbo cars with link's and havent had fuel consumption that bad.

[~SlideWays~]

it is a bit excessive, how big is your tank?
the cap on the injector isnt supposed to be loose. what injectors are you running? may be an idea to swap them to try and determine the fault.

and also how was it tuned? dyno, road? was a wide band used? was it a decent tuner?
ive had plenty of turbo cars with link's and havent had fuel consumption that bad.

Im using the std 365cc gze injectors and std ae92 tank about 45L. It was tuned by speedtech down here in wgtn. Both dyno and road tune but it was pissing down with rain so wasn't much of a road tune.

I would like to swap the injectors, and could take the ones out of my later model gze maybe.

What is the story with swapping to different injectors though? ie if I used some bigger ones from an evo or supra... I know they will make it even worse but will it need to be tuned again if nothing else is changed?

johntramp: is that supposed to be funny?

Jason T: thanks mate, very helpful!

QikStarlie: yep on a dyno but he used a temporary o2 sensor, now there is just a bung

Bazda: Yeah, if think the better ecu with more map point would make a big difference. But the thing for me is that others have used the same ecu and similar setups to mine and have better economy. Also I am only running a high boost setting of 13psi and low of 7psi.

[Crucible]

What is the story with swapping to different injectors though? ie if I used some bigger ones from an evo or supra... I know they will make it even worse but will it need to be tuned again if nothing else is changed?

Yeah will need to be retuned cause the inj pintle/ orifice is larger, So if you were to just fit them now it would run way rich because the pulse width would be set at the correct a'f ratio for the 365's. 440's etc will flow more fuel per pulse than the 365's. Run it for a few days and wip out your plugs to check the colouring, if they are slightley blackish in colour is a good sign that its rich and may need to be retuned, you can tell a lot from plug colouring.

[EVLGTZ]

Sounds a bit excessive but may just be due to your right foot getting a workout since the tune.

My 4agte with link and 18psi use to get 400km tank easy, sometimes 450 open road, unless i was really stropping it around town and then it maybe 350km at worst.

Thats with upgraded fuel pump and 440cc injvectors too.

Oh yeah I'd call my tune pretty safe as well.

[Akane]

That's crappy
did they do a off-boost tune as well?
some tuners only tune for peak power.

[Crucible]

What would be the largest size injectors you could use on a 4agte before they would have problems getting the fuel right by pulse width. Would say 550s be too big for adjustment for example? and would 440,s be ample for say a little over 200kw atw (just for example)

sorry dude dont want to hijack your thread!

[evil_si]

since you have another set of gze injectors available do a swap, see if the problem follows,

speed tech have a very good name so would have thought it'd be spot on, have you spoken to andre about the fuel consumption problem? what did he say?

ok a couple more questions for ya.
what fuel pressure are you running?
what fuel pump? standard? aftermarket?
what fuel reg, standard? rising rate?


edyn ive had good results with 440cc injectors, i think bazda using 510's?

[4000GT]

Link do a better ECU, the G2. It has user definable map points, but people are usually to cheap to go for the extra functions.

[evil_si]

if tuned properly a basic link is fine,

sure link plus and the g2 have more features, but if you dont need them why shell out all that extra $$ for f all.

[4000GT]

if tuned properly a basic link is fine,

sure link plus and the g2 have more features, but if you dont need them why shell out all that extra $$ for f all.

Its not F-all though, its a LOT more... I agree if you dont need the functions then fine, and for my track car the LEM V5 is fine, but if you want factory like drivability you need the G2.

[IH8TEC]

bazz has 800cc injectors, i think i found why i was getting alot of kms with mine slideways, too lean lol, will let you know when car is going and after dyno.