[Mk2] [Turbo] turned my boost up and i think i hit fuel cut??

[hagghill]

i went out for a play earlier tonight and ive gradually been tweeking my ebc up in very small increments, its been set to 0.8 bar which i found impressive performance wise i have to say.

i turned the dial a little more earlier and anything upto 1bar was fine and the car really flew but any higher and the yellow/orange light popped on for a second on the dash and it was asif the ignition had been turned off for a split second and lost power (almost like fuel cut) is this the ecu stopping the car from melting?

i turned it back down and its running around 0.95-1bar with no problems now and at this boost there is a noticable difference over the 0.8 bar its been running

the thing is ive been told that its possible to run 1.1-1.2bar without any problems on a rev 3? any ideas as to why this has happened?

my engine spec is as follows...

Apexi gt cat back exhaust,
ARC trapped cold air filter system,
Apexi power fc with commander,
Blitz variable boost controller,

the car still has standard downpipe with cat, standard grade spark plugs and stock i/c.....could these standard items be the reason this happened earlier tonight?

thanks

[Steve-O 2007]

most likely need a fuel cut defender, only £14 or something

oh and get rid of the Cat

[L0rdMike]

most likely need a fuel cut defender, only £14 or something

oh and get rid of the Cat

You dont need one on a Rev3.

[lukem]

there's loads of previous information on this if you search. it will have been fuel cut (1.3 bar-ish? on rev3).

the common consensus seems to be that with your set up you should run around 1.0 bar max.

with any increased boost levels you should ensure ignition components are in good condition & use a colder grade of plug.

you should use an uprated intercooler run 1.0 bar+.

and get rid of the cat. not required on your car for the mot

[Mikey P MR2]

Your rev3 should not be hitting fuel cut at 1.1 or 1.2 bar. (i think 1.1 will be ok on a standard intercooler as i ran like this for ages without problems). maybe you boost gauge is alittle out?

[2Crooky]

I suspect ignition components rather than fuel cut........

Unless it spiked to 1.3 bar without you realising....What does the peak boost figure read as for your last run????

When were your sparkies last changed along with rotor arm, dissy cap etc????? When i fitted my Nur Spec to my old rev 3 my boost climbed to 1.1bar and the power started to cut out at 4.5k rpm.......I changed the spark plugs and hey presto, the problem was solved.

If you are running 1-1.1 bar you really should have a colder grade plug.

HTH

[jimGTS]

most likely need a fuel cut defender, only £14 or something

oh and get rid of the Cat

You dont need one on a Rev3.

especially one with a power fc, fuel cut could be 50psi if you wanted, lol


can you actually see the power FC fitted in the boot?

perhaps whoever mapped it set fuel cut at 1.1bar or something.


what is your commander telling you?? what knock levels? what temps?

[hagghill]

I suspect ignition components rather than fuel cut........

Unless it spiked to 1.3 bar without you realising....What does the peak boost figure read as for your last run????

When were your sparkies last changed along with rotor arm, dissy cap etc????? When i fitted my Nur Spec to my old rev 3 my boost climbed to 1.1bar and the power started to cut out at 4.5k rpm.......I changed the spark plugs and hey presto, the problem was solved.

If you are running 1-1.1 bar you really should have a colder grade plug.

HTH

Thats exaclty where mine cut out, i think i had turned the dial a bit too much on the boost controller and the car made 1.09bar according to the fc commander and it was at 4600rpm when the em light came on and the car fealt like it cut out

when i turned down the boost the fc commander showed a peak of 0.97bar which is 1bar as near as damn it and at this level the car was fine no problems at all

im not sure when the dizzy cap, rotor arm or plug leads where last changed but ive replaced the standard denso plugs with some ngk bkr7eix iridiums today.

although i havnt had the chance to get the car upto full boost yet im hoping this will cure the problem although im not really fussed about running more than 1bar anyway

[hagghill]

most likely need a fuel cut defender, only £14 or something

oh and get rid of the Cat

You dont need one on a Rev3.

especially one with a power fc, fuel cut could be 50psi if you wanted, lol


can you actually see the power FC fitted in the boot?

perhaps whoever mapped it set fuel cut at 1.1bar or something.


what is your commander telling you?? what knock levels? what temps?

yes ive seen the apexi ecu in the boot its behind the carpet, it is possible that whoever has mapped it has set the fuel cut at 1.1bar although i have no idea as it was mapped in japan

the commander didnt have the knock displayed until earlier today, it had water temp, air temp, boost and revs but ive removed the ari temp and now ive got knock showing instead.

the water temp stays around 82, the air temp was about 30 something last night and since displaying the knock its highest was about 30 at 0.84 bar

[hagghill]

by the way thanks for everyones comments

[Harry]

Mm caution!!!...Most likely If mapped In Japan It Is to their higher octane fuel and yes It Is possible that some one set It to 1 bar but what's the point? Sorry does not sound right. Personally I would have It tweaked and or remaped then you know It's spot on.For all we know some one could have just plugged the FC ECU in with some one elses map; from another MR 2? Unless you have all the dyno graph print out back ground data?

My OEM ECU with chargecooler and water Injection and what not other mods sits at 1 BAR with out any boost control and with the Apexi N1 xhst went up by It self to 1.273 BAR with out any cut out whatsoever! Currenty with the ct 20 b hybrid and large exhaust size side the boost has now gone from 1 BAR to 1.34/1.36 BAR[ *Tested at Rogue Motorsport/Lyndon] but will sort that out with the FC and mapping and or boost control unit to be sorted soon ans just to be safe do not drive past 1.1 bar!!! It's hard not to but WISE! For now!

Point Is this Is with an OEM REV 3 + ECU!

[hagghill]

Mm caution!!!...Most likely If mapped In Japan It Is to their higher octane fuel and yes It Is possible that some one set It to 1 bar but what's the point? Sorry does not sound right. Personally I would have It tweaked and or remaped then you know It's spot on.For all we know some one could have just plugged the FC ECU in with some one elses map; from another MR 2? Unless you have all the dyno graph print out back ground data?

My OEM ECU with chargecooler and water Injection and what not other mods sits at 1 BAR with out any boost control and with the Apexi N1 xhst went up by It self to 1.273 BAR with out any cut out whatsoever! Currenty with the ct 20 b hybrid and large exhaust size side the boost has now gone from 1 BAR to 1.34/1.36 BAR[ *Tested at Rogue Motorsport/Lyndon] but will sort that out with the FC and mapping and or boost control unit to be sorted soon ans just to be safe do not drive past 1.1 bar!!! It's hard not to but WISE! For now!

Point Is this Is with an OEM REV 3 + ECU!

point taken about the higher octane fuels in japan etc, i do have a dynograph in japanese for 300bhp although i have no idea what leverls of boost where used to acheive this?

as i said it was only at 1.1bar that i had problems but at 1bar even on stock plugs it was fine, now ive fitted the colder ngk iridiums although i havnt had chance to hit full boost it should be totally safe at 1bar and if im honest i think thats more than enough for me as i was happy with the cars performance at 0.8bar

[Harry]

i turned the dial a little more earlier and anything upto 1bar was fine and the car really flew but any higher and the yellow/orange light popped on for a second on the dash and it was as if the ignition had been turned off for a split second and lost power (almost like fuel cut)

Been thinking about this whilst making one of my famous steaks and am convinced this It detonation? Would or could that mean under load the Ignition Is too advanced/mapping Issue/s? ref.

[jimGTS]

the power fc doesnt have any form of knock retardation, so with high knock, it wouldnt pull back any timing at all....tho 30 is not high, but high for 0.84bar.
what was it at 1.1bar?


the engine light flickers at anything over 60 in terms of knock afaik....

i would get it remapped for our fuel.

[Harry]

Out of Interest Is there a warning light on the dash for fuel cut or does It just cut the operation? A bit like the rev limiter? Can't get my head around these now.

[jimGTS]

er, am not sure tbh, my fuel cut is setup for like 1.35bar i think....
never hit it....

fuel cut would definatly feel like fuel cut even on a power fc....

[hagghill]

the power fc doesnt have any form of knock retardation, so with high knock, it wouldnt pull back any timing at all....tho 30 is not high, but high for 0.84bar.
what was it at 1.1bar?


the engine light flickers at anything over 60 in terms of knock afaik....

i would get it remapped for our fuel.

im not sure what the knock was at 1.1bar as i didnt have the knock turned on with the power fc but since i fittied the new plugs im getting 27 on the knock running 0.98bar which is much better must have been the stock plugs getting things a bit too hot.

im running 1 bar without any problems at all now

[Harry]

Great