Engine Light Flashes When High Boost

[Jack-]

Hey guys, recently bought a r34 gtt and I've found when hitting high boost the engine light flahses on and off until i let it off boost.

It has a Z32 and a power FC and is on half a bar of boost.

Previous owner said it is tuned to run on 98 and I put a quarter of a tank of 95 (couldn't find 98 at the time), could this be the issue as the tunes set up for 98? or could it be faulty AFM or something else? I'm scared to put my foot down in boost, don't wanna break anything.

Any help is appreciated

[Bsa]

Put octane booster or 98 in it before putting your foot down if it's tuned to run 98 its a must I suggest not driving on boost at all as it will be running lean

Edited February 3, 2012 by Bsa

[Dajae]

Your engine is knocking. If its tuned for 98 and you have no other choice but plain old 95, dont push it at all.

If you push it you risk detonation damage to your pistons if it happens for too long.

Engine light flaahing is the pfc telling you its knocking. Do you have a hand controller?

Ty.

[Duncan]

+1, your engine is pinging and it is extremely dangerous.

turn the boost down (or even off), don't use full throttle until you have refilled the tank with 98.

If it still pings (light flashing) after a new tank of 98 octane, you need to get the computer re-tuned on a dyno

[Jack-]

alright cool I'll turn the boost off and drive the tank right down tip fuel light then put 98 in it

[jiffo]

Just use the hand commander and pull a couple of degrees timing out of it until you can do a complete fill with 98.

Go Settings then Ign/Inj and take some timing out of it.

These temporary changes are deleted as soon as you turn the engine off, all good, tune is unaltered.

That's what this function is for, trial tweaks that can be instantly erased.

[Dajae]

.. Going on the assumption that he has a hand controller.

Definately a good band-aid fix for now, thats for sure. Dont wait until you're on empty to put 98 in.. Might as well do it now. You might be diluting the 98, but 96.5 (as an example) octane is better than 95.

+1 what Duncan said. You might as well get it tuned up anyway. Preventative maintenance is always a good thing.

Ty.

[DVS JEZ]

Blake using 95 won't make it run lean but 95 has a lower knock resistance.

OP has the engine light ever flashed before with 98 octane?

the engine light can flash due to :

high knock

afm maxing out

injectors maxing out

i doubt on 7psi that the inj or afm are maxing out..

do you have a hand controller?

[Jack-]

just bought the car... it's got a boost controller and another gizmo to do with the power fc... it's only on like .6 bar. not sure if it flashed previous... Been driving it around avoiding boost and I'll fill it tomorrow a full tank of 98.... think it has about a quarter on the gauge of 95

will be booking it in for a service next week at chasers n see what they think if the 98 doesn't fix it by then and just drive the daily til then

thanks guys appreciate the help!

[FordyR31]

Half bar boost. Isn't that factory anyway? Its about 7psi. If that's the case try a stock ecu and see if it still does it.

[Dajae]

He has a pfc. Why would he step backwards? Tune tidy-up wont cost much

Jack-, dont feel like you gotta wait to put 98 in. Raising the octane level any way you can will only help

Ty.

[Dose Pipe Sutututu]

Or maybe the previous owner just installed a PowerFC without doing any tuning. The stock ignition map is super aggressive on them.

When he/she said tune, did he or she just poke about with the AFM setting and part of the injection map?

[Piggaz]

Take the return line off the arse end of the FPR, put a longer hose on te reg, start car and drain into a Jerry. Put the fuel in the daily and fill up with 98.

Job done.

[JonnoHR31]

Take the return line off the arse end of the FPR, put a longer hose on te reg, start car and drain into a Jerry. Put the fuel in the daily and fill up with 98.

Job done.

this. unless your patient enough to drive it sedately until empty, which most people arent.

dont use any sort of octane booster, will only cause more trouble.

[FordyR31]

I wasn't suggesting he use the stock ecu all the time... Just suggesting he try it out to trouble shoot and see if the engine light still comes on under boost. Like trying a different AFM to see if your AFM is stuffed..... Try a different ecu to see if its the tune/ecu or something else. Considering the current owner bought it this way it may help it may not. If he is going to get it re-tuned why not get it tuned on a lesser octane fuel then always use 98 octane?

[SargeRX8]

I wasn't suggesting he use the stock ecu all the time... Just suggesting he try it out to trouble shoot and see if the engine light still comes on under boost. Like trying a different AFM to see if your AFM is stuffed..... Try a different ecu to see if its the tune/ecu or something else. Considering the current owner bought it this way it may help it may not. If he is going to get it re-tuned why not get it tuned on a lesser octane fuel then always use 98 octane?

The stock ecu doesn't flash the engine light when it knocks. I really doubt there is a tune on the ecu. I recon its the stock pfc map. None the less, your car is pinging. Change the fuel or use the hand controller to get rid of some timing.