injectors

I had some stuttering under high boost (1.3) and at high speed. is this an injector problem, mine are standard.

Stock injectors?

Wasnt yours on hybrids?

Carl, you don't need to post everything under new members *grin*, you have said hello, you are one of us now... use the other sections dude.

Does the car have an AFR gauge? (Air/fuel ratio)

thanks gav I will I just feel so f888ing newbie, I know s888 about supras. all my questions are really basic. but i will use the other sections..

no afr gauge..

and yeah its stock injectors, but hybrids

thanks gav I will I just feel so f888ing newbie, I know s888 about supras. all my questions are really basic. but i will use the other sections..

 

no afr gauge..

 

and yeah its stock injectors, but hybrids

My first recommendation would an AFR gauge and possibly an EGT gauge so you can keep an eye on things.

hmmm i'd rather drive one of you guys around in the know and let you hear / feel what i mean. feel i have enough gauges. but yeah!

What management are you using? Stock ecu or a piggy back or a SAFC or something similar.

When you say stuttering what do you mean? Is your master alarm (the big read triangle) lighting up? Is the engine management light in the right hand side instrument cluster lighting up? I know you have hybrids, but what additional management have you got?

hello class one,

i have toms racing ecu. no master alarm visible.

its just hestition when i try flooring it, letting of the accelation a little cures it. thats why i thought it may be a fuel supply - injector - problem since i still have stock injectors. But im not sure mate.

Carl

At 1.3 bar and stock injectors you are right on the limit of the fueling system, possibly beyond it. If you have a boost controller I'd lower it to 1.2bar and see if the stuttering continues. As Gav mentions an AFR gauge would be a wise investment.

Does it sound like a misfire? It could also be bad plugs.

Is this on the first turbo or with both? I'm wondering if your acutators are sticking a little bit. Is it doing it when the engine is cold or fully warmed up?

As Gav said I would be investing in an AFR and a EGT gauge to keep an eye on things, they can be a useful indicator/monitor. Although once fitted they can also be known as a worry gauge, as you look at them all the time and worry....

At 1.3 bar and stock injectors you are right on the limit of the fueling system, possibly beyond it. If you have a boost controller I'd lower it to 1.2bar and see if the stuttering continues. As Gav mentions an AFR gauge would be a wise investment.

 

Does it sound like a misfire? It could also be bad plugs.

Don't want to confuse the guy, but i was running stock injectors, and was seeing 10 AFR at 1.3 and was still pulling fuel with the emanage, so i would be inclined to think its unlikely to be on the limit,

Also Carl, did you buy the car as a fresh import? what I'm getting at is if it was set up in Japan then i doubt the fuelling is that out,

i would take a look at the plugs, it could be as simple as they need the gaps closing up a bit.

Don't want to confuse the guy, but i was running stock injectors, and was seeing 10 AFR at 1.3 and was still pulling fuel with the emanage, so i would be inclined to think its unlikely to be on the limit,

I was trying to keep thing simple until there's more info, but I know where you're coming from. At high rpm the stock system still runs rich (saw this on my BPU car too), but they run dangerously lean on 2nd turbo spool up in the higher gears.

Perhaps if Carl could let us know the rpm and gear this was happening at we could have a better idea of the potential cause.

My guess would be a spark plug or fuel supply issue (pump or filter not working 100%)

Well class one it would be at highish revs im thinking from about 4k to 7k revs in third or fourth gear at around 80-90 L3Pt0n5 (!).

I could recreate the scenario and repost if im being too vague. I think sensibily I would do well to reduce boost pressure to 1.2 bar max.

Im too newb to know what misfire sounds like, but to me it sounded like the car was saying "Carl you idiot, I know I'm highly modifed and all that but the last guy who modified me left with with standard injectors, so don't take the piss and ease up a bit on the throttle mate".. that kind of sound.

AFR and EGT (what the hell is EGT?) gauges seem to involved to me, rev counter and speed in enough for me, plus im a well known worrier so this won't help - need to keep my eyes on the road.

At the end of the day, its a quirk, i would live with it becuase i can ease up on the gas, but if it is a question of spark plug gapping rather than a costly injector replacement, then it could be worth it.

Also I flagged it up just in case you were gonna say "Carl, that sound means your car is about to blow up".

And class one, the engine was fully warm.

Did the 'stuttering' happen during the spool up area on the 2nd turbo (4k-4.8k rpm)? or it is when peak boost pressure has already been reached? From what you say (3rd or 4th gear) it's not when the engine is under it's highest load (that would be in 5th or 6th) so seems to be quite a serious problem.

If it's only occuring after peak boost pressure has been reached then as mentioned it'll either be a spark or fuel supply issue. Can you check which plugs (exact model) and the gap they're set too? It should give us a guide if you have the correct setup.

Do you know if the fuel pump has been replaced or uprated (an uprated is required for jspecs using high boost), also has the fuel filter been replaced recently? If not then get both those done before using more than 1 bar.

Please be as specific as possible since it could either be a very simple and easy issue to fix or a very serious and very expensive issue. A misfire will almost certainly be caused by the plugs, if it's det then the engine is going to melt eventually. The 2JZ-GTE is very, very strong but you need to ensure it's not detting otherwise is a timebomb.

The Toms ECU seems to run a more aggresive ignition map so you need to ensure everything is running perfect.

EGT = Exhaust Gas Temperature

AFR = Air Fuel Ratio

As said I would reduce the boost to 1.2bar for normal driving. Do you know what type/temp of plus are fitted?

I'm no expert as you have gathered, but I'd say it was peak boost pressure, i was practically (almost) flooring it, thats when the car started its protestations.

well the plug gap i will work on with a mechanic and get you the statistics so you can make an informed diagnosis, if i wish to seriously resolve this problem.

I will look at the paperwork and see about the fuel pump and fuel filter, or contact the previous owner.

Greatfully,

Carl.

EGT = Exhaust Gas Temperature

 

AFR = Air Fuel Ratio

 

As said I would reduce the boost to 1.2bar for normal driving. Do you know what type/temp of plus are fitted?

thanks nic,

no not sure bout the plugs but will post more info here when i know.

thank you very much!

update: it as a walbro fuel pump.

not sure about the filter.

my question now has to be.. if there is no early/ late detonation (detting?!), then what damage will be done if it is simply a case of the injectors being to small so they can't supply the level of fuel needed under near full throttle conditions?

I would not worry about the injectors ATM but would suggest (as others have) you check the plugs ASAP

thanks CJ, will look into getting that proffesionally done (I dont know where to locate them, or how to measure the gap)

Carl

thanks CJ, will look into getting that proffesionally done (I dont know where to locate them, or how to measure the gap)

 

Carl

I am not too sure where you live but Phoenix at Watford come highly recommended. Or, alternatively, maybe a member living close by can help you do it yourself? It isn't a particularly difficult job but is is a bugger the first time round.

Thanks mate. If it was spark plug gapping would the symptoms of accelation hesitation get worse under high boost (1.3 bar)? Or is det the symptom of bad plug gapping?

Thanks mate. If it was spark plug gapping would the symptoms of accelation hesitation get worse under high boost (1.3 bar)? Or is det the symptom of bad plug gapping?

IMHO, I think the problem you are seeing is the plugs / spark breaking down at higher boost. My bet would be that a new set of plugs will see that eliminated.

Ok dude, will have to get this checked in due course. thanks again - really helpful. Not really driving it anyway at the moment, need to get it raised. Plus its hissing down with rain and is freezing here.