HELP on my 4g93t engine......

[playboy23]

Im having a problem with my car 4 da past 2 weeks....
i ve got no idea wat 2 do next so i ve decided to seek 4 advise or help from the fellow forumers..

I juz converted my engine 2 months back, its a 4g93t/ 1.8 gsr turbo
Wen i drive in normal acceleration mode da engine is smooth BUT
Wen i start to boost higher, it will "semput"/ misfire/ pop pop sound from the exhaust n i have 2 let go my accelerator n accelerate slowly again.

i ve juz consulted a mechanic tat is only familiar wit stock standard cars..
at first he said da airflow sensor got problem, n i changed da airflow sensor, AFTER tat the engine was smooth, BUT sadly it only lasted 2 weeks only, da problem appeared AGAIN, i bought another airflow sensor n installed it BUT its da same, da problem is still there....
Not even that, Few hours after tat disaster strikes, my car brokedown wen i was driving, couldnt start, Towed da car back 2 da workshop, checked n found out tat the power unit(located beside the coil) was faulty, replaced the power unit(secondhand) n da car starts but da problem is still there. Ive changed da petrol filter also.

NOW i ve gone into a dead end n seeking for da forumers n sifus advice n help to solve my problem. Hope ya guys can help me out wit this... Mayb u guys can suggest me a good mechanic or workshop tat i can go.
Thank a lot 4 reading my thread....

 

[SYeNi69]

Did u try checking the Fuel Pump

 

[Shanashi]

Fuel Pump
Dirty Fuel Injectors
Dirty Throttle Body
Air flow sensor Spark plugs
Spark plug cables

 

[playboy23]

thanx SYeNi69 and Shanashi

already checked the Throttle body
already checked the Spark plugs
already checked the Spark plug cables

now left 2 check the Fuel Pump, Fuel Injectors

u guys noe any place 2 service the injectors???
thank you

 

[kherz]

can be dirty fuel tank..
happened to me last time...

 

[zamiex]

try change/swap cable plug,plug,coil..

 

[chrissyong]

thanx SYeNi69 and Shanashi

already checked the Throttle body
already checked the Spark plugs
already checked the Spark plug cables

now left 2 check the Fuel Pump, Fuel Injectors

u guys noe any place 2 service the injectors???
thank you

ok~you got check the basic thing like fuel filter?try change brand new fuel filter at engine fire wall they,the fuel pump is need check the frequency by meter~injector hard to check,only one way u take out injector to sunway wash and clean your injector~

 

[ftzone]

i'd say your cheap spark plugs... they cannot last in turbo engines.. try iridium power plugs.. they are a much better investment and choice.

the other thing to look at is your blow off valve. be it stock or aftermarket.. it could be leaking.

 

[EvoGanu]

from my experience... u need to change ur cable plug, try to use ur friend cable plug (good cond) if still happend then try to change to better plug.

like ftzone said, turbo engine very sensitive, can be use for start the engine but cant boost consistently.

 

[ehem]

standard 4g93t engine? or modified engine? might be because already modified thats why got these problems..? spark plugs matches with engine set up or not? checked ur ignition coil resistance is within spec? fuel pressure ok thruout rev range? using fuel with enough octane level? ur compression standard? intake air temperature ok? if got spare ECU try to swap... it can be a lot of things, but definitely will be a lot of headache..

ur sympthoms is back firing when boost is building up right? best is send it for dyno run... then can see ur afr.. also monitor engine temperature, knock sensor, fuel pressure, these things can tell u more or less whats goin on with ur engine.

 

[chrissyong]

i'd say your cheap spark plugs... they cannot last in turbo engines.. try iridium power plugs.. they are a much better investment and choice.

the other thing to look at is your blow off valve. be it stock or aftermarket.. it could be leaking.

plug is almost same one,but don use the recondition plug~if the normal plug like 4-6 code is hot plug easy for start engine and one the road but water temp will be a bit hi,if the plug code like 7-9 is cool plug will get better hi rpm power and great initial power and the water temp will low,the worst thing is you must standby 2 or 3 set plug for spare,the 7-9 code plug will very easy to get wet or dirty,cause the initial power is damn low at low rpm and hard to start engine at morning time,cheaper not mean is bad,cause last time my friend ah ka skyline also use rm5 motorbike TZM plug only,damn nice also,deepend what you need,he said turbo kick in time will feel like sumbat (jerking) almost is fuel problem,this is my real live experience,plug in A/F ratio wide band will know what problem~

 

[ftzone]

spark plugs are manufactured based on different material used for specific applications. they are not the same. if Iridium plugs offer no additional advantages compared to the MYR48 per set ayam brand plugs.. I would have purchase the MYR48 plugs instead right? This is because alot of turbo cars I have tuned or serviced experience problems similar to what playboy23 mentioned. After a change of fresh iridium powered spark plugs the problem is gone. Other possibility of part failure will also contribute to the jerking problem under boost not just spark plugs.. but why don't we try the easy way to solve the problem and not by sticking a wideband o2 sensor because not everyone have that kind of tool to diagnose a problem.

for turbo charged engines such as the 4G93T it will require better quality spark plugs especially when you have already increase the boost above factory specs.

so playboy23 where is your location? if you are in Penang area, you are most welcomed to drop by my place for a check-up. and I impose no charge if your problem isn't solved.

 

[playboy23]

kherz : already changed da fuel filter which was quite dirty, but still da same

zamiex : spark plug cable check d bro, its in ok condition

chrissyong: yup its down 2 da fuel pump n injector only, im gonna get da fuel pressure checked n also gonna clean da injector soon...

ftzone: im currently using denso iridium plugs bro. my location is damansara bro.. quite far from ur place, thanx 4 da offer anyway

EvoGanu : spark plug n cables already checked bro

ehem: its a standard 4g93t bro, only extra mod is da turbine(tdo5h), evo3 fuel tank with evo3 fuel pump, evo 3 injectors. wow in tat case i ve got a long way 2 go 2 check all those stuff u mentioned bro....

Thank u guys for ur advise, i juz consulted a mechanic yesterday n he test drive my car n said it might be because im running on a rich mixture of fuel, bcoz of da EVO3 510cc injectors, he said even rich fuel mixture can cause tat problem, now i guess i have 2 concentrate on the fuel system whether its running in a rich fuel mixture or not, he also said tat i need 2 use a piggyback 2 tune da a/f ration bcoz of the big cc injectors and also coz im only running using stock setup

 

[ehem]

kherz : already changed da fuel filter which was quite dirty, but still da same

zamiex : spark plug cable check d bro, its in ok condition

chrissyong: yup its down 2 da fuel pump n injector only, im gonna get da fuel pressure checked n also gonna clean da injector soon...

ftzone: im currently using denso iridium plugs bro. my location is damansara bro.. quite far from ur place, thanx 4 da offer anyway

EvoGanu : spark plug n cables already checked bro

ehem: its a standard 4g93t bro, only extra mod is da turbine(tdo5h), evo3 fuel tank with evo3 fuel pump, evo 3 injectors. wow in tat case i ve got a long way 2 go 2 check all those stuff u mentioned bro....

Thank u guys for ur advise, i juz consulted a mechanic yesterday n he test drive my car n said it might be because im running on a rich mixture of fuel, bcoz of da EVO3 510cc injectors, he said even rich fuel mixture can cause tat problem, now i guess i have 2 concentrate on the fuel system whether its running in a rich fuel mixture or not, he also said tat i need 2 use a piggyback 2 tune da a/f ration bcoz of the big cc injectors and also coz im only running using stock setup

ur ONLY extra mod also quite NOT bad... haha.. seems like ur almost prepared to run more boost.. (evil grin)... yup, ur mech can be right.. bigger injectors, more-flow fuel pump... but funny that it only happens when ur building boost... but still, it sounds like a logical reason. i thought sunway(nearby to damansara right?) got dyno shop? dyno it out at the same time when u install ur piggyback then... nothing beats the feeling when u got OFFICIAL dyno figures for ur bragging rights.. haha

 

[ftzone]

duh... 510cc injectors with stock GSR ECU + Air Flow?
That is the problem la.... piggyback ECU needed to control fuelling.
You can take out your spark plugs and see if the tip is full of carbon deposits.. if yes confirm too rich.

 

[Syahz]

Stock ECU can't control the Fuel and Ignition when the Boost Coming.Put the Haltech Sprint 500 or Microtech LT10s la bro.U can control all the way...la bai.

 

[zamiex]

try swapping back to 390 injectors..or if u have fuel regulator try lowering the pressure abit but still need to do wideband ler.. my pomen can check with wideband if u want laa

 

[Guam135i]

My car is in the Philippines and it recently received a 4G93T conversion. Now the car runs like the injectors are clogged. According to the mechanic the problem is that the fuel tank is dirty and has clogged the injectors. According to him I should replace the fuel tank. I was thinking instead of buying a used also old fule tank I should just buy a fuel cell. Waht do you guys think and is there a fule pump recommended? Would anybody know what is the flow rate of the stock injectors of the motor? I am new to this motor so sorry for all the newbie questions.

Thanks,

 

[Mat Indera]

Playboy123, what is the solution bro?