VR4RS probs again!!! hesitate on high rpm

[reintel]

Dear sifus,

need some advise on my problem. when d car stationary, i rev high and it jerks/hesitate on going high between 5800 to 6000 rpm. on 5th gear rpm at 2000, try full throttle and the car tends to jerk, even in high corner it jerks a bit.

today, on the way to work, 5th gear rev to 3000 seems like no power but i do smell petrol so cud it be to much gas or am i running lean. recently when i check on d plug, it looks black & dry.

wats goin on in the engine? need help badly. hope someone can help me here!

 

[lekalo]

methinks its fuelling. If u smell petrol then it's running a lil rich rite?

 

[reintel]

can it bcos clogged fuel filter? when i floor d gas it stall for few sec and then gradually the rpm goes up. doesnt this a sign of lean mixture?

 

[Kenboy]

try swapping a fren's set of plug cables into ur engine and sees if it clears up. hopefully that can solve ur prob.

if not check ur ECU and ignition timing.

if it doesnt, u may want to check whether you are losing engine oil. if you are..u may be in for a hefty fix.

 

[reintel]

Engine Oil - Checked. No problem. I just done major overhaul 1 year ago wif all oem and some racing parts.using Magnatec oil. change every 5000km

Plug cable - replace to NGK aftermarket plu recently. No problem using it for the past 2 months.

plug - replace new and last 2 days ago, open up and clean d plug. plug it in and no problem.

high rpm jerks happen for quite sumtime but it comes and goes so its hard to determine the exact problem.

 

[Kenboy]

only jerks at high rpm?

any backfire or black puffs of smoke when engine misfires?

there are a lot of issues to look at, like whether ur fuel pump is up to the job. if u boost up and ur fuel pump cuts, it can be like this.

and whether the ignition system is up to the job of high rpm high boost as well. u may need to check ur contacters (the 4 banana looking things that connect to ur plug cables.

hard to diagnose over the net. and all this is just my conjecture. good luck.

 

[reintel]

Kenboy,

thats for the feedback. theres no backfire or puff but if going for high rpm theres a bit of black smoke coming up. i up d boost manually when i go for short drag but normally the boost at standard running at 10psi. Im now using EVO3 fuel pump and i think shud b able to cope up wif standard boost.

on the ignition system. this may need pro to help. im not sure how to check it. perhaps will send it to my trusty mechanic to check. at this moment trying to get it solve DIY.

 

[techtic]

did u check ur turbine?? ur piping?? it seems like when u rev, the boost dint want to come out. small holes to the turbine or piping sure will make it turn to jerk when high revving.

 

[reintel]

i did check on d hose but cudnt find any leak. not sure abt the turbo but according to boost meter it did reach to 10psi wif no problem but couple wif jerks of course!

 

[lekalo]

did u check ur turbine?? ur piping?? it seems like when u rev, the boost dint want to come out. small holes to the turbine or piping sure will make it turn to jerk when high revving.

TRUE!! TRUE!!! 4got that piping has a tendency to bocor.. so watch it closely. Any hoses and stuff..

 

[Hangman]

can it bcos clogged fuel filter? when i floor d gas it stall for few sec and then gradually the rpm goes up. doesnt this a sign of lean mixture?

are you using any piggyback or re-chip ECU? If u are then i think its the tuning, ignition timing and fueling.

 

[reintel]

just now sent my car to mechanic, i tried to run high boost and i cud see the car run like diesel turbo... thick black smoke all d way to 6000rpm. havent had time to check out d probs. hope nothng bad happen to the motor!

 

[Hangman]

if like that means to rich already. i dont think anything bad can happen la...rich is better than lean. But if u run rich to long then ure O2 sensor might give way.

 

[Kenboy]

sounds like an ignition problem. fuel not igniting/misfiring.

 

[reintel]

We just found out d problem. apparently the fuel pump had power surge causing it to work overtime and overload on the the injector wif the fuel. My mechanic was saying that this would b 1 of symptom that the pump is gonna die soon. is it true?