4G63T Jerking

[evo3]

Hi, i need help on this.

When my car is running normally (no boosting :rolleyes: ) that it run Ok but when u suddenly boost the car, it will start jerking (sometime only). :( DO any Sifu here know this problem?

Thanks :D

P/S: Engine 4G63T standard no mod except HKS SQV n HKS Powerflow. Boost at 0.6Bar only :unsure:

 

[ezwong2002]

your spark plugs i think not working properly...

check ur plug cables too.

turbo cars usually need No.7 plugs.. but it suxs when the engine is cold.

or invest in iridium plugs.. denso, hks, ngk...etc etc.

 

[evo3]

thx....

FYI, i using the spark plug that come with the half cut for two years liaw, well i think it time to change it.... :P

 

[ezwong2002]

hehehe.. if after change to better spark plugs.. improve ur performance.. please keep us informed. :)

 

[evo3]

hehehe....sure sure....will change mine to Greedy spark plug cos can pay in installments :P cos my workshop is an authorised Greedy outlet.. :(
i prefer HKS spark better..hehehe..

ne way will post the outcome soon..... :)

 

[Joeker]

Car jerk under boost, many possible causes. Mostly either due to the fuelling or ignition.

Since everybody talking about spark plugs, check the plug gap. Improper gaps will misfire under boost.

 

[vestax]

use back the standard oem NGK BPR7ES or BPR6ES copper plug's and gap it to 0.28 will be the best setup .

 

[Danny]

recently found out my jerking problem was due to one of the plug gap is out, also fuelling related. Using NGK 6E-11

 

[evo3]

hehe...what is the other possible causes ahh? need to be sure ma....so next time know wat wrong with it.... :D

 

[Danny]

can also be caused if one of your hose/piping is loose ie. leaking air. Your car will feel extremely sluggish and then your car engine will just stop suddenly.

 

[evo3]

ahhhh...will check on that too..... :D

 

[ezwong2002]

still not yet change sparks plugs?? aiyoh.. change s/p first and see how..

 

[evo3]

no money ohhh..have to wait till next week for gaji to come in..hehehehe
not like u so rich ma... B)

 

[ezwong2002]

haha.. i rich? leech can ah... i'll suck ur blood .. :lol: aiyah.. change the NGK No.7 first lah.. baru RM35 niah.. haha.. den later baru tukar iridium plugs..

 

[Danny]

ezwong, does your car feel sluggish during cold starts with standard ngk7? Since they are colder plugs. I'm still using NGK6.

 

[evo3]

ehhh...so cheap ma....NGK7?..afterward finish work go check the price..hehehe
per pc or whole set?

 

[Joeker]

Originally posted by Danny@Jul 24 2004, 11:31 AM
ezwong, does your car feel sluggish during cold starts with standard ngk7? Since they are colder plugs. I'm still using NGK6.

Alot of misconcepts about "Cold plugs".

The plugs itself does not radiate heat. Colder plugs are able to stand up higher combustion temperature rather than turning into a C.I engine glow plug and colder plugs have better heat dispersing capability.

It will not have any affect on cold starts.

 

[Danny]

how about more likelyhood of fuel contamination on standard cold plugs(not iridium tip)? Is that a misconception as well?

 

[Joeker]

Then you have to look into the air fuel ratio.

Unless you are burning way too rich to begin with, its unlikely your plugs will be coated with thick layers of carbon from uncombusted fuel.

But make sure if the plugs are fouled by carbon or sooty thick black goo. The former indicates rich while the latter could be a tell tale sign that you're burning too much engine lube.

 

[ezwong2002]

Originally posted by Danny@Jul 24 2004, 11:31 AM
ezwong, does your car feel sluggish during cold starts with standard ngk7? Since they are colder plugs. I'm still using NGK6.

i'm not using No.7 plugs in my car, my fren with GSR engine is.. and yes.. it's sluggish with cold-starts.. have to wait around 5-10mins to get it warmed-up. after that.. it's like normal, but according to my fren.. if he use No.6 plugs.. when he does high-rev the car jerks. after using No.7 plugs the problem of jerking went away.

EVO3, yeah RM35 for 4pcs