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Gts-t 33 "studdering" & popping noise @ high RPM???

Hey guys, having some issues with my 33 so i thought id get some opinions on what i could look at. All help is appreciated :)

Problem:most times when i take off hard, the car sort of studder and makes popping noise, loosing power at the same time.Usually does it from 4000RPM+.

I tried new spark plugs and my mechanic gapped the plugs, that fixed the problem a bit, but not completely.

:D:):blink::blink::blink::blink:

If anyone has an opinion, feel free, ill listen and make up my mind on where to start.

Thanks in advance to those who will take time to reply. cheers :)

As guilt toy states.

I had the same problem. Was thinking spark plugs or coils. Realised i still had the standard 1.1mm gap as my car wasnt boosted above standard when i got it (1.1mm). Changed plugs to .8mm and it worked perfectly. Was a releaf that i didnt have to buy coilpacks haha

Spark plug gap has been adjusted to .8mm. Fixed the problem but every now and then it comes back. (usually when i got my mates in the car, trying to impress 'em lolll). Is these any point in trying to gap the plugs to .7 or should i go for the coilpacks?

sounds exactly like my r34. i could boost it fine but then the second and third time it would pop and studder and feel like your going no where. i got the new splitfires put in and no problems since. i got them for free and put in for free as well because the dealer said he would before i bought the car. nice car dealer, best ive ever met.

anyway, first i would say check the sparkplugs as its alot cheaper but you said you already have so id say its the coilpacks.

Spark plug gap has been adjusted to .8mm. Fixed the problem but every now and then it comes back. (usually when i got my mates in the car, trying to impress 'em lolll). Is these any point in trying to gap the plugs to .7 or should i go for the coilpacks?

sounds like the heavier load the motor is under is making it even clearer

coil packs

Spark plug gap has been adjusted to .8mm. Fixed the problem but every now and then it comes back. (usually when i got my mates in the car, trying to impress 'em lolll). Is these any point in trying to gap the plugs to .7 or should i go for the coilpacks?

I said .7 not point 8.

Now i am saying .65

Do what i say.

i had a similar problem i put in new plugs and the i silicon up the coils because there were arcing on to the head

i have seen this problem allot and most of the time the coils get replaced i couldn't afford it so i got some hi temp silicon gasket goo and that stopped that problem and yes closing the gap on the plugs will fix the problem 2 a extent a but u dont what the gap to be to close because that causes other problems.

the ignition system on skyline is real bad in my onion i like the old school ignition system with a distributor and coil because it is cheaper there are more options and bigger spark

but any why i see it as u have 2 options use silicon or get new coils

i had a similar problem i put in new plugs and the i silicon up the coils because there were arcing on to the head

i have seen this problem allot and most of the time the coils get replaced i couldn't afford it so i got some hi temp silicon gasket goo and that stopped that problem and yes closing the gap on the plugs will fix the problem 2 a extent a but u dont what the gap to be to close because that causes other problems.

the ignition system on skyline is real bad in my onion i like the old school ignition system with a distributor and coil because it is cheaper there are more options and bigger spark

but any why i see it as u have 2 options use silicon or get new coils

LOL....I to am having the same problem. My engine has 98 km on it and brand new ngk iridiums and its doing the same thing. I beleive that im going to coat it with some urathane.

Ok i can't believe these topics still get brought up when it has been covered so many times before.

The popping/stuttering is called missfire. It is when the spark plug is literally blown out and cannot fire to make a clean burn. Therefore it is a spark issue, ie spark plug or coilpacks.

The stronger the ignition system in the car, the larger the spark plug gap can be because the system can create a larger voltage and ionize the air (gap between the spark plug tips). If the ignition system is weak than it can't ionize the air properly and will not fire, if the gap is too large same thing happens. (Think of a static electricity shock when you get zapped, the potential of the object zapping you is a lot higher then your body and the object tries to reach the same potential between you and it so it ionizes the air and causes a bridge and you get a zap. The larger the potential difference, the greater the zap and the greater the distance between you and the object can be.)

So there are three fixes:

a) if the ignition system is fine, lower the gap between the spark plug tips until it stops missfiring

b) upgrade the ignition system so the spark can fire across the gap properly as yours is obviosly not up to scratch

c) do both

To me if it is still missfiring at 0.8 on such low boost it will most likely be the coilpacks, but you can gap them down furthur to .7 or .6 to solve the problem for the time being, however i'd borrow some coil packs from someone and test them.

As to the iridium plugs, easy fix, don't use them! Iridium/platinum plugs main advantage is that they last a long time compared to coppers. However it is better having a fresh set of plugs in the car all the time than it is to have some sitting in there for years, even if they still work ok. In most modified cars, plugs foul up quickly, so having a set of fresh plugs in the car every 5000-10000km is usually the best option. Also, most iridiums/platinums run a 1.1mm gap which is fine for most stock cars, but with most of us running more boost and airflow over stock, 1.1mm is usually too big and causes issues unless your ignition system is in very great condition. Gapping iridium/platinum plugs is not recommended as it damages the tip of iridium/platinum a lot more than it does to copper.

Just use BCPR6E plugs (or the heat range that you need) that are pre gapped to .8 and change them every 5000-10000km and i can gaurantee the car will run fine (if your ignition system is in good working order) and you'll still have money left over in your pocket with paying $4 a plug compared to $30-$40 a plug.

Edited by PM-R33
The problem got really bad last night, so i decided to drop my boost from 12 to 9psi, now its fine. Still COILS? well i guess i better start looking....

You are starting to annoy me.

Do you want to fix the problem?

If you want to fix the problem, gap your plugs to .65 gap.

Do you understand ?

You are starting to annoy me.

Do you want to fix the problem?

If you want to fix the problem, gap your plugs to .65 gap.

Do you understand ?

Mate, as i said in my first post, i will LISTEN to everyone and make up my mind. I never said i was only going to listen to you so behave mate, i said behave! lol

But anyway i will give it a go (gapping to .65), that will be my first step. :)

Ok i can't believe these topics still get brought up when it has been covered so many times before.

hahah, sorry. Its probably old news to you, but its news to me as i just got the car. Dont know much about it so im trying to catch up. But thanks for the detailed explanation, ill follow it to solve my problems, cheers :)

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