help: 3sgte boost / "hesitation" at multiple point

[gt-trainer]

this is interesting,our caldina is starting to feel "flat" at higher rpm,s its ok round town but push it flat in fourth on motorway and it has a hesitation and seems gutless,also above 3000 rpm its sluggish.could this be the same problem?may gotta get sum plugs aye.

[fivebob]

pulled plugs and heres what they look like... distinct rust colour to them - even more than shows in the image... what causes this type of phenomenon?

Have you run Octane Booster in the engine? If you have, then it was probably Ferrocine based.

0.8 gap is the maximum I would run. 0.7 if you're running higher than 16psi.

[TWSTD]

Well guess what - put my old plugs back in (denso iridium 6's that came in it from japan) and its fine again - hesitation on boost all gone.

My plugs were not wet at all - they were bone dry and only one of the coil boots had any hint of dirt on it. There looks to be more of a flakey rust like deposit on my plug than yours Melissa.

So what gap are we supposed to run in these (altho remmeber plug gap is less important with iridium plugs as the spark can jump a lot easier with the tiny pointed electrode.

I may stop my down a bit to 0.9 or 0.8 in case they decide to foul again... cos stuff spending $70 every 6-8 months on replacement iridium plugs!!!!

[vvega]

wicked dude glad it all worked out


v

[TWSTD]

Have you run Octane Booster in the engine? If you have, then it was probably Ferrocine based.

Yep - ive run a couple lots through - so that could have caused the depsoits on the plugs aye? I will stop these plugs down tomorrow nite.

Thanks all for your advice etc - glad shes back to normal with such an easy fix! - dont ya just love this club

[tsenior]

Mine has the same hesitation problem under boost put my plugs are NGK Iridium BKR6EIX and these were already gapped to looks like .75, the original denso plugs i pulled are DENSO PK20R8 (.8 gap) which is confusing me, What is the proper heat range? I have a Gizzmo EBC which seems to be near impossible to keep stable boost... rising up and down when on hard acceleration.

Also under inspection the Plug which is far right looking from front of engine bay had oil on it, Whys that? Do i need a Catch can because i noticed oil residue in the throttle body, also oil residue in the turbo intake, Are my seals gone and making my mixture shit?

has anyone had luck with Gizzmo EBC, I can turn gain down and makes it more stable but boost comes on slow. so seems to be slow boost more stable or fast boost really unstable and all over the show.

Any ideas??

[Mr Revhead]

those densos are the correct plug
and 0.8mm is the factory gap.

theres another 3sgte (sw20) owner in nelson with the same gizzmo issue....
hes resolved. he threw it away.

[fivebob]

Also under inspection the Plug which is far right looking from front of engine bay had oil on it, Whys that? Do i need a Catch can because i noticed oil residue in the throttle body, also oil residue in the turbo intake, Are my seals gone and making my mixture sh*t?

Do a compression or leakdown test, chances are you have cracked ringlands as that's a common cause of oil in the intake

[tsenior]

ok ill do a compression test, I have seen your posts about ringlands So Gizzmo is crap, well thats good to know.. maybe time for a upgrade , if compression is down on that cylinder, What pistons do you recommend for the caldina?

are forged piston ringlands stronger?

could be another 3sgte death on the way! just going to do a road trip as well this week.

so is my current iridium plugs i have in there is the heat range alright?

[Santa'sBoostinSleigh]

my sleigh gets its daily thrashings on 95 octane and i dont seem to have any problems....yet..

[fivebob]

ok ill do a compression test, I have seen your posts about ringlands So Gizzmo is crap, well thats good to know.. maybe time for a upgrade , if compression is down on that cylinder, What pistons do you recommend for the caldina?

are forged piston ringlands stronger?

Piston selection depends on what you intend to do with the car, street driven cars with forged pistons are a PITA and don't tend to last that well.

I'd recommend stock pistons, or or ones forged out of a high silicon alloy like 4032. If using the stock ones then run a minimum of 98 octane, keep the boost stock, or run a decent aftermarket ECU.

Forged low silicon pistons are mechanically stronger as the are more likely to deform, but less capable of handling high heat situations, which is why you find truck pistons made from very high silicon alloys.

[fivebob]

my sleigh gets its daily thrashings on 95 octane and i dont seem to have any problems....yet..

I'm glad you qualified that, because it's only a matter of time if you're running more than stock boost and 95 octane gas on that engine. Stock boost should be Ok though.

[Santa'sBoostinSleigh]

my sleigh gets its daily thrashings on 95 octane and i dont seem to have any problems....yet..

I'm glad you qualified that, because it's only a matter of time if you're running more than stock boost and 95 octane gas on that engine. Stock boost should be Ok though.

motor is completely stock, bar a externally venting BOV
was gunna go front mount to try cool the charge a bit more, but too much effort

[XERO]

my sleigh gets its daily thrashings on 95 octane and i dont seem to have any problems....yet..

Dude even i run mine on 98... Its just happier that way...

Good to see you got her fixed al, did you end up getting her dyno'd??

[tsenior]

well i have just got a New Custom stainless manifold made, custom downipe New Garrett T3,stage 2 turbine,0.48 turbine housing,dry bearing body,compressor is Super 60 trim 49mm inducer with a large 70mm back diameter. New Font TRD Bumper wich doesnt fit any intercooler, so cheap brand new 450x300 autobarn intercooler up for sale as im getting custom made 600x160x90 one built. this stuff was just to fix the leaky manifold syndrome which i have rangied a fix and seems to be working well, none of this stuff is in the car , was unsure how it would perform because i thought the caldina had ceramic implellers .. so was thinking of maybe using a garret ball bearing of some description.

oh was not thinking on raising the boost above 15 psi

so do i qaulify for forged pistions? have Auto and reading on this forum seems to be impossible to install aftermarket ecu, might give a piggy back ecu ago see how much adjustment i can get with that.

[MrOizo]

Are you just doing these mods so you can say you have a reason for Forged Pistons?

[Santa'sBoostinSleigh]

95 is all we have in this shitty region


and tsenior, do a search of fivebobs posts about teh ECU, the answer is MoTeC

[tsenior]

lol MrOizo, if you read my post properly you will see im doing the mods just to fix the leaky manifold.

[tsenior]

what is the easiest way to turn the fuel off for me to test compession, I did it with fuel still connected just to play, and got 132 130 125 135 this was on a warm engine, the 125 one i did again but i noticed it goes up more if i crank longer up to 150 now i dont know if this is the fuel being injected or the other tests i didnt crank for very long or what. Can you explain correct procedure

[fivebob]

With those numbers I don't think you have a problem with broken ringlands. IME you would get something like 165,50,165,165 if it did have that problem.


Correct procedure is to disconnect the injectors, but that's a PITA so just unplug the ECU, which is behind the glovebox (pull the hinge pins out from the bottom of the glovebox to remove it). Remove all the sparkplugs, connect the compression gauge, apply full throttle and crank for at least 10 rotations of the engine (5 compression cycles). You should make sure your battery is fully charged before doing this as it can affect the reading otherwise.

You're not really looking for any specific number, more that they all read close to the same value. In saying that it should be above 150psi.