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2jzgte hesitating under boost


jza800

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Yes that would be the easy choise, But want to fix it my self, so i can lean off i myself. And it cant be true noone have testet Thir plugs. And this is a forum, where we should help one and another, insted of just say take it to a shop, if you no the answer, why just not just wrote that in, instad of go to shop, maybe you dont agree how i do it But please accpt i want to fix it my self with all the help i can get inhere

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That's not a viable test for plugs. It may show a carbon or conductive trace on the ceramic, but it doesn't show ho the plug is behaving at combustion temperatures, under combustion pressures, igniting a fuel / air mixture, with pulsed HV applied. That's the job of the oscilloscope and pick up coil on the coil pack.

 

Just renew them, or have them blasted in a proper plug blasting machine. These seem rare nowadays, people look at mine as if it's something from another planet ;)

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That's not a viable test for plugs. It may show a carbon or conductive trace on the ceramic, but it doesn't show ho the plug is behaving at combustion temperatures, under combustion pressures, igniting a fuel / air mixture, with pulsed HV applied. That's the job of the oscilloscope and pick up coil on the coil pack.

 

Just renew them, or have them blasted in a proper plug blasting machine. These seem rare nowadays, people look at mine as if it's something from another planet ;)

4

 

I appreciate the explanation alot, i now that that was not the right way to do it,, but maybe some with understanding for plugs, could see that maybe some off the plugs seems to was/is bad, just looking at the messument i did on them.. so i was able to veryfi that i maybe had some plugs that maybe only had 85% off funktions back, that could explain that they maybe could make some hesitation when i go to boost.. but i can now understand it is not just to trubleshoot without the right tools :(

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OEM coil packs aren't cheap, but they are the best.

 

Forget the aftermarked ; I paid my lessons before .. don't do the same mistake mate. You'll pay twice in the end.

 

Do it once right.

 

Check Nic's link : you can get 6 for 475$

 

yes i have seen that, and will consider it strongly if the problem solves with the plugs..

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Can you not just borrow a set or even a single coil pack from someone to take these out of the equation?

 

Not all aftermarket ones are crap, despite popular belief. I have been running a set of unbranded copies now on mine for over two years with great results at BPU and in that 2 years most of the miles have been pedal to the floor from a standing start on a strip. Its under these conditions that a coilpack that is breaking down will normally cause a miss.

 

Have you taken the silicon sleeve off and looked very carefully at the end of the coil pack where it goes over the spark plug? I am sure you will see minute cracking there, this is where the high tension is escaping and tracking to earth.

 

One trick I did on my old ones before I replaced them was to put 2 layers of good quality heatshrink over the end of the coil pack, under the silicon sleeve/boot thing. This worked perfectly on mine and cured the misfire completely while I was waiting for the replacements to arrive.

 

Those cracks you show around the fixing lugs, although horrible and show your packs to be clapped out, are unlikely to be where the HT is leaking from btw. Its more likely to be the plug end.

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I have looked on the ends off the coil packs, and you are right, there are cracks on all off them, i have taken some iso tape as you use when you soilder joints on wirring.. but that hasent fix my sparks mis.. maybe that is to thin i dont now.. i have now tried the water mod in a spraycan, and i can hear after a while the spark going out off the coil, but where i dont now as i cant see that..

 

so i seems like i have to get new coils..

 

what coils have you tried???

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I have looked on the ends off the coil packs, and you are right, there are cracks on all off them, i have taken some iso tape as you use when you soilder joints on wirring.. but that hasent fix my sparks mis.. maybe that is to thin i dont now.. i have now tried the water mod in a spraycan, and i can hear after a while the spark going out off the coil, but where i dont now as i cant see that..

 

so i seems like i have to get new coils..

 

what coils have you tried???

 

If its the coils, and it certainly sounds likely if you can hear it then forget tape, it wont have the insulation properties you require at these voltages and will just pass through.

 

Give them a thorough clean in isopropyl alcohol making sure they are absolutely spotlessly clean and dry and then put at least 2 layers of decent heatshrink over the ends and they MAY be ok for a while and get you going again. Running a lower boost until you replace them will help.

 

I am unable to steer you to the exact ones I used, sorry.

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i cant go lower boost, as it is stock boost level..

 

i did nothing to the coil rather that just put the tape on, and i usede tape you use to wirring, when you have soldered the wirring..

 

but can you then say how it is posible that i can run normal, when the engine light is on?? should it not give the same symtoms, light on or not ? or does the ecu go and do something when the light is on?

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Nah, surely not? ;)

 

"The fact they are cracked may mean the HT is escaping and tracking to ground under load. They DEFINITELY should be changed!!"

 

LOL

 

as said my mind had a hard time to understand that, when it worked fine with the engine light on, but when i did see and heard the the engine cut out, when i used the water, there was no more excuse to not changning them.. may sound stupid, but that how i work.. what to find the fault before i just change lot off parts.. :D

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i would say plugs clips and they coil ;) but i now what you mean..

 

 

now i just have to find the reson way my seq dont work.. so vsv here we come..

 

but if i have it in ttc, and both valves are open, are can stay that way for over a week, can i then have a vacum leak? or is it one off my vsv that dont work..

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when you put the car in ttc mode, i now i am eliminates the vsv from the system, but what i mean is, when i put it in ttc mode, the egcv vsv and the iacv vsv stayes open.. from the other engine i had those vsv closede within a week, mean that there should be a leak somewhere, and with the new engine, the vsv stayes open, iven after a week, so that should mean that i dont have a leak somewhere... so that leads me back to some vsv dont work as they should..

 

hope you understand now :)

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  • 10 months later...

I thought my problem was solved, but now I have hesitating trouble again, under boost about 3200 to 3800 rpm it hesitating twice i can feel it in 3 and 4th gear, but only when engine light is not on, as soon as my engine light turn on, no problem at all, it pull strong and hard and no hesitating at all.. and the error code i get is speed sensor, so it is not realetet to my problem.. i have changed my coils to superspark coils.. the coil is new , clips is new , and i run NGK PFR7B spark plug..

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  • 2 weeks later...

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