[Fabbz]

Hey guys,

Noticed my first prob on the 1JZ in a while. Runs perfet up to about 13psi, but when running anything more than 13psi, the car breaks down. It will go on boost and sound like its running on 5cylinders then suddenly back to 6. It will go brrr a few times throughout the rev range when flat to the floot. The exhaust note changes to a deeper brrr sound and there is loss of power. If I hold the throttle say 75% down then it will still make 15psi and the break down doesnt occur, it is only at WOT. Im thinking loose or busted coil pack?

I have a power FC, and this issue doesnt seem to change the knock value or anything like that. My injector duty cycel does max out occasionally, but the issue still happens when the injectors peak at say only 92% Some days at 15psi this issue doesnt happen at all, but more often it does.

Im BPU 1JZ, with Power FC with about 330rwhp.

Any ideas? Cheers!

 

[KingCobra]

Have you eyeball inspected the coil packs for cracks?

 

[Fabbz]

Yes I have had a quick look and all looks in order. Mind you I might take another look.

 

[HamsMKIV]

Another member here mentioned that he applied epoxy to the coil packs and found the arching went away. You might try the same.

 

[Fabbz]

Another member here mentioned that he applied epoxy to the coil packs and found the arching went away. You might try the same.

Yeah....cheers, I think this is a known 1JZ issue and I remember reading a post about it somewhere. Am searching it out.

 

[HamsMKIV]

Well it's a cheaper solution than replacing them. I would only replace them as a last resort considering it will run you about 550 AUD for all 6 new.

 

[Fabbz]

Mmmm, how do I do this? Smear epoxy on the coil boots or something. $550 AUD is not too bad, but will def be trying the resin/epoxy idea first.

 

[mobes]

Look for hairline cracks under the boots. If they're present, epoxy over them.

 

[annoyingrob]

I was the one who epoxied the coil packs, and it worked great.

Take out the packs, and clean them up. Then mix up a bunch of epoxy, and spread it across any cracks you can see. Don't forget to take off the liele blue rubber boots and check under there too. Let it cure overnight, and put it all back together.

It's interesting that your problem is happening only at WOT. It may not be the coil packs, but let's eliminate the easy things first.

A little OT, but my friend had a coil pack replaced on his 02 corolla for the same reason. I told him that he should have tried epoxying it first, or atleast changing it himself because it take 2 minutes, but ended up getting ripped out the rear by a mechanic to replace it.

 

[ZaZZn]

Ok bringing this up from the dead...
I have 18 coil packs.

6 form my 1jz, 6 form my aristo and 6 form my supra.

EVERY single one has hair line cracks... Fortunatly the aristo one's are still working without breakup. HOWEVER, I think that just ended because the DLI is giving them so much more voltage (swapped the aristo ones in to the supra)

The supra ones now can't sustain more then 15 PSI before breaking up even in the aristo...

12 coils =1000$ that I don't want to part with after just spending 3000 this weekend replacing a turbo and having the car retuned.

What kind of epoxy did you use? Where did you get it.... and why the hell are the coils so crap? Is there an alternative COP that we can use?

 

[sai_supra1jz]

It could be other things as well....i use to have that problem...how about your spark plugs. They could be incorrectly gapped or used up..pull them out and see what condition they are in. Check your MAP as well. And even boost leaks.....it can be a lot of things

 

[JonoTurbo]

I don't recall the exact one but I just used the epoxy they sell at Autozone or wherever, 15k later and it's still holding up. Anything non-conductive that can handle the heat will be fine. Heck I have some of that epoxy sealing the cracks on the fuel pump of my motorcycle, its tough stuff.