1jz-gte major power taper beyond 5000rpm

[SL666]

usually if its been pinging it should pull a code? (if its pinging enough to retard the timing to the level its killing the fun) i'd suggest its something else.. someone else was having simular issues with a 1j, but i can't remember who..

[urantia]

really? well thats somethign i didn't know, so it really should of set of a code if it were pinging and the ECU had to pull back the timing a heap. Becuase the power difference is quite substantial. When i first had the 1jz running it was so much more powerful, enuf to spin the tyres while doing 100km/h (4th gear downshit to 3rd = wheels would spin up easily) Now it feels about half as powerful.

hmm ok the plot totally thickens. I should check for codes, but i know i wired in the cel correctly last time it was complained about no speed signal which i've now wired in and haven't had the engine light flash since, so this is starting to sound like a fundamental problem that the ECU isn't aware of.

[urantia]

thought i should update anyone that is interested.

Yay for 98 octane BP fuel bieng finally availiable in tassie!

but bugger it didn;t restore my lost power.

Seemed strange that when i stomped it in 3rd gear the tacho gets to 5,000rpm and pretty much stays there or very very very slowly winds out. hard to know if this is how jza70's perform stock??

The next thing: see what my boost is doing, so whent to supercheap for a boost guage, none in stock, try repco cheapest one hundred and fifty five fuckin dollars for a auto meter or whatever they are called.

It's all getto rigged up for the test tommorow morning on the way to work. So will update with that result when i get to work.

Tried to get some new NGK spark plugs too, supercrap didn't have any. (even the NGK part listing book didn't mention 1jz-gte even tho they had a section for toyota japanese imports) repco were willing to sell me iridium ngk's for $19ea...no thanx. standard NGK plugs for me.

[urantia]

Boost guage tells me my boost is perfect spooling up 10psi and staying there rock solid.
Farkin $155 for a boost guage only to confirm nothing is wrong in that area.

*scratches head*, where the hell has my power gone then? i'm going nuts here.
if only there was a dyno around here!

[SL666]

but at least you can look fulleee sik now.. i had to put in a e-boost to find out that my boost gauge was lying to me and i couldn't really wind up the boost

if boost is stable, it leaves timing and fuel... ('only')

got a timing light? probably wont show anything free-reving though (because its not under load) but it might be nice to check the base settings.. (in case the CAS has moved or somethign)

Your check-engine light works etc?

[urantia]

Just reading over this thread again and the replies i got i'm starting think i must be imagining things and my 1jz is fine and i'm under the illusion it had more power when i first got it going.

Last thing for me to check are the coils and spark plugs and if no change i'm gonna leave it at that. At least until i can get my car to a dyno.

[urantia]

but at least you can look fulleee sik now.. i had to put in a e-boost to find out that my boost gauge was lying to me and i couldn't really wind up the boost

if boost is stable, it leaves timing and fuel... ('only')

got a timing light? probably wont show anything free-reving though (because its not under load) but it might be nice to check the base settings.. (in case the CAS has moved or somethign)

Your check-engine light works etc?

Sorry just saw your reply after i posted. Yep my check engine light works, have had a few ECU codes after i completed the conversion just simple ones like no SPD etc (which i've wired up now)

I do have a timing light, but i don't know how to adapt it to work on a coil on spark plug type setup. (ie where can i clip my timing light pickup?)

[poombah]

My brothers soarer pulls hard all the way to the limiter.

it dies off a bit but yeah mine creeps to ~7400 really really quickly...haha

the ecu will retard timing on lower ron fuel (ie 95 ron).. maybe thats what you're experiencing?

[wiso]

I do have a timing light, but i don't know how to adapt it to work on a coil on spark plug type setup. (ie where can i clip my timing light pickup?)

that is a really good question, does anybody know how to check the timing on a coil on plug?, do you need a special timing light? any advise would be good, as i may need to do this also after doing my timing belt, just to be sure

[urantia]

Yeah i did hear something on how to do this, i think Chris Davey had a method or it may of been Norbie on how to use a regular inductor pickup type timing light with these coil on spark plug motors.

Something along the lines of getting a normal high tension lead and connecting it to number 1 coil (connection how??) and hooking the timing light onto that. But that's about as best my memory streches with that. Thought i would ask anyway so someone could tell me again

[urantia]

it dies off a bit but yeah mine creeps to ~7400 really really quickly...haha

the ecu will retard timing on lower ron fuel (ie 95 ron).. maybe thats what you're experiencing?

poombah yours shoots up to 7400rpm? dam! it's worked abit then?

Yeah i thought my ecu was pulling timing on 95 ron too, but now we have 98 BP and it didn't make a difference maybe a slight improvement in overall power but nothing like i was expecting.

[Endless]

I do have a timing light, but i don't know how to adapt it to work on a coil on spark plug type setup. (ie where can i clip my timing light pickup?)

Towards bottom of the page here in Chris' thread.

http://www.toymods.net/forums/showth...p?t=932&page=5

[SL666]

might be worth (if you haven't done it already) filling up with 98, and disconnecting the battery overnight (or for a while) so the ecu fully resets, then re-connect warm it up and flog it and see if it still has the issue (at least that will in theory get rid of the ECU retarding timing on purpose issue)

[urantia]

Sweetness thanx for that find Endless will check that tonight and confirm timing is correct. (do 1jz's have like a cam position sensor to change the timing if it's out? ala 7m-gte style?)

SL666, i will try this too, i've used the pull fuse method for 60 seconds to reset the ECU. Perhaps this isn't long enuf to fully drain all residual power from the ECU to reset? Will report back on my findings with this method.

[chris davey]

I got a normal lead, chopped the end off and stuck it in the coil. Connect the other end to the plug as normal.

After doing this, 1jz747 informed me that I didn't have to chop the lead and you can just take the blue section off the coil and the lead should plug straight onto it

I took a pic somewhere but I have no idea where it is now