Breaking up around 3000rpm

[Satan]

Replaced coilpacks w/spare 1JZ ones, new plugs, and Fed with the ISC some more... Still sputtering and loping idle (ISC). Died on me about half-mile from home and tripped a water temp sensor code (wouldn't start). Swapped with my other ECU that I still had in the car, still code 22 and no start.

Wife and son came out and brought another ECU (rcvd in mail today) and started right up. Still some sputtering, lopy idle, but no codes. SOB!!!!

I need to get to the poly bushings this weekend, but we really need to figure out the source of this mess.

Jon,
Who did your wiring, or what map did you use? The one I posted a few months back in the wiring peer review (please say yes)? Maybe we have a wire/connection out of whack...

 

[YotaRob]

It may be a PITA but you might just go ahead and get the ecu pinouts and start ohm'ing out the wires to see if something doesn't match.

 

[GotTurbos?]

Replaced coilpacks w/spare 1JZ ones, new plugs, and Fed with the ISC some more... Still sputtering and loping idle (ISC). Died on me about half-mile from home and tripped a water temp sensor code (wouldn't start). Swapped with my other ECU that I still had in the car, still code 22 and no start.

Wife and son came out and brought another ECU (rcvd in mail today) and started right up. Still some sputtering, lopy idle, but no codes. SOB!!!!

I need to get to the poly bushings this weekend, but we really need to figure out the source of this mess.

Jon,
Who did your wiring, or what map did you use? The one I posted a few months back in the wiring peer review (please say yes)? Maybe we have a wire/connection out of whack...

I did all of my wiring myself (with some guidance and supervision from Dat) per this website:

http://web.archive.org/web/20051227115906/www.1jz-gte.us/index.html

Wiring on this page: http://web.archive.org/web/20051227112114/www.1jz-gte.us/92Supra6.html

By map to you mean sensor or tune? I'm on a 2jz map sensor with an incomplete tune right now through an SAFC NEO.

Let me know if you need spares of anything to try out. I should either have a spare handy or I'll just drive over there and we can swap it off of my car.

Jon

 

[grimreaper]

seems like you guys are past the coil pack issue, but if needed i have a set that work on my floor, and then a brand new set on the car ( if for some odd reason) is needed to try out. mine are stock 7m's though if it matters,

 

[Satan]

...Sorry. Map, meaning wiring plan/mapping from the MKIII body to the 2J engine harness, and other misc. connections.

I'll have to get back at it soon, but have other stuff I need to get done (suspension, A/C, etc)... Which at this point, is better return (ROI) on investment of my time than chasing ghosts.

 

[sctwinturbo]

well i did what you did with the fuel pressure and it ran like crap
but at the shop were i was at when i ajusted it the guy told me i had to take the vacum hose off and then change it
so i tried that and dam it ran great smooth all the way up

 

[Satan]

Which vacuum hose?

Getting ready to get the wife's engine ordered, so will have some spare parts to mess with as well. Would rather isolate it, since it seems to be fairly common, which means it's some small/slight difference that has caught us all.

Did ya'll unravel your harnesses and remove extraneous wiring/connectors?

 

[Andre]

obd1 lean spot maybe?

obd1 2jz ecus run mid 14 a/f till ~4k then switch to an open loop mode. Maybe your low rpm closed loop tune is sooooo far out that the ecu is running an extreme negative fuel trim trying to get the tune correct then in that range, its tooo lean and misses?

Yep thats is exactly what my car did when i had that lean spot problem

 

[Satan]

Judging by my plugs/exhaust, it's too rich. :dunno:

 

[YotaRob]

could be rich a lil and between shifts untill it goes open loop

 

[GotTurbos?]

He is talking about the vacuum hose on the Fuel pressure regulator. You have to adjust it with the vacuum off, then attach the vacuum when you're finished. That's the way I did it. The car has a nasty misfire sometimes when cruising in 5th, even with the wideband reading 14.5 it just feels like I'm completely losing fuel for a second then its coming back on fast enough for the wideband not to jump. It is running great at high throttle though. Weird.

 

[91T breezen']

I had my car tuned Friday, and now it's doing it again. However, it runs considerably better through all the rpm range than it did before, save for right around 3000rpm. He tuned with my Profec B II at 1bar, and pulled out 18% fuel at the top with the SAFC II. Car pulls very hard now all the way to 7000rpm, and layed down 275whp, and 256tq with a stock cat bolted back on! Hp jumped to 280, without the cat, but the tq fell off a little though (10ft lbs) Graph is beautiful with a/f at 11.6-12, all the way from 3000-7000rpm, almost looks like a V-8 car with tq and hp almost dead even, all the way through! If I could just get rid of the 3000 rpm gremlin, it would be great!!!

 

[Satan]

He is talking about the vacuum hose on the Fuel pressure regulator. You have to adjust it with the vacuum off, then attach the vacuum when you're finished. That's the way I did it. The car has a nasty misfire sometimes when cruising in 5th, even with the wideband reading 14.5 it just feels like I'm completely losing fuel for a second then its coming back on fast enough for the wideband not to jump. It is running great at high throttle though. Weird.

Any new progress? I am going to try and put some time into mine this weekend. can you tell me all the components you swapped, when troubleshooting? Instead of repeating that, maybe I can try some of the stuff that you may not have gotten to or tried yet.

I don't have any way to adjust my fuel pressure. Though since it's running rich, I am not sure I want to play with that piece unless I really have to.

E

 

[sctwinturbo]

did you change the fuel pump ? yet
and you are not running a fuel pressure reg. ?

 

[YotaRob]

I just thought of something, IIRC your are running with an Aristo ecu no? which I think are equipped with 440 cc inj. and you installed larger? Do you have a SAFC? If so, your ecu is running closed loop up until it starts breaking up when open loop occurs, which in closed loop the ecu is always checking fuel trim and adjusting it and can compensate for larger amounts of fuel. Open loop just goes back to base fuel map and ignores the o2 sensor feedback. Might need to get to playing with the SAFC to control the open loop mode as it is all out of wack with any larger amount of fuel.

If this is all jarbled sorry, @work right now.

Robert

 

[GotTurbos?]

Are we talking about me or Elvis now? My problem was fixed due to two things... The non blown ECU, and playing with my SAFC Neo a little. I had to adjust the RPM adjustments to where I was adding fuel at 2700 and 3000 but not before hand, I have it pretty smooth right now.

 

[sctwinturbo]

satan says he has not way to adjust fuel pressure

 

[GotTurbos?]

Elvis do you have a wideband? That is one of the very first things I bought for this car and would probably be lost without it. I have a fuel pressure regulator... but I have it set to stock pressure, so that shouldn't be much of an issue for you. I would see if we can figure out if there is away to adjust for your problem with an SAFC or similar controller before you start swapping everything (like I did with every sensor in the car before I figured out I just had a blown ECU).

 

[grimreaper]

a multimeter would solve alot of the swap n see not to mention save a few bucks as well..

granted not everything is as cut and dry as hooking a multimeter up to it, but most of the sensors should check out easily enough.

 

[YotaRob]

Are we talking about me or Elvis now? My problem was fixed due to two things... The non blown ECU, and playing with my SAFC Neo a little. I had to adjust the RPM adjustments to where I was adding fuel at 2700 and 3000 but not before hand, I have it pretty smooth right now.

Thats what I was thinking Elvis needs to do. He has tried several ecu's though hasn't he?