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I supported Toymods
Location:
Perth WA
Registered:
May 2002
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1JZ: AF ratios too rich
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Sun, 29 September 2002 11:32
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Hi to all the JZ guys, and asking anyone who knows about Toyota ECU's (OR ANYONE THAT CAN HELP).
I've just got back from entering my car in a dyno tune competition and was mildly disapointed to see that it developed 166RWKw at 0.9 bar boost. I say disapointed because I have previously dynoed at 193RWKw at the same boost on a much warmer day in February. In addition the previous run was with the old stock intercooler, and I'd like to think the new (550X330X75mm)intercooler runs with less restriction. 
The dynos were both Dyno-Dynamics. (193 on Tilbrook's, 166 on Turbo-tune), and boost was stable on both (0.9bar).
The lesser run had AF ratios about 11:1 (166kw)vs 12-12.5:1 (193Kw)
I have not changed anything besides the intercooler, changing my worn out spark plugs (to NGK Iridiums) and tipping in some octane boost / injector cleaner a month ago.
My mods: Boost (0.9bar), 3 inch down pipe back exhaust, Apexi S-AFC (tuning unchanged), intercooler.
What could have changed the air:fuel ratios? Does the ECU "learn" to go back to the factory settings? What does annoy me more is that the before adjusting the AFC the "stock" readings were 0.8 bar + AF ratio 10:1 = 172RWKw!!!!!!!!!!!!! 
Can I try to reset the ECU or should I lean out the AF more with the AFC?
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Location:
Canberra
Registered:
May 2002
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Location:
Sydney
Registered:
May 2002
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Re: 1JZ: AF ratios too rich
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Sun, 29 September 2002 11:50
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Does the car feel the same? Different Dyno do give different readings - Tilbrooks has been described as generous in the past. It dynoed a stock 1J Soarer at 160+ rwkw, whereas most get 130-140rwkw stock.
The ECU learning should not affect the S-AFC at WOT (open loop) when the S-AFC is effective - closed loop is another story as the ECU will adjust based on sensor readings.
With my Soarer, I've never seen any benefits from an ECU reset on the Dyno, only in Day to Day driving in closed loop - I assume the JZA ECU is similar in operation.
What were your AF readings on this last run - similar in shape to the initial setup run or different? The output of the O2 probes wil be different between Dynos as well - I had some difference in AF readings between my normal dyno tuning runs at Croydon and the Dyno Day runs at Premier, but the shape was very similar.
Having said that, the FMIC may have altered your AF settings and a readjustment may be necessary.
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I supported Toymods
Location:
Perth WA
Registered:
May 2002
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Registered:
May 2002
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Re: 1JZ: AF ratios too rich
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Sun, 29 September 2002 21:50
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Don't panic Mel,it could be the difference between dynos.I am concerned about the lack of difference in power after the install of the decent FMI/cooler.My soarer gained heaps of power when i did it.But my time didn't drop,due to excessive wheelspin.I put on sticky tyres and blasted 4.8secs and 12.9 for the 1/4 mile on a G-Tech(previous best 5.2,13.2secs with same sticky tyres).also,terminal spped at the end of the quarter is a very good indicator of power,and my terminal speed increased by 5km/h,showing a good gain.
With regard to air/fuel ratios,I'm not sure i can shed light on what the hang has happened,however i will offer this long shot of a suggestion.Your O2 sensor is faulty,possibly caused by being coated by lead,or the residues often left by octane boosters.The engine reverts to its emergency 'safe' base map for fuel and timing.Power is naturally less.Apparently these can be cleansed by stuffing them into a lemon for a while.Or an electrician can determine if the O2 sensor is sending signals or not.Yeah yeah,I know this is from left field,it might not apply.
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Location:
North Sydney
Registered:
May 2002
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Re: 1JZ: AF ratios too rich
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Mon, 30 September 2002 02:27
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Had you warmed up the car sufficiently before your run? If the coolant temp was reading anything more than 6-8 deg c below normal operating temp the car will automatically run richer as the car is still "warming up". That may have been an issue or not. Also if you were warming it up and maybe to much heat soak could have been an issue. Your intake temp sensor may have hit like 50+ degC while you were idling and this also will make the ecu inturn make the engine run richer.
From my experience about 12.4>12.5 is optimum for turbo cars, well thatS what i run on full sing. The richening early on in your graph will be where your turbo is trying to spool. Extra fuel is added which makes the exhaust gases denser and this makes your exhaust turbine spool up much faster. I've got up to 18% extra fuel to help spool up in part of my mapping curve. That richness isn't anything to worry about, its a good thing. Your full load af ratios are important though.
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Location:
U.S.A
Registered:
July 2002
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Location:
Adelaide
Registered:
August 2002
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Re: 1JZ: AF ratios too rich
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Mon, 30 September 2002 11:35
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hi mel, just dropping in to say congrats on winning the dyno comp  i was the guy in the black audi jacket - my mate matt was talking to you for abit i think...i didn't have my cressy there as it was the mitsubihi dyno day, had to bring the scorp - wish i'd put it on the dyno now, would have beaten ya 
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I supported Toymods
Location:
Perth WA
Registered:
May 2002
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Re: 1JZ: AF ratios too rich
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Mon, 30 September 2002 13:42
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Thanks for the suggestions guys.
As I see it I might persevere and see if I can reproduce a similar time while "performance testing". If my times get close, there probably isn't the indicated 30kw shortfall in power.
I'll get the O2 sensor checked, and I might get the car re dyno tuned before (for a baseline) AND after resetting the ECU by disconnecting the battery.
To be honest, I think the car was a little cold to start with (the dyno guys were mucking around tieing it down expecting a monster reading), but the 3 runs were very consistent.
After a little thinking I'd like to know - do catalytic converters get blocked? For 9 months I've had to drive less than 5kms to work even though I try to give it a bit of a run.
Biggav - I didn't want to mention that my poorly running Supra had won the Mitsu EVO/GSR dyno day! They are great guys with (very fast) nice cars, who had a go, without bitching about anything. Just as well the prize is a $30 voucher off the next Dyno tuning!!
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Location:
North Sydney
Registered:
May 2002
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Re: 1JZ: AF ratios too rich
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Tue, 01 October 2002 09:55
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Yep, cats sure can get blocked, check it out for sure.
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I supported Toymods
Location:
Perth WA
Registered:
May 2002
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Re: 1JZ: AF ratios too rich
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Tue, 01 October 2002 11:13
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What does it feel like if the car is not running on high enough octane fuel? I usually fill up with some sort of 98 octane brew (preferably Mobil Synergy 8000 or BP Ultimate) but the weekend before dyno I filled up from a petrol station I don't normally go to with BP Ultimate. Could it be dodgy fuel, and the knock sensors retading the ignition? Would that make the AF richer?
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Location:
North Sydney
Registered:
May 2002
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Re: 1JZ: AF ratios too rich
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Tue, 01 October 2002 13:12
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You wont feel it through the seat of the pants, that wont be your problem. Most likely the cat, particularly with those rich af ratios. The lesser octane fuel wont have any significant effect on af ratios, anything that's measurable anyway.
Pull the cat out and check it:)
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I supported Toymods
Location:
Perth WA
Registered:
May 2002
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Re: 1JZ: AF ratios too rich
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Thu, 03 October 2002 12:19
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Another thought - what about my fuel cut defender? It is a Greddy model. That would conceivably affect MAP sensor voltage.
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Location:
newcastle
Registered:
June 2002
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Re: 1JZ: AF ratios too rich
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Mon, 07 October 2002 04:19
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a couple of things
1. It IS common with factory ecu's for the mixture to become rich.This is often caused by an EVENT such as detonation repeatably occurring .the knock sensor detects this then dumps in more fuel to try to stop this happenning .Many times i have reset my ECU and had a noticable power increase.
So reset the ecu. Particularly after making a big change like the intercooler The engine characteristics will change quite a bit it is possible that you will notice a difference.Having said that the power figure is a little low average is about 179 RWKW but the mixtures seem about right (for stock) ive seen 5 or so AF runs that look about the same .
i agree with all above the first dyno run was way too hot it all comes down to who is using the dyno on the day .At dyno comps they usually quote HOLD power not PEAK .
2. secondly i had a VERY similar Result recently myself .i have a dyno plus and do power runs and 0-100 etc all the time .
Power dropped,0-100 dropped peak boost was the same . i found that a power steering vacuum hose had come off but because it was before the throttle body idle was not effected .i replaced it and power was restored as was performance a week later same problem so i tightened all my Intercooler hoses .power came back peak boost was the same .
The reason for this the air leak is enough to limit the amount of air getting to the intake but not enough to effect peak boost
The wastegate will still open at the same point of boost .So the turbo's just had to work harder
An aftermarket intercooler should make about 10-5 RWKW .CHECK ALL THOSE HOSES
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Location:
Sydney
Registered:
May 2002
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Re: 1JZ: AF ratios too rich
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Mon, 07 October 2002 12:06
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how do i reset the ecu?????
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Location:
Sydney
Registered:
May 2002
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Re: 1JZ: AF ratios too rich
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Mon, 07 October 2002 12:09
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oh the way i can tell if the fuel is good is to push the engine up close to red line.....if it feels smooth doing it the fuel is good if it feels vibraty... umm back off!!!
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Location:
Wollongong
Registered:
May 2002
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Re: 1JZ: AF ratios too rich
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Mon, 07 October 2002 12:52
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To reset the EFI ECU, pull the EFI fuse and pump the brakes a few times to drain whatever power is left floating in the system (I usually leave the fuse out for 30 mins) then replace the fuse.
Or, specific to a 1JZ-GTE (might work for others, but cannot verify) open the DIAGNOSIS port on the engine. Short terminals Ts and E1 with a paperclip. Start the car, you should see a dot light up next to the clock (on a Soarer digital dash anyway). Turn the car off, remove both terminals from the battery and leave the car overnight with the short in place. Return in the morning, remove the short and re-connect the battery.
(Courtesy of LSOC forums).
I haven't tried the 2nd option yet (not enough time), but the first one does work and I have noticed a difference.
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I supported Toymods
Location:
Perth WA
Registered:
May 2002
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Re: 1JZ: AF ratios too rich
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Fri, 11 October 2002 12:16
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Thanks for your replies guys -
Being the weekend (Friday night) I had a bit of time to do some additional "road testing".
I disconnected the battery for 15 minutes, and waited for the ECU to reset.
Then I made way to a local deserted 110kmh zone to compare 0-100 times. It was an ideal evening - still, cool, dry.
Carefully making sure there were no others at risk, I did a non stalled time - 8.9 seconds (!!!!!!)
The car was running OK, nothing had exploded, it idled OK.
I checked peak boost hold - 0.14 Bar (uh oh!)
Thoughts ran throuh my mind...
Blocked air filter, blocked cat, sensor hose leak? Turbine wheels?
I spent about 15minutes on the way home thinking of how to hide the considerable hole to be caused by a GT30/manifold/wastegate in my bank balance to my wife.......
The car still ran OK, but boost would not run over .1 bar
Giving it the once over at home, I was relieved to find the intercooler-manifold hose had slipped partially off, venting heaps of boost. After tightening it up again I was happy to get 0.9 bar after a short drive.
The moral? Check the hoses! (and the 1jz runs deceptively well without turbos)
I'll let you know how everything goes in the future.
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Location:
Sydney
Registered:
May 2002
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Re: 1JZ: AF ratios too rich
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Fri, 11 October 2002 12:29
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great stuff man good to hear!!!
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Location:
Adelaide
Registered:
August 2002
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Re: 1JZ: AF ratios too rich
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Fri, 11 October 2002 14:52
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have to organize another dyno day now mel
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Location:
Wollongong
Registered:
May 2002
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Re: 1JZ: AF ratios too rich
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Fri, 11 October 2002 16:23
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8.9 seconds for a 2.5L 1JZ without boost is pretty damn quick I reckon.
Still able to beat most other NA cars on the road. Great to hear !
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Location:
newcastle
Registered:
June 2002
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Re: 1JZ: AF ratios too rich
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Sat, 12 October 2002 11:05
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good to hear now dont forget to reset again .Also the top hose is famous for blowing off id invest in some good aftermarket clamps.... fixed all my probs
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