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| Stumble Off Idle When Cold, Flat Spot | |
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| Tweet Topic Started: Jul 27 2009, 12:33 AM (1,704 Views) | |
| Leiden | Jul 27 2009, 12:33 AM Post #1 |
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NZ, Whangarei
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Hi, Just looking for a few suggestions as to what my problem could be, my vehicle is a Altezza RS200 3SGE+T Basically on cold start the car will stumble with blips of the throttle, once it warm's up things are fine. I've also noticed that when accelerating from about 1000rpm's to about 2500rpm's in higher gears the car will bog. For instance if I only accelerate with say 50% throttle it seems to have more power than if I accelerate with 100% throttle. All I can think of is that it must be running lean in open loop. When its cold and the O2 sensor hasn't come online it runs open loop and when accelerating at WOT it runs open loop. This would explain why it doesn't stumble when warm and accelerates better with part throttle than WOT (since the ECU has adjusted the mixture via the O2 sensor) Just wondering what could possible cause this scenario? On boost it runs perfect, so I'm confused. |
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| HOT2XS | Jul 27 2009, 08:07 AM Post #2 |
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Body-Kitted
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Completely different car, but my old AE111 20-valve Levin did something fairly similar to this. Also realize the turbo difference here. But as soon as I told Toyota what the car was doing, one of their head mechanics new straight away what it was. He suggested cleaning out the throttle-body and adjusting the butterflies. Not even sure if our cars even have butterflies :rolleyes: But it worked sweet as. Flat spot gone. Worth a shot anyway
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| Leiden | Jul 27 2009, 09:27 AM Post #3 |
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NZ, Whangarei
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Yea I've heard alot of those stories about 20V 4AGE's Those motors have ITB's so thats what he's probably referring to, in my case its just the one throttle plate I have the following guesstimates as to what it could be, BOV - opening on cold idle higher vac TPS - dead spot so no accel enrichment at a certain point Knock - phantom knock pulling all timing (sluggish performance) Water Temp - poor resolution so its not adding enough fuel on cold start |
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| Soiled Altezza | Jul 27 2009, 10:09 AM Post #4 |
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I had this with my e-manage, was due to the way the e-manage was tuned/works. Doesn't have a cold/warm feature just has a one map fits all way of doing things. Since going to the PowerFC runs smooth cold or warm. So what I'm saying is if you've always had this since you've gone turbo I think you have the same problem my e-manage had which is nothing to worry about just drive it as nicely as you can while it's cold. If it's a new problem I'd start looking into the bov etc. |
![]() Garage: http://altezza.dualzdesigns.com/viewcar.ph...wner=17&frmpg=0 | |
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| Leiden | Jul 27 2009, 11:37 AM Post #5 |
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NZ, Whangarei
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Its a new problem, been playing around with the TPS settings to try and eliminate that as a problem. I found that the ECU learns to base TPS voltage so any adjustments you make to it are tuned out so you have to make an adjustment, then reset the ecu and measure again. Pain in the ass lol @Soiled Altezza: Is there anyway your AVC-R can show actual TPS voltage rather than the min/max setting? I need to know the base TPS voltage, which needs to be measured with the Key ON and the ETCS Fuse Removed. That way the throttle plate is sitting at its base setting without any ecu adjustment to the position (removing the ETCS fuse disables the electronic throttle control) Right now I'm sitting at a base voltage of 0.78V with the Fuse Removed. Do you think you could measure yours and let me know? |
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| Soiled Altezza | Jul 27 2009, 03:31 PM Post #6 |
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It just shows real time voltage on it. I'll pull the fuse out at some point and check it for you. Where abouts is the fuse? |
![]() Garage: http://altezza.dualzdesigns.com/viewcar.ph...wner=17&frmpg=0 | |
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| Leiden | Jul 27 2009, 03:55 PM Post #7 |
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NZ, Whangarei
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Its in the engine bay near the battery in that little box, Its a 15A Fuse right next to a 7.5A one, should say ETCS on the lid of the box, if you could that would be awesome! |
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| Soiled Altezza | Jul 27 2009, 04:35 PM Post #8 |
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0.009/0.014V at 0% throttle. |
![]() Garage: http://altezza.dualzdesigns.com/viewcar.ph...wner=17&frmpg=0 | |
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| Leiden | Jul 27 2009, 06:06 PM Post #9 |
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NZ, Whangarei
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That doesn't look right Should be in the range of about 0.5v to about 1.0v, my one's currently at 0.78v with IGN ON & ETCS Fuse pulled |
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| Soiled Altezza | Jul 27 2009, 06:21 PM Post #10 |
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Might have to actually measure it instead of just using the ACV-R... or maybe I didn't have the key 'ON' enough
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![]() Garage: http://altezza.dualzdesigns.com/viewcar.ph...wner=17&frmpg=0 | |
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| yojimbo | Jul 27 2009, 06:49 PM Post #11 |
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Hidden Dragon
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Most TPS will read between 0 and 5v. |
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Toyota Nats 5 x Top Toyota Toymods Dyno Day 19 - Killerwatt King Supra Dyno Day 2015 Outright HP and Torque 11.10@141.34mph (0-400m) 22.048@164mph (0-1000m) Built by ... JMR Race Engineering - Toyota Specialist | |
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| Leiden | Jul 28 2009, 01:53 AM Post #12 |
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NZ, Whangarei
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Ok guys I'm starting to think it might be my FPR thats at fault, I havn't tested the fuel pressure yet but I've added 16.5% extra fuel globally over the entire fuel map and its running alot better than before... |
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| Soiled Altezza | Jul 28 2009, 03:36 PM Post #13 |
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Okaaay, I've finally done it with the key actually on this time and I got 0.88V @ 0%Throttle and 2.6V @ 100% Throttle. |
![]() Garage: http://altezza.dualzdesigns.com/viewcar.ph...wner=17&frmpg=0 | |
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| Leiden | Jul 28 2009, 09:01 PM Post #14 |
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NZ, Whangarei
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Cheers thanks for that, Will set mine tomorrow and see how it goes your 100% throttle settings is only low because the electronic throttle motor usually does the work up to about 75% throttle then it mechanically takes over
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| Bry | May 14 2012, 06:22 PM Post #15 |
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Body-Kitted
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Sorry to revive old thread - but did you ever resolve this issue? I think I may have a similar situation, but I'm not sure if it's just the nature of the engine as I've never driven one N/A! Mines bogs down at low rpm (under 2k) if I'm not in the right gear. |
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| Tezz-Winnie | May 14 2012, 06:44 PM Post #16 |
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Unregistered
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Completely normal for the Beams mate. Mine Labours really hard cruising in 6th at 60Km but in the IS200 with the same ratio diff the 1G is happy to cruise around in 6th at 60km. |
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| Bry | May 14 2012, 06:46 PM Post #17 |
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Body-Kitted
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Yeh I thought this may be the case, I've learnt to drive around it.. you really need to think about gear selection otherwise you go nowhere! I don't bother with 6th under 70km. PS. Are you at work? If so you must do as little work as I do
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| Tezz-Winnie | May 14 2012, 07:00 PM Post #18 |
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Unregistered
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Haha maybe Yea I dont bother with 6th under 80Km lol if im holding 70 ill go into 6th but if the limit changes to 80 ill drop a gear, its annoying but thats what you get with a high strung NA engine. Must be a pain in the arse with the turbo lag lol
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| Bry | May 14 2012, 07:12 PM Post #19 |
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Body-Kitted
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What lag? It very linear power delivery, still running 11.5:1
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| Tezz-Winnie | May 14 2012, 08:07 PM Post #20 |
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Unregistered
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Haha yea I know but you don't get the same low end torque as a na.. Not long now till I go turbo. Just need to wait till rego mount inter cooler and instal turbo then engineer. The list is getting smaller |
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