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Discussion Starter #1
Well, I'm new with the AEM but I spent a good deal of time reading up and researching the system. Anyways, what A/F do you guys run on your standalones at idle? It's a bit tough to work use a standalone with the ETCS(drive by wire) throttle body. You kind of have to work with the stock computer to achieve a good idle since the stock ecu is controlling the throttle instead of a IAC driven by the standalone.

I still have a ton of work left to do on my AEM EMS, but so far my idle isn't so legit lol. I got it a little better and I'm able to idle at around 11.5:1 to 12.5:1. Once I go higher than that the car starts to sputter and idle rough. I gapped my plugs pretty close and they might be fouled from running rich from the initial setup and rich ass tune. I have a HKS DLI wired in as well. I'm gonna pull the plugs tomorrow to see how bad they are and maybe increase the gap.

Just wanted to get an idea of how you guys are idling and running on your setups.
 

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What size injectors are you running, and what crank degree are you starting injection at? You should be able to get it to idle in the mid 14's (AFR). Check your injection sync tooth, and injection advance map...




Well, I'm new with the AEM but I spent a good deal of time reading up and researching the system. Anyways, what A/F do you guys run on your standalones at idle? It's a bit tough to work use a standalone with the ETCS(drive by wire) throttle body. You kind of have to work with the stock computer to achieve a good idle since the stock ecu is controlling the throttle instead of a IAC driven by the standalone.

I still have a ton of work left to do on my AEM EMS, but so far my idle isn't so legit lol. I got it a little better and I'm able to idle at around 11.5:1 to 12.5:1. Once I go higher than that the car starts to sputter and idle rough. I gapped my plugs pretty close and they might be fouled from running rich from the initial setup and rich ass tune. I have a HKS DLI wired in as well. I'm gonna pull the plugs tomorrow to see how bad they are and maybe increase the gap.

Just wanted to get an idea of how you guys are idling and running on your setups.
 

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I just went and had my car tuned over the weekend. the tuner had a hard time with idle on the AEM they had to tighten/shorten the throttle cable to make it work. the car still stalls every now and again when its hot. on cold starts the car sounds like its reving too high
 

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I don't have anything authoritative to offer since I don't have a standalone.

But.

I've had a sneaking suspicion for awhile now that the stock ECU/TB, when paired with a standalone tends to close down on the TB too much.

My .001 cent analysis:

1) Your A/F at 14+ has rough idle. 11-12's is better. Combustion wise, makes no sense. This tells me that there is so little air getting through that at 14+, there's very little combustion taking place, cause very little air is getting through. 11-12s, you're combusting almost all the usable air (which is still very little) and idle is better. The AFR tells you oxygen content in the exhaust gas, but not flow, and you need a minimum amount of breathing to get a good idle.

2) The stock TB minimum aperture is calibrated for an open intake. You've now installed a restriction (at idle) in the intake path. The minimum aperture is no longer sufficient and needs to be opened up a bit via the tiny setscrew on the TB.

Couple tests:
1) Try turning the steering wheel when idling...does the idle up (via eTB) help the idle at all?
2) Introduce a small air leak after the TB...does this change the idle?

IMO, spark gap is not the issue at idle if you're running fine at speed. I may be way off base here but let me know.
 

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i idle at around 12:8-13:1

I just went and had my car tuned over the weekend. the tuner had a hard time with idle on the AEM they had to tighten/shorten the throttle cable to make it work. the car still stalls every now and again when its hot. on cold starts the car sounds like its reving too high
im having that same exact problem with cold starts. it jumps all the way to 2500rpm then drops to 1500 when it gets a little bit warmed up.
 

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Discussion Starter #6 (Edited)
Gonna try checking it out again later. I know I've read that people on here say the "optimal" idle with a AEM standalone is 12.5:1. It sucks because it stinks in traffic lol!

I hope it's just some setting in the software that I can correct rather than it being a hardware deficiency of the AEM.

Oh yeah also how many degrees of timing do you guys run at idle/low rpm(less than 1k)? I have a GTE head and internals so it may be a little different from you guys...but still close enough for me to get a rough estimate. I think I'm runnin about 17 degrees or so.

Baadhabit: When your tuner tunes the car. They MUST dial the AEM in to the settings the stock ecu wants to see for the throttle range at idle. I was having some serious issues with the car cutting out and not idling correctly. Just keep adjusting the settings till the factory ecu is happy. Reason for this is because for the throttle by wire setup...the stock ecu is still controlling it.
 

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My car idles, drives and starts like stock. Idle is near stoich with 850CC low impedence injectors with Toyota Drive By Wire.

I use a TEC3 with my own BlackBox to keep it all happy. If I can do it with a TEC3, its much easier to accomplish on a AEM.

Here you go..



 

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That's probably because they have their injector phase tooth set to 12 along with a flat injector advance map.

Gonna try checking it out again later. I know I've read that people on here say the "optimal" idle with a AEM standalone is 12.5:1. It sucks because it stinks in traffic lol!

.
 

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1) Your A/F at 14+ has rough idle. 11-12's is better. Combustion wise, makes no sense. This tells me that there is so little air getting through that at 14+, there's very little combustion taking place, cause very little air is getting through. 11-12s, you're combusting almost all the usable air (which is still very little) and idle is better. The AFR tells you oxygen content in the exhaust gas, but not flow, and you need a minimum amount of breathing to get a good idle.
Wouldn't it mean that he has to much air coming in and not enough fuel if it sputters out at an a/f of 14? If it would work better in a more rich environment like 11 or 12 and not at 14 the difference is more fuel being in the mixture.

let me know if im wrong though but i believe that he is not getting enough fuel which could be the case if he is using big injectors because bigger injectors have problems with putting out small amounts of fuel.
 

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o wow, just looked and noticed 850cc injectors. That could be the reason why its stalling out. A big injector and small amounts of fuel don't mix well, but i could be completly wrong about this.
 

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Discussion Starter #11
Did some more fine tuning today. I have the idle nailed down decently. It stays at around 650-750rpm. I have 1000cc injectors :)

I was looking into the injector advance map, but the AEMPro manual has no mention of it. I had to hop on their forums to see what it does.
 

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Wouldn't it mean that he has to much air coming in and not enough fuel if it sputters out at an a/f of 14? If it would work better in a more rich environment like 11 or 12 and not at 14 the difference is more fuel being in the mixture.

let me know if im wrong though but i believe that he is not getting enough fuel which could be the case if he is using big injectors because bigger injectors have problems with putting out small amounts of fuel.
I think you missed the point he was trying to make. He was talking about air flow, as apposed to A/F ratio. With no way to open the throttle (ala, DBW) or with a bypass valve (ala, IAC motor) than you possibly do not have enough air volume to keep the motor happy at a realistic 14.X ratio. If you increase the air volume, you should be able to tune to stoic as apposed to 12.X or so. TeckIS300, I have wonderd myself if this is what it going on, as I have to idle at 13.X to avoid misfires.

In the TEC3, you have two settings/controls that drastically affect idle quality and A/F. One is called UAP or User adjustable pulse width and the other is POT or Pulse width offset (time). These two controls can be thought of as a course adjustment (UAP) and a curve adjustment to the VE table. If the AEM has similar controls, you might try playing with them to get a better/leaner idle.
 

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Did some more fine tuning today. I have the idle nailed down decently. It stays at around 650-750rpm. I have 1000cc injectors :)

I was looking into the injector advance map, but the AEMPro manual has no mention of it. I had to hop on their forums to see what it does.
so how do you have your inj advance map setup if you dont mind me asking.
 

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Discussion Starter #15
so how do you have your inj advance map setup if you dont mind me asking.
I just copied the injector and ignition advance map off a Supra. Not sure if that was a good idea or not lol...but so far the car is running decently well and idles good. AND...technically I'm running a Supra engine in my setup since I have the GTE bottom end internals and a GTE head. I need to do more reading and researching into what it actually does before I start screwing around with it but for now I'm leaving it as is.
 

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Cool that you got it idling better. Care to mention what did it?

Thanks for the clarification htekwo....yes that was the point I was trying to make. Another indication to my theory is the seemingly high timing advance for idle at 700ish rpm. Where stock runs 10-12*ish, you're doing 17? Just seems like there is not enough airflow to support proper combustion at idle.
 

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I just went and had my car tuned over the weekend. the tuner had a hard time with idle on the AEM they had to tighten/shorten the throttle cable to make it work. the car still stalls every now and again when its hot. on cold starts the car sounds like its reving too high
i hate to thread jack but does anyone have any ideas on this?
 
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