1JZ Single SC400 bucking and irregular idle
#17
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whats your car idling at and have you connected the laptop at all?
that video can help and with weather changes it is not uncommon to have to tweak the idle map.
what you want to look at is the idle target, the idle learned value, and then your idle max and minimum.
If the idle learned is positive and at the max number and you still aren't at the target idle rpm's, then the idle map will need to be adjusted up or the max increased so it can get to its idle target.
the default is for the aem to pull and or put in up to 20 degrees of timing when it cannot hit the correct idle rpm.
If you have ever had the aem doing this 40 degree timing swing on you, you would find your wideband doing exactly what you are describing, but there are a dozen other things it could be to make the wideband do that but with shutting off on you with accessories on I can tell your probably idling too low and your a/c parameters need some tweaking.
I have never heard of knock sensors being off either, they are not supossed to be the same for every engine.
the proper procedure is to load the engine up through all the ranges without boost, record the values from the knock sensors to use as a baseline, and then to tune based off of the difference when you add boost. If you do not do that you are just going off of some hypothetical knock values, and the ones in the basemap are conservative so they register "knock" faster.
that video can help and with weather changes it is not uncommon to have to tweak the idle map.
what you want to look at is the idle target, the idle learned value, and then your idle max and minimum.
If the idle learned is positive and at the max number and you still aren't at the target idle rpm's, then the idle map will need to be adjusted up or the max increased so it can get to its idle target.
the default is for the aem to pull and or put in up to 20 degrees of timing when it cannot hit the correct idle rpm.
If you have ever had the aem doing this 40 degree timing swing on you, you would find your wideband doing exactly what you are describing, but there are a dozen other things it could be to make the wideband do that but with shutting off on you with accessories on I can tell your probably idling too low and your a/c parameters need some tweaking.
I have never heard of knock sensors being off either, they are not supossed to be the same for every engine.
the proper procedure is to load the engine up through all the ranges without boost, record the values from the knock sensors to use as a baseline, and then to tune based off of the difference when you add boost. If you do not do that you are just going off of some hypothetical knock values, and the ones in the basemap are conservative so they register "knock" faster.
#18
1JZ Single SC400
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Thanks Ali. To answer your question, I havent connected anything yet. I have been at work since I posted or started this thread. I am going to look at this tomorrow and the rest of the week. I also contacted another friend of mine who worked for Lexus in Nashville. He is very smart when it comes to tuning and figuring out the little things that seems to stun the others. He is supposed to be coming over and looking over a few things. He seems to think it is the TPS going bad causing the bucking and surging, with the help of the IACV. He said they really depend on each other, and when they cant connect together, they try to compensate, possibly causing the issues I have having. He started a new job, and he is not sure on what day he will come over, but he said he will.
I appreciate all the great information on this. You guys are the people I trust. Keep the feedback coming.
I appreciate all the great information on this. You guys are the people I trust. Keep the feedback coming.
#20
1JZ Single SC400
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Thats correct Omar. No knock sensors. This was confirmed by another tuner I spoke to over the phone. He told me they generally turn these off when using a single turbo and not using the stock ecu. How do you send this file to you? I understand by email but how by using the AEM? Not real sure how to do that?????
Can you tell me how?
Can you tell me how?
#22
1JZ Single SC400
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They were originally on. While tuning the car the tuner claimed the car was losing power. They turned them off. I have never turned them back on. I havent touched the AEM since then.
With everyone having mixed opinions on this, can you explain why you would turn them back on with my setup? Thanks Ali SC3.
With everyone having mixed opinions on this, can you explain why you would turn them back on with my setup? Thanks Ali SC3.
#24
1JZ Single SC400
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This is why I love the forums. I have learned so much from this build. Now I need to search on AEM website to learn more about what is in my car and the functions of it. It sounds like I need to take it to the local tuner that I don't trust. My friend Tim should be able to tweak and review the current settings and maps, while I watch ever so closely. I have watched the AEM youtube video like twenty times and made many notes.
If indeed the knock sensors are turned off or bad and in need of replacing, are the 2JZGE sensors the same or has to be one of the GTE's?
Adam, can I call you or call me? 205-482-5533
If indeed the knock sensors are turned off or bad and in need of replacing, are the 2JZGE sensors the same or has to be one of the GTE's?
Adam, can I call you or call me? 205-482-5533
#25
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they just need to be calibrated most likely in the tune if the defaults aren't close. Since you have an ems, you can monitor the knock parameter and if its registering knock with the engine off then they would be bad, but that would be highly unusual. if they are registering higher than normal values, thats actually normal and the defualt is to pull more timing to be safe, but instead of turning it off if it was tuned from a baseline run with knock safe timing, the ems would know that you are not really knocking and it wont pull power. the advantage is that when you actually knock off the charts it will save your motor instead of chugging along.
#27
1JZ Single SC400
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The car seemed to me that it was right. I didnt have anything to compare it to while running an AEM. I have always thought the wideband was off while lightly on the throttle. It has always seemed to bounce around here recently more and more, along with the other symptoms now of jerking/surging, while light on the gas pedal. In all honesty and if my memory serves me right, it has never ran at idle like I thought it should. Another point the tuner brought up was that he had a tough time to set those injectors. I do know they are the largest that will fit in the stock rail for JZ motor, 800 high impedance. I actually went outside to wash the bugs off the front from my road trip and even now at dead cold starting is starting to idle crazy and higher than higher. It almost sounded like it wanted to die, and was stumbling for the first 20 seconds or so, then the idle went alot higher than normal, close to 1300. I have something going on, and wish I had one of you closer to me to educate me in the land of AEM. I would be willing to even pull the check book out, just because thats the way I roll.
#28
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My opinion
You just need a better Tuner, and a new Tune .
I told you that before, the guy who tuned your car will not touch my lawnmower seriously.
Log a couple runs and email them to me omar5989@yahoo.com
IIrc think you press F6 to start to record and F6 to stop the recording, save it and then send it to me.
You just need a better Tuner, and a new Tune .
I told you that before, the guy who tuned your car will not touch my lawnmower seriously.
Log a couple runs and email them to me omar5989@yahoo.com
IIrc think you press F6 to start to record and F6 to stop the recording, save it and then send it to me.
#29
1JZ Single SC400
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My opinion
You just need a better Tuner, and a new Tune .
I told you that before, the guy who tuned your car will not touch my lawnmower seriously.
Log a couple runs and email them to me omar5989@yahoo.com
IIrc think you press F6 to start to record and F6 to stop the recording, save it and then send it to me.
You just need a better Tuner, and a new Tune .
I told you that before, the guy who tuned your car will not touch my lawnmower seriously.
Log a couple runs and email them to me omar5989@yahoo.com
IIrc think you press F6 to start to record and F6 to stop the recording, save it and then send it to me.
#30
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yeah I agree, those all sound like typical excuses for a not so good tune.
to me it sounds like some very simple stuff is off like the idle map, decel fuel cut probably not set low enough (which causes the rev up and down problem), and knock should be tuned.
EMS only runs as good as someone tunes it, and even then it can change with the weather because your tuner only gets it for a few days, but we drive our cars around year round.
to me it sounds like some very simple stuff is off like the idle map, decel fuel cut probably not set low enough (which causes the rev up and down problem), and knock should be tuned.
EMS only runs as good as someone tunes it, and even then it can change with the weather because your tuner only gets it for a few days, but we drive our cars around year round.