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Discussion Starter · #1 ·
Well I recently boosted the IS, and I'm running on the map-ecu. Besides being alittle rich, runs fairly well. The problem is shifting. 1st I'll let you all know the basics. The rear 02 has nothing on it. The IAT from the map-ecu is not hooked up.(will be soon) No factory maf is on the car. I do have 2 of the 2.2k res. on the maf. What the deal is shifting. When driving around normal it seems to do its thing, no problems. Now when I go into boost or even just alittle gas, it has trouble down shifting and then up shifting. When it does down shift, and I let go of the gas, it wants to stay in that gear. But after 30+sec it will upshift. I'm thinking the TPS sensor has gone bad. Never had any problems with the tranny before. Just now. I got the VB upgrade done months ago(8+ months).
What are the procedures to check to see whats going on?
 

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Discussion Starter · #3 ·
Auto tranny ecu functions need a maf installed in the charge pipe. Works well.
So your saying hook up the maf and all will be well? What about the tps sensor.
 

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So your saying hook up the maf and all will be well? What about the tps sensor.
Correct the stock auto takes reading off of the MAF for shift points also. Plug the MAF back in and you will notice a difference.

Do you have any valvebody upgrades? You might be experiencing "shift lag" due to boost.
 

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Discussion Starter · #5 ·
The OBDII scanner put up TPS code. Now I have to give 85% gas to do anything. Going to limp mode I think. I've disconnected the bat. to reset the ECU, but with no luck. The car did fine a few days ago(no maf) Could some of the sensors on the throttle body area be causeing this? Theres a TPS sensor, acc. position sensor and a throttle controll motor.

Yes I got the VB done long ago.
 

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You have a very important stock ECU input sensor disconnect, you are going to run into limp mode. Reconnect that and see what happens from there.

You really can't compare your tranny response to before and now as you entire motor and ecu setup is different.
 

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Discussion Starter · #7 ·
I'll see if I can get it mounted. I don't have the mounting flange, nor do I want to spend 200+ for an intake to only use the one peice.
 

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I'll see if I can get it mounted. I don't have the mounting flange, nor do I want to spend 200+ for an intake to only use the one peice.
You can get a maf sensor flange from ATPturbo.com I believe. Buy it cut your current pipe for it and get it welded.
 

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Discussion Starter · #9 ·
The MAP-ECU Green wire provides a signal that replaces the MAF so as far as the OEM ECU is concerned, there is a MAF. It just happens to be generated by the MAP-ECU.
This is what I found out. I press the throttle all the way(WOT), and the "circle thing" inside my throttle body is only opening alittle. At 85% throttle I can get the car to at least idle. So I have come to the conclusion that the problem is in my entire throttle body. Sensor or gears inside have come off/loose, something has gone wrong in there. I'm just going to get a new one. Do you think that if the TPS or something in the throttle body area has gone wrong, that it would tell the ECU/tranny to not shift? If the "circle thing" isn't opening up all the way and the TPS sensor see's that.....then.....it won't shift. Right?
 

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If your butterfly isn't opening up to let air in how is your car moving? I also understand that you're getting a stimulated MAF signal to the stock ecu but it is what it is, stimulated signal. The ECU needs actual and accurate MAF reading.

The throttle body is drive by wire, which means the cable to that foot lever isn't going to do anything. You can stomp on that pedal with all you get it will not open the butterfly. Drive by wire = electronically controlled butterfly plate not a mechanical plate. You can't rule out a bad throttle body just yet. You have no MAF, which means the stock ECU have no idea how much air is going through. It's most likely running in LIMP Mode. Really, start of with the MAF.

Just try it out but cutting the plastic tube on your stock intake pipe and temporarily place it to your intake side.
 

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Discussion Starter · #11 ·
Well I don't have the stock intake. I found something else out. The throttle controll motor is suppose to make a whining sound after you hit the gas. (car on but not started) Well after checking my friends IS, his does it and mine does not. So I know that is bad. If it dont work, then that would explain why when I press the gas alittle, NO fuel is going in. 85+% I get some gas and the car rev's up. I doubt its the maf cause it shifts fine under normal conditions and even alittle boost. The only thing the car doesn't see is the IAT, which I have one that map-ecu gave me but haven't got it in yet.
 

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So you're telling me that inorder for you car to drive you're constantly having the foot pedal 85% throttled? You're confusing me man.

MAF = input sensor.
Your TB = output sensor.

When you get no input, you get no output. If you have a known good part why not just try the known good part and see if it works rather then buy a new one.

You get new fuel because you have no air. You need to explain a little bid more about your setup and your problem. You intitially started the thread with a shifting problem then to me it seems like you have other issues as well. You said that the motor idles only at 85% throttle, if this is the case you have other issues.

Regardless, you have an auto, YOU NEED THE MAF. I am just taking you through steps where you don't have to possible waste your money. I know if you buy a new TB the dealer won't take it back since it is special order and electronic.

Here is what I see. You have components, sensors, ecu, etc. that aren't even completely assembled. My best guess is those are your problems. Completely assemble the setup and see what you get. IAT is also an input sensor, you dont have a MAF or IAT sensor plugged in for the stock ECU, how do you expect the car to react? The MAP ECU is a piggyback, therefore it doesn't control everything, which means you need help from the stock ecu.
 

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Discussion Starter · #13 ·
So you're telling me that inorder for you car to drive you're constantly having the foot pedal 85% throttled? You're confusing me man.

MAF = input sensor.
Your TB = output sensor.

When you get no input, you get no output. If you have a known good part why not just try the known good part and see if it works rather then buy a new one.

You get new fuel because you have no air. You need to explain a little bid more about your setup and your problem. You intitially started the thread with a shifting problem then to me it seems like you have other issues as well. You said that the motor idles only at 85% throttle, if this is the case you have other issues.

Regardless, you have an auto, YOU NEED THE MAF. I am just taking you through steps where you don't have to possible waste your money. I know if you buy a new TB the dealer won't take it back since it is special order and electronic.

Here is what I see. You have components, sensors, ecu, etc. that aren't even completely assembled. My best guess is those are your problems. Completely assemble the setup and see what you get. IAT is also an input sensor, you dont have a MAF or IAT sensor plugged in for the stock ECU, how do you expect the car to react? The MAP ECU is a piggyback, therefore it doesn't control everything, which means you need help from the stock ecu.
Yes inorder to see fuel I give it 85+% throttle. Ok lets try this. Go to your IS, turn the key to the on pos. hit the gas to WOT and then let go. Go to the TB a listen for the whinning sound. That sound is from the Throttle Control Motor. Mine has no sound. So if the TCM is bad then it won't send a signal to the TPS which won't send a signal to the ecu to tell the tranny to shift. The maf is getting a signal though the map-ecu, other wise my car won't start. Here is what map-ecu tec. help said:
Small problems....little help with IS300 - MAP-ECU Forum
I'm still going to install the fac. maf. Try to at least. But the TCM is bad, I have no whinning sound.
 

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Discussion Starter · #14 ·
Also the map-ecu turns the car from MAF too MAP. If the car blows a boot I'll still keep running, just without boost. If I was maf still and blow at boot, I die right there, cause with a air leak the maf will not see air therfore not allow my car to remain running.
 

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You're jumping all over the place with your diagnosis. You went from TPS to TCM in a matter of minutes. Take a look at the repair manual, there are steps in there to test out sensors; both input and output.

Unfortunately, my IS is under the knife right now. But I am well aware of the noise from the TB, it's a motor that controls the butterfly plate.

A TPS does not get a signal to it, a TPS is an output sensor it sends out signal does not recieve signals. Obviously these component worked fine before you did the turbo install, it's unusual that they will go mysteriously bad. You need to install everything before even going any further. You're in a big mess, honestly, completely install all of you components. You're jumping all over the place.

A car will start without a MAF, even if it didn't have a stimulated signal .
 

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Discussion Starter · #16 ·
The noise controll's the butterfly plate. Right! See now mine is broke, so thats why I have to press the gas so much, to manually give it gas.
 

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Discussion Starter · #17 ·
I will take pics.....wait 15min
 

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Discussion Starter · #18 ·
This was done thursday




2.2kohm res. X2
 

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your in limp mode, plate will never move unless you stomp the peddle to the ground in limp mode. Seems like you are new to the limp mode. Maybe try undoing what you did. Did you screw with any thing on the tb? Touch the tb set screw? Seriously, its not broke, just limp.
 

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your in limp mode, plate will never move unless you stomp the peddle to the ground in limp mode. Seems like you are new to the limp mode. Maybe try undoing what you did. Did you screw with any thing on the tb? Touch the tb set screw? Seriously, its not broke, just limp.
That's what I have been trying to tell him but he insist that there are "broken" parts. I was trying to save him from swapping out parts he isn't 100% sure that they are bad.

Just FYI he just recently install a turbo kit. I still think he needs to completely assemble and tune his kit and management before he assume that there are bad parts.

I have tried to explain to him the TB mechanism, where as it is not a mechnically driven plate, it's electronically controlled and drive by a motor and ECU.
 
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