is 4 cylinder 2.4/2.7 ECM reprogramming/tuning possible?

I wanted to ask if this is doable? "somewhere" on the internet I saw a comment saying our computers aren't capable of being tuned but it wasn't a "trained" guy who said that AFAIK.

can you have your ECM reprogrammed or "tuned" on our first gens?

im not looking for performance, I just want a higher idle speed of 750 rpm instead of stock 650 rpm to smooth the rough idle these 4 bangers always have and im sure it wouldn't hurt to do any "fine tuning" of the system for best running (not to hop it up or anything)

is this doable? and if so where would you go to have something like that done?

 

hmmm, not a single reply?

ok then what about fooling the ECM then?

I know when the ECM detects the a/c is on it raises the idle speeds so is there a way to "fool" it by sending a signal to the ECM so it "thinks" the a/c is always on even when it isn't?

is it something like just needing a voltage signal on a certain wire leading to the ECM so it thinks the a/c is on?

 

I would like to know this also. 650 idle causes my exhaust to vibrate. Maybe we can tighten the throttle cable to run the idle a tiny bit higher?

 

nope, wont work, and you cant turn the throttle stop screw in to do it either. if you do it, at first it will work raise the idle speed for about 200 miles and then the ECM readjusts the fuel mixtures so it idles at 650 again and the screw keeping the TB cracked open creates an even and rougher idle then it normally does.

at this point in time, because its getting hot, I think running the a/c will solve the problem for now during the summer until it gets cool again.

just not sure if there is a way to tell it the a/c is on and be able to have the a/c off at the same time. the ECM is the only think that decides what the idle speed is. simply tapping into the wire will cause the a/c to run all the time as long as the voltage is there.

I am not good at reading detailed electrical schematics and figuring stuff like this out. if there even is a schematic of how the ECM works.

 

Damn that sucks. I just tightened my cable for the first time and I feel like I gained 5 pounds of boost LOL. Cali is starting to warm up so I guess I wont have to deal with the exhaust vibration until winter since Ill be using my ac also.

 

I'm just happy to hear that these 4 bangers all vibrate at idle and that it is normal. Never owned one before and have been thinking something is wrong. Now I won't worry about it anymore.

 

You might need a piggyback ecu Keakar,,to accomplish what you want.

I know your not looking for performance,,but what you want leans to that to smooth the idle or even raise it without the Ecu adjusting.

Fuel-Oxy-heat for idle control,,and you really need to be able to see what the ratios are,,to be fuel efficient and accomplish your goal.

 

what is a "piggyback ECU" ?

are you talking about something like this? http://www.amazon.com/Volo-Saver-Tuner-Toyota-Tacoma/dp/B004K6UK2I

or did you mean something like this? http://www.partsgeek.com/2j91mm9-toyota-tacoma-computer-chip-programmer.html

and yes im not caring about performance but I do understand they go hand in hand when you tune an engine, I just wanted to be clear im not wanting it to get more speed or anything, just a better running smoother idling engine.

I know Toyota "for a time" was swapping out ECMs from 95-97 to solve this rough idle by putting in ECMs that were hacked by toyota to have higher idle speeds but then they stopped doing this in 97. I just don't know why they didn't continue to make them with higher idle speeds to smooth out the rough idle feel?

the ECMs that were hacked had the same part numbers but the last digit was changed from 0 to 1 to identify the "hacked" ECMs

look here: http://www.askatech.com/AskATechLive/AatFileShare/References/FastTrack/TA141.pdf

I wonder why the ECM part numbers are different for each year? I was hoping maybe I could grab a used ECM with that #1 last digit from a 97 to put in my 99 but im always leary there will be unknown differences that cause issues.

 

man this sucks, on TV these mechanic guys just plug a laptop into the truck and put it on the dino and change anything they want to tune the trucks to run perfectly smooth so what would I need to do to do this with mine?

 

An example of a piggybacked Ecu. You still retain your oem one for all of the stuff it does, and add this on to adjust timing, fuel rates, ect. Whatever one might choose when working with those items.
http://www.lceperformance.com/LCE-Pro-Fuel-Injection-Kit-2-4-Cylinder-p/1063024.htm

 

On a '96 Japanese car I had (was OBDII of course) there was set of pins you could jump that took the ECU out of the circuit.

At that point you could adjust the throttle body to set a 'base' idle, and you could adjust the cam position sensor, using a traditional timing light, to set the base timing.

When you pulled the jumpers and put the ECU back in control, it just worked off those new base settings.

I have no clue if such a thing is possible on these motors. Probably not the timing, but maybe the idle?

 

Yah,,rip out our systems and go OBwanII. Then cut clearances and fab up sensor sliders on everything that needs one,,lol. Atrocious money to get that done,,but we could then adjust crap like that. It would make you bonkers during the process.

I really wish Toyota would have done that,,but they chose to dumb it down for a better bottom line,,for us pheasant parts replacers.

Aftermarket to the rescue!

Now we just get to jumper wire that same type of setup,,just to verify operation,,but no adjustment allowed per say until you spend cash'o.

 

so the poor mans solution is to turn on a/c year round to get higher rpm idle speeds then put in a toggle switch to cut off power to the compressor when not needed?

what about these two things? are they just junk or wasted money then?

http://www.amazon.com/Volo-Saver-Tuner-Toyota-Tacoma/dp/B004K6UK2I

http://www.partsgeek.com/2j91mm9-toyota-tacoma-computer-chip-programmer.html

 

Well, the Jet company has been in the bizz for a bit longer it seems. If I was to try one at a guess,,it would be the Jet programmer.

I would need more info and probably spend a few days just in the research. Phone calls to see how they handle things,,all the fun stuff before purchase.

 

I though jet was something different but based on these reviews its the same thing as the volo fuel saver with just options to read and reset CEL codes

http://www.amazon.com/67029-V-Force-Plus-Performance-Module/dp/B001M3ZKE0

I certainly don't want a whole new piggyback EFI system and certainly nothing at that kind of $$$ that's for sure

but if I could buy a replacement ECM chip that would allow programmability, then that would be more like a solution worth spending money on.

I saw somewhere you can mail your ECM somewhere and they could program it for performance and send it back to you in a few days but I don't see how they can do a proper ECM tune without the engine? I mean everything I know says no two engines run the same and so they all need a little different tune to "get it right"
I certainly wouldn't want to pay for a performance tune that did nothing to solve my hesitation and idle issues that's for sure.

 

I'm kinda been in the same boat, my 95.5 2.7l idles at 500 ish rpm with the air off according to the tach, funny thing is though, with my scan gauge hooked up it says it's idling at 750 rpm, which I know isn't correct because I can hear it, it's to low.

So I think my tach is correct, going to verify it for sure with a manual tach,,,,

So what this is telling me is either the ECM is not reading the rpm correct or the crank sensor is putting out the wrong info to the ECM, haven't really pursued it that much yet, but I know when I turn the air on and it bumps the idle up another 150 rpms, the truck preforms much better

 

ya, I think whatever sensor the ECM uses to determine rpms is not working correctly, not sure if that's the crank sensor or the cam sensor, its supposed to idle at 650 rpm if everything is sensing correctly.

did you or anyone mess with the throttle stop screw? if so set it back so it doesn't touch at all. when mine was set wrong it kind of floated between 600-650 rpms and acted like it wanted to die when stopped at red lights.

 

Just know one thing Keaker. Learning to "tune" has a HUGE learning curve and many will refuse to help you. You will need to know what all the sensors are and precisely what they do and how they effect other things. First thing to learn is how to disable closed loop so that you get data without the ECM changing things to the 14.7:1 stoich.

 

that's why you pay someone who knows what they are doing to do it, I have no intention to ever try it myself.

I know enough to know a little knowledge is more dangerous then anything so don't mess with stuff you don't understand.

I just wanted to know IF it could be done, then if it could I would find someone to do it for me.

 

I deleted my power steering, and if you take one of the vacuum lines and put it on to the other port for the power steering pump it idles a bit higher