T-SB-0044-14 Feedback: Engine ECM Reprogram [Pinging]

id be willing to bet they arnt going to care as they are only opening the hood to look at and replace a sticker.

 

Let us know what happens

 

It pulls OD much better at speeds around 45-50. When running 87(CA summer gas), there was a very noticeable flat spot if you tried to accelerate at 1/4 throttle in OD after coasting down to around 50. This is where it would start pinging as well. Running 91 would cure it. But now it's even better.

 

i like the sound of that!!!!! as i too have noticed the flat spot around that speed range in lockup... its like... you put your foot in it and it goes no where till it unlocks.

 

I would say you're a candidate to have the TSB performed. Best bet is to print out the .pdf attached TSB on my original 1st post, and bring it to your dealer with regular unleaded fuel.

 

I just gave my printed copy of the TSB to a friend who has a 2013 DCSB Off Road V6 with the pinging issue. I'll chime in and let you know about the result of the TSB on his truck.

 

Ok, I'm on tank 2 87 octane and still no knock since the TSB.

 

I had this done last week and my ping is gone. My truck has never sounded this good it is really night and day difference. This is what it sounded like before I had the tsb done. https://www.youtube.com/watch?v=ZHGQfHTWh-0&feature=youtu.be

 

wow, that sounds HORRIBLE!

 

And that's with 97.

 

and the tsb fixed it!?!?!?!

 

It sure did! The whole engine sounds great and it could just be me but it feels smoother when driving and at idle.

 

I wanted to post up what I know about these type of reflashes for the PCM/ECU. Some of this you all may already know, but I want to leave out no details, so that if someone DOESN'T already know this, it will be apparent.

Ignition "ping" or "knock" is what happens when the fuel in the cylinder is ignited prematurely, be it by timing itself, or by excessive heat. Too much pinging can cause piston damage, and reduced engine power, as the fuel is ignited BEFORE the best time for maximum power. There is a fine line between ignition timing and power. Back in the day we could advance the timing on our own by adjusting the distributor. This would give us a gain in power if done correctly, but often would have the bad effect of excessive engine heat.

Today's modern engines use electronic advance timing, also called variable ignition timing, (do not confuse with variable valve timing) to improve fuel economy, as well as power output. Most engines are under the most extreme load between 1500 and 2000 RPMs. Engine maximum horsepower is usually higher than 3000 RPM. So the timing, and response to changes in timing, at these two RPM areas are totally different. Your knock sensors are simple an input to the ECU, and do not actually control anything. They simply use a crystal that is tuned to respond to specific frequencies and send a signal to the ECU that knock is present, or not present. When you are driving your truck under load (and this is ANY load, be it normal acceleration, or towing) the ECU will advance the timing to a preset "power" band that is calculated based on a number of data parameters to include engine load, RPM, throttle position, gear, MAF data, air temp, etc. If, when the ECU has advanced your timing to the preset advance the knock sensor sends a positive signal to the ECU indicating spark knock, then the ECU will reducing the timing advance by the maximum amount until the knock sensor signals a negative response. After this it will slowly ramp up timing advance until the sensor signals positive again. That is current NORMAL operation. Because of this the Tacoma has a major power loss as soon as this ping occurs because the timing is at a major reduction.

In comes the TSB that is designed to fix this issue. Techs are not privy to what is being done, as all manufacturers keep almost every bit of the code under wraps as much as possible. As techs we do not have access to this code, nor do we have the ability to change any of it ourselves. What the code in general is doing, is managing the electronic timing advance better than it has been. This is done by slowly reducing the timing advance until the knock goes away, instead of eliminating ALL advance, then going up. Of course "slowly" in an electronic sense is still within fractions of a second. The end result will be that the ping/knock will be reduced or even totally eliminated, while allowing for as much horsepower as possible. This means that no top end horsepower will be affected (Since pinging does not occur at the horsepower top end RPM range) so the engine max HP is not affected. Also, under normal driving, your engine is not under the most severe load at cruising speeds of 55 MPH, so your fuel economy will not be affected either. Actually just the opposite. If you do a lot of city driving, where you are doing a lot of stop and go, you should actually notice the same, if not slightly better economy, as an engine that does not ping performs better than one that does ping.

At GM we had this exact same problem in the early 2000 model Cadillac Northstar engines. Excessive ping, even under high grade fuels. They came up with a reprogramming for them, and the ping was gone, and many customers actually said the engine performed better than ever since the timing was not retarded.

 

I hope some one can chime in! I have ping at low rpm with no boost! Wonder if this tsb is for canada too

 

I'm in for this one too... after drive home, coming up hill to my house with engine hot, right about 1500 rpm, pings like crazy for the whole block. WIll check it a couple times but at least i have time to get this done at next oil chg.

 

My '12 has been doing the pre-ignition ping in hot weather. It was really noticeable last week when we had a heat wave and running AC, 104 F for a couple of days. It was fine if I didn't let the engine lug down in that RPM range or try to accelerate from that RPM range. Really just manually downshifted the auto trans, accelerate and it was fine. I'm probably going to have the reflash done after reading this thread.

 

I'm picking mine up from the dealer in an hour. I handed th rep the PDF print out and was told the shop foreman would handle it. We'll see. I'll post updates

 

Seems to be fixed...regular octane

 

Great info above

 

Thank you for your input! Good lesson on engine ignition =).

Good. Thanks much for the feedback