ROW Flash, and Now Car Is Undrivable!
 

Sent my ECU, Immobilizer, and keys to ECU Doctors for a ROW reflash. They gave it a clean bill of health, and I reinstalled everything this morning.

Upon starting the car, the engine surges repeatedly, once about every second, from idle to about 2000 rpm. Up, down, up, down - goes on for minutes, with no change. Pushing the accelerator during this time has zero effect - even floored, the engine continues to surge, just as described before. The car cannot be driven.

-No- CEL lights or codes whatsoever indicated.

My question: Is there some sort of "reacquainted" deal that the car needs to go thru upon the reinstallation of an ECU so to get back together and sorted one to the other?

Obviously, during the period of time that the ECU was out of the car, the battery was disconnected, and I am 1001% certain that I reinstalled everything exactly as it came out - photos taken during the disassembly were used for reassembly, even though I do not see any reasonable way that the connectors for either the immobilizer or the ECU could be installed incorrectly.

I am at a complete loss here - Anyone ever experienced anything similar?

Thanks - DM


http://986forum.com/forums/uploads02...1520106948.jpg

Is it possible that they programmed it for an automatic car instead of a manual?

I think a call to ECU Doc's is in order... Do you have any other engine/exhaust mods? Maybe the flash didn't take properly?

If you haven't already, The Egas system needs to be remapped. Turn the key on for one minute, then off for 10 seconds then start the car

+1 on this. You need to do this to set the accelerator pedal.

Success!
 

That did it! I had figured that it was some sort of double-secret probation deal like that, and I followed your instructions to the letter, which did the trick!

911monty and NewArt, I owe you both a beer!

With MANY thanks for the vast knowledge base available on this forum - DM

P.S. - Now that it has been sorted, might I be so bold to ask how you knew of this "trick"? I did not find it in my Bentley's manual, and I don't recall seeing anything like this in the Owner's Manual.

The answer is in your response. In 20 years there is very little that has not happened previously and is why the general response of "DO A SEARCH" is the predominant response. The answer is most likely to be found in this vast database.... :cheers:

Now that I know what I was looking for, I found this (appears to be a) TSB via a web search.

Copied and posted here for posterity.

-----------------

Printed in Germany – 14, 2003

Note on adaptation

The DME control module must perform a learning and adaptation
routine for the throttle adjustment unit if:
♦The power supply to the DME control module is interrupted
♦The DME control module plugs are disconnected
♦A new DME control module is installed
♦The throttle adjustment unit is replaced
♦The DME is programmed.

To do this:

1. Switch the ignition on for 1 minute without starting the engine.
Do not actuate the accelerator pedal (for instance, make sure
that there is not a carpet pressing on the pedal).
2. Switch off ignition for at least 10 seconds.

The following conditions must also be observed, otherwise learning
is not possible:
♦Vehicle is stationary
♦Battery positive voltage between 10 V and 16 V
♦Engine temperature between 5 °C and 100 °C
♦Intake air temperature between 10 °C and 100 °

---------

All's well that ends well, I suppose, but I do now find it somewhat curious that I had no such drama recently when I replaced my battery, during which time the battery was out of the car for many hours.

Duh, forgot about that procedure. It should be followed anytime the battery is disconnected. It is also in the owners manual. Frankly, a note, or brief instruction sheet should have been included with your new toys.... I would still make that call.

Thanks for posting this instruction sheet. Although many of us hands-on people know this, there are surely twice as many here that don’t ! Glad that it worked for you.

Glad you got this sorted...
I recently replaced the timing belt, water pump and accessory belts on my 2002 4Runner. During the work, I had disconnected the battery. The battery was disconnected for about 10 days while I performed the job (amongst many unrelated chores). Upon getting everything done, I started the car and it barely ran for a bit and then died. I tried to start it again but it wouldn't start. My first thought is I must have screwed up the timing during the new belt installation. I tore stuff back apart and found my timing to be spot on. I reached in and tried to start the car and it started easily and idled smoothly! Given I didn't have the radiator connected yet, I turned the car off and buttoned everything back up.

I did a web search and low and behold, like the Boxster, the 4Runner looses its smarts when battery is disconnected for extended periods. I did not have an adaptation routine like the Boxster but if I would have just fought it and kept it running when I initially started it, it would have smoothed out within a minute or two. So now I know....

It sounds like you have done a remap but have never done the larger throttle body? As if you had you would have had to do the throttle adaptation then. It seems an odd way round to do the mods.

So how does the car run with the ROW map?

Stop the presses - Not right yet !
 

Yesterday's "Success" message as I posted here was based upon starting the car in the garage and revving it a bit. Seemed perfectly normal.

Today was my first opportunity to take the car out on the road. Just to be sure, I repeated the "fix" again for a second time as I posted earlier - this time I waited for 1-1/2 minutes with the key on, and then for 30 more seconds with the key off. Car started right up, revved like normal, and I thought that I was all set.

Drive for a mile an a half at slow residential neighborhood speeds, and again all is well.

Until.

With no warning (cruising at maybe 30 mph in 3rd), the throttle becomes non-responsive. At anything beyond about a quarter throttle, the engine drops to idle. I was able to coax it back home, basically idling in second gear. No further time to experiment tonight. As before, no codes nor CEL's.

My question now: Does the car require a learning period of some sort, so that it again learns how to play nicely with the ECU?

Why would it have been perfectly fine for the first couple of minutes, and then it all turns purple?

So, as before, the car is currently undrivable.

DM

Deleting the secondary oxygen sensor CEL warning.

Possible idea?
 

Maybe it is just too cold here:

♦Engine temperature between 5 °C and 100 °C
♦Intake air temperature between 10 °C and 100 °

Engine was cold, temps were about 37 degrees F / 3 degrees C.

Next move (tomorrow): Let the engine idle in the garage for a few minutes or so, in order to raise the temp of the air within the engine compartment. Then do the above procedure for a third time.

.... Seems like it certainly should not be this hard ...

Weird. I would guess something isn't right. No real reason for any of that to be happening. The relearn isn't that big of a deal, basically just a simple reset. You shouldn't need to do it over and over.

Have you done anything else to the car while the ECU was away?

On a UK car for the facelift 986 at least we still have pre and post cat O2 sensor. There is though only one pair of cats. You can though map out the post cat O2 sensor aftermarket.

Pausing To Take A Deep Breath …
 

Since my next window of opportunity to twiddle with this car will be next weekend, I now have plenty of time to take a step back and to think thru just what might be going on.

I am now of the belief that what I am seeing is not directly related to the ROW reflash, and that this work was done properly. Rather, my current hypothesis is that this is a consequence of the several months’ worth of time that the car spent with the battery disconnected, and the resulting need for the accelerator pedal to become properly reacquainted with the car’s electronics.

As a possible secondary clue, when I first hooked the battery up again this past Saturday, I surprisingly noted that none of my interior, nor my front / rear trunk lights, were illuminated.

The two (2) times that I have done the re-learning procedure this past weekend which I have posted above have both occurred with a cold engine and with the ambient (unheated) garage temperatures in the 30’s F. That is, below the noted 5 degree C temperature threshold as noted in the TSB above. For the second (latest) case, it now makes a little bit of sense to me that I calibrated the pedal to the car at too-cold temperatures. Then, as I started to drive around, the engine temperature slowly began to warm up, and after a mile or two the pedal developed confusion as to what it was supposed to properly do since it was now encountering some new “unfamiliar” warm temperatures.

If the above hypothesis seems correct (and I will be the very first one to admit here that it does seem completely unexpected), then the way to check this idea is to start the car next weekend and let it idle in the garage until a proper engine operating temperature has been reached. At that point, shut off the car and let the engine temperature warm up everything under the engine cover so to fall within the temperature guidelines noted above. At that point, re-do the learning operation for a third time, and see if that solves it. But if not, then the ROW work would become the next suspect to examine.

Based upon the above thought process, it now strikes me that anyone who lives in a cold climate, say, our Canadian prairie friends, who might disconnect their batteries for a several month long winter storage period must therefore have to go thru some sort of a secret ritual every spring so to get all of the electronics together and on the same page.

So, with this thinking out loud as the background, does any of the above ring true to anyone who disconnects their batteries for several months, and then tries to get their car rolling again once their seasonal temperatures are just above freezing?

Thanks - DM

Yup, completely understood. No cats.

i've had the battery out of my cars multiple times and never had to do a throttle remap. i think your car is having problems transitioning from idle. this can either be (a) an issue with the remap work that was performed, or (b) ecu not getting the signal to move from idle fuel maps to load fuel maps - throttle position sensor.

I know you guys have SAI. We don't use that. I'm still not clear on what spec engine you have and why the need for a remap. IIRC in early UK cars there is only a pre cat sensor but also post cat on facelift cars.

I put my car in storage from November to May in temperatures that go really low and disconnect the battery and never had to do anything when I start it in the spring.

hmmm - this might be the problem. MOST people who do ROW flash delete their secondary air injection system at the same time. with the SAI system still installed but no longer being controlled by the ecu, it might be getting a run signal but not a turn-off signal and confusing the o2 sensors as a result, which might be impacting the transition from idle to low load operation?!?!?

there is a connector on your sai pump (big black pump-looking thing located by a passenger air intake) - try unplugging it and see if the problem goes away?

And THAT is precisely why I use a battery maintainer here in CO. (not a trickle charger, they are different) I do get to drive on occasion in the winter, but the battery is never left to go completely flat. Never had an issue doing this with batteries for the last 25yrs.

To answer your ultimate question, I'm not sure that the relearn is that complicated. When I have disconnected the battery, I've never had an issue. And at time that has been when the car is dead cold and ambient temps are in the 30's.

Typically, the cause is whatever was last "fixed". I'd give ECU Doctors a call to see if they have any advice. Don't call and say that they didn't do the remap properly - just describe your problem and see if they have any ideas why this might be happening after the remap and suggestions on what to try next. Might be worth a phone call.

Guys – Many thanks to each and every one of you who have added your thoughts to this puzzle. I very much appreciate them all, and they’ve given me a number of issues to ponder. Thankfully I do have the unique circumstance here of not needing to rush into this, giving me ample time to do some research and homework.

Pouring thru my Bentley manual, page by page last evening, I finally stumbled across a pretty obscure paragraph, reproduced below:

“On ME 7.2 ( … which is mine) and ME 7.8 cars, the engine control module (ECM) software performs a learning and adaptation routine for the throttle unit if:

- The power supply to the ECM is interrupted (Me: Yup!)

- The ECM plugs were disconnected (Me: Yup!)

- A new ECM is installed (Me: Well, maybe sorta?)

- The throttle unit is replaced (Me: Nope!)

- The ECM is programmed (Me: Yup!)”


So, no question whatsoever that the throttle needs to be recalibrated. [One can perhaps wonder how, if a person were to unplug their battery for months at a time for winter storage purposes, that scenario might fit to the above five (5) bullet points – maybe ticking the box for Point 1?]

But in any case, the Bentley manual then goes on to paraphrase the contents of the TSB info that I posted earlier on in this thread, with the stern admonition (among others) that the min / max temperature guidelines which are noted in the TSB “MUST” be observed. And since my first couple of attempts to recalibrate the throttle did not abide by these temperature guidelines (at that time, who knew?), I am certainly not prepared to admit defeat, nor to cast any sort of blame.

So, while I do remain quite a bit surprised that their temperature window seems to be so strict as to make or break the success of this entire operation, nevertheless it all does appear to come together so to make some sort of logical sense. And so I will set to the warm-the-engine-up-first prelude that I noted earlier, for my third recalibration attempt to be done this coming weekend.

Since I’ve publicly come along this far, out here in the open on this forum, I will most certainly post updates - if for no other reason than to perhaps help out the next soul who might someday follow in these footsteps.

Sincere thanks once again to all - DM

- nope -
 

A week has now passed.

Garage temperature in the high 30’s F. Start car, let it idle. Seems fine. Goose the throttle every now and then, and it obediently revs like it should. Monitoring the coolant temps with my Autel real-time display.

After maybe 3 or 4 minutes, once the coolant temp reaches about 100 degrees F, the throttle ‘goosing’ starts to create the stumble, same as the previous time a week ago. Best way that I can describe it would be as if this were a carb car, and the accelerator pump jets are way too rich – the engine stumbles and will not rev.

Continue to let engine idle for maybe another 20 minutes. Idles just fine, but whenever the throttle is poked, the engine stumbles and is non-responsive, same old deal. Continue to let the engine idle until the coolant temp reaches a steady 180 degrees F, and then shut off the car.

Let the car sit for maybe 5 minutes, so to let the engine temps warm up the inlet air passages thoroughly. Turn on the key to calibrate the throttle – about 30 seconds into this, I hear some new sounds coming from the engine – sounds like a step motor tuning on and off a couple of times Then silence. After 90 seconds, shut off key, let sit for 2 more minutes. Then start the car.

No change, exact same symptoms as about a week ago – the engine simply will not run above maybe 2000 rpm. Just on the off chance, I try to drive the car around the block, but no go. I can do nothing but idle the car back home in second gear, and the car is again parked.

At this point in time, I cannot see anything that I have done incorrectly in order to re-calibrate the throttle. I hare followed the various instructions to the letter.

The only conclusion that I can now reach is that the ECU is buggered, and a friendly discussion with ECU Doctors will accordingly be done on Monday.

Thanks - DM

loose harness connector perhaps?
 

Dave, many years ago I had the exact same symptoms with my car (Fiat X1/9) but it had a Bosh FI and the problem ended being the connector that goes to the throttle body and then a second time on an Alfa Romeo and ended being the connector to the ECU

Pull the codes, I suspect you will get some related to one of the pedal potentiometer's signals being implausible. These codes do not light the check engine light. The pedal has 2 pots, one reports twice the voltage of the other. If the pots or wiring causes this to get out of range, the car goes into limp home mode. Make sure the second plug from the top is clean and seated properly on the DME.

These are from a 7.8 DME:

https://uniim1.shutterfly.com/ng/ser...729673/enhance

https://uniim1.shutterfly.com/ng/ser...729700/enhance

https://uniim1.shutterfly.com/ng/ser...729682/enhance

https://uniim1.shutterfly.com/ng/ser...729694/enhance

Paul -Thank you for the feedback, but that looks like some Durametrics screens, which I don't own. My Autel is not that smart.

Gave it one last try. Warmed the car up as before, noted the same problem. Shut off car, disconnected the battery, and removed the ECU. All of the 5 connectors had been seated well. Looked for bent pins or some other mechanical problem - nothing. Gently cleaned the pins with an old toothbrush and electrical contact spray cleaner, and flushed the pin's receptacles with the spray. Did not see any signs of mischief.

Reinstall ECU, triple check that all connectors are well seated. Plug in battery, and do the throttle reinitiation again with the engine in the proper temp range. Start car. No changes. Same old same old.

Sigh.

At this point, I am done fussing with it on my own, as I am comfortable that whatever it is, it's not an installation fault which I have created.

ECU Doctors discussion tomorrow.

Thanks again for your ears - DM

It's not a Durametrics screen it's a PST 2 screen.

Update:
 

The ECU, immobilizer, and keys will be sent back to Florida tomorrow, so to allow the ECU Doctors to have a thorough review.

I remain quite confident that they'll be able to sort it, so fingers crossed.

Thanks - DM

Update No. 2:
 

I have just heard back from the ECU Doctors.

They discovered a "software problem" present in the ECU, such that the ROW reflash "did not properly take".

I am assured that it has been all sorted now, and it has been shipped back to me, likely to arrive here the middle of next week or so.

Here's hoping that I can post a final wrap-up, once received and installed.

Thanks - DM

Fingers crossed!

Final Update, and Closure
 

I installed the second-time-around ECU and immobilizer this a.m., and then took it around the block. All seemed fine. I then used the car as one would do a "normal" car, running various stop-and-go errands on Saturday a.m. to a number of different places. All seems fine, and I even did a few second gear idle-to-redline full throttle pulls when I had a deserted road. All is now well.

As for the ROW tune, I note that I can now start the car without the clutch pedal engaged, and the SAI does not come on upon a cold start. While neither of these features were the point of the game, both serve as indicators of the new ROW tune.

--------

With hindsight, I am obviously disappointed that the ECU Doctors sent me my unit back with "problems" the first time around. However, they acknowledged the error, and were willing to step up to the plate and to see the situation thru for me. So, all in all, I would recommend ECU Doctors to others for this sort of work.

But just be certain to do this work during a time when you do not have any car deadlines to meet, as it can perhaps take longer than you might think so to sort it all out.

Signing off - DM

Been reading through the thread and cannot locate the purpose of the ROW flash.

Power?

Immobilizer delete?

See my posts nos. 15 and 20 on the first page!

Thanks, makes more sense now.