Malone stage 2 regen behavior?

Does the stage 2 software totally eliminate regen behavior? I was idling waiting for my wife for about 10 minutes last night when RPM increased from 800 to 1k. It wouldn't go back down until I restarted the engine. Seems an awful lot like regeneration.

I've noticed this happen once before but didn't think much of it.

My stage 2 software has the EGR and ASV deleted plus econotune fuel mapping.

I have not noticed higher idle on mine.

IIRC it only does this if you have removed the dpf. As long as the dpf is in place it needs to regen. If it is gone you must have the extra fueling removed from the tune. You can have stage2 with or without the dpf in place from my understanding. When cold it will also fast idle.

Lightflyer1 said:

IIRC it only does this if you have removed the dpf. As long as the dpf is in place it needs to regen. If it is gone you must have the extra fueling removed from the tune. You can have stage2 with or without the dpf in place from my understanding. When cold it will also fast idle.

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I forgot to mention in my OP that the DPF was deleted as well.

Last night was the first time I really observed this behavior in detail. It was also very cold; about 24F at the time I noticed and the car had only been idling for about 7-10 minutes total. So, coolant and block still had not reached optimal temperature.

Basically, I was sitting in the car looking at my phone when I noticed that RPM suddenly and quickly jumped from 800 to 1000 RPM. What had me baffled was that the car had been idling at 800 for about 7-8 minutes by that time. If the RPM increased due to a fast idle request from the ECU due to ambient temperature, wouldn't it happen right at engine start? This is why I thought it seemed more like a regen operation. I did not notice the cooling fans kick on which would normally happen during an actual regen cycle.

I guess I better call Diesel Dubs or Malone to ensure that the extra fueling was removed from the tune, although I'd assume that to be the case since the DPF is gone and I don't have any fault codes stored.

Edit: I also had cabin heat on full blast; could a fast idle condition have started because of that?

I only ever see mine at 1k at cold start up until it is slightly warm, then it goes back to 800. Like you said maybe it jumped because of ambient temp. What was your temperature gauge at, at the time?

Also, wouldn't you have also noticed a sh*tload of steam/smoke coming out of the tailpipe without the dpf on, if it were actually in regen mode?

jay_fyp said:

I only ever see mine at 1k at cold start up until it is slightly warm, then it goes back to 800. Like you said maybe it jumped because of ambient temp. What was your temperature gauge at, at the time?

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If I recall, the temp gauge was still in the cold area when the fast idle started; probably somewhere near the first bold hash mark.. so maybe at 1/8? Car was idling for about 7 minutes when RPM jumped to 1000.

Also, wouldn't you have also noticed a sh*tload of steam/smoke coming out of the tailpipe without the dpf on, if it were actually in regen mode?

jay_fyp said:

Also, wouldn't you have also noticed a sh*tload of steam/smoke coming out of the tailpipe without the dpf on, if it were actually in regen mode?

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True, didn't think about that. Yeah, nothing extraordinary noticed coming out of the tail pipe during that time. So, probably just a delayed fast idle... car was coming out of a warmish garage (maybe in the 60F range?) to idling outside on a Manhattan street at 24F.

amstel78 said:

True, didn't think about that. Yeah, nothing extraordinary noticed coming out of the tail pipe during that time. So, probably just a delayed fast idle... car was coming out of a warmish garage (maybe in the 60F range?) to idling outside on a Manhattan street at 24F.

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Yep you got your answer. I even un-intentionally did an experiment tonight. Initial start up was the usual 1k RPM, pulling out of my street (1/2 mile) onto the highway I was already at 800 at idle. I rolled along till the first red-light still at 800, turned on the heat to setting #2 and sat idle for a minute or two, idle went back to 1k briefly. It resolved quickly after to 800 after driving again and never went up.

Thanks Jay. Anyway, another 4 hour reset and back to work I go. After today, I've worked almost 40 hours since Monday.

Sent from my rotary telephone

Mine is stock and I notice when it is cold out that it shows temps rise similar to a regen after about 5 or so minutes of running. This only lasts about 3 minutes then it returns to normal. I use the Torque app and can see the temps for pre turbo and pre and post dpf. We are having a cold snap here in Texas right now so it is the only time I will probably see this. Maybe there is something that elevates it temporarily when cold. If you have the dpf removed and tuned I would imagine they deleted the stuff for regens.

I think it's supposed to do that to keep warm.

miahallen said:

I think it's supposed to do that to keep warm.

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Doesn't apply to the CR.

Do you have Climatronic? If so, it sounds a lot like a fast idle command for the electric cabin heater. The manual climate control may also be able to command fast idle - I don't know.

VeeDubTDI said:

Do you have Climatronic? If so, it sounds a lot like a fast idle command for the electric cabin heater. The manual climate control may also be able to command fast idle - I don't know.

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No climatronic but I do have the electric auxiliary cabin heater.

03_01_TDI said:

Doesn't apply to the CR.

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Oh, OK...nvm

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amstel78 said:

No climatronic but I do have the electric auxiliary cabin heater.

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Definitely what causes it. I again un-intentionally saw it happen tonight. Cold start at 1k. Went down to 800 shortly after (no heat on), cranked the heat to #3 after a few minutes of driving and at the red light jumped back to 1k. After the engine was completely warm, I didn't notice it again. Whatever the case may be, it's normal, and you're for sure not in regen mode which we already know, so no worries.

Good to know Jay. Thanks again.

Happy Thanksgiving to everyone!

Yep, if you have the heater set to max hot and turn the fan up, if the motor is still cold it'll turn on the aux electric heater. This will cause the car to idle at 1000rpm so that the alternator is creating more juice for the heater.

This fast idle is due to cabin blower and chill outside temperatures.if you want to avoid the fast idle, just switch off the cabin blower. Stock tune does that too.

When its really cold you will have high idle, not sure why it would start at 800rpm then idle up to 1000rpm? Mine goes straight to about 1000rpm then backs down to 800 after a little while.

If you don't get lots of white smoke randomly, its not a regen. And its definitely not gonna regen on a cold engine. Maybe your coolant temp sensor is acting funky and that is why its idling up shortly after starting.