High idle or maybe its normal

[ViperGTS14]

Hi guys, What does everyone stock gen 5 rpm idle at? Mine is around 900-1000 rpm which seems like of high. If this is to high any suggestions as to what it could be?

[Gen5snake]

I'm not familiar with the Vipers throttle body, but assuming it's like most modern throttle bodies, a high idle would usually indicate a stuck idle air control valve. It also could be that you need a throttle position re-learn...meaning your throttle needs to be re-calibrated. That can be done by the dealer. I think my Viper idles around 750 rpm.

[ViperGTS14]

Would hope that is not the case. Will report back once I have more information.

[ViperSRT]

How many miles? If I recall the idle was higher for the first thousand or so miles.

[ViperGTS14]

8,500

[Policy Limits]

Goes from 1100 for first thousand miles down to 750 after break in. I broke in two gen 5's this way. I'd try several cycle/ restarts if you're past breakin to avoid your typical dodge dealer.

[ViperGTS14]

Goes from 1100 for first thousand miles down to 750 after break in. I broke in two gen 5's this way. I'd try several cycle/ restarts if you're past breakin to avoid your typical dodge dealer.

So want to avoid the dealer if I can. Wondering if I should unplug battery as well.

[chris_lee]

Mine sits at 725-750 idle.

[ViperGTS14]

Damn, this sucks somethings not right then. Just took a video of start up and running and its stays at 1000 rpm with the ac on or off and after 15 min's of run time full temp.

Called the dealership whom did the check engine light repair (crank sensor), they want me to come in tomorrow and have there Viper tech scan to see if what they did was the issue. Since its out of warranty seems I will have to pay if its not under the powe tran warranty. :-(

[Jack B]

There is no IAT, idle is controlled by the PCM. Put a scan tool on and look for codes. You may need a throttle relearn. When you use the scan tool, note what the idle vacuum is.

[ViperGTS14]

There is no IAT, idle is controlled by the PCM. Put a scan tool on and look for codes. You may need a throttle relearn.

Scan just now, no codes. Agree, most likely need throttle relearn. But my question is why? Why now or what did the dealer do when they did the crank sensor fix.

[Steve M]

Just make sure they retightened everything...as Jack said, there is no traditional idle air control valve on these cars or any drive by wire car. That functionality is performed by the PCM simply cracking the main throttle blades.

[ViperGTS14]

I'm totally following the concept of what is needed, just not sure why its needed after why did a crank sensor replacement. Meaning what the hell did the change to the PCM/ECU that cause this high idle.

BTW this is what they perform I'm thinking

https://www.youtube.com/watch?v=5uEfhQOWhYI

[camarochevy1970]

have you tried disconnecting the battery for a few minutes and hooking it back up just to see if it straightens it out?

[ViperGTS14]

Yes I did. Nothing :-( Also cancelled my appointment. Would rather take it to a different dealer whom is said to be a little more Viper knowledgable

[Jack B]

Scan just now, no codes. Agree, most likely need throttle relearn. But my question is why? Why now or what did the dealer do when they did the crank sensor fix.

You answered your own question, they did not do the throttle relearn? Just a guess, you would have to be lucky for the car to run if they did not do the relearn.

[ViperGTS14]

Honestly, don't know which process is involved when they do a crank sensor. Might be some PCM reprogramming, yet again I don't know.

She runs like a rapped ape, smooth as silk upstairs no issues in that regards, just idles about 200 rpm more than it should.

[Gen5snake]

Honestly, don't know which process is involved when they do a crank sensor. Might be some PCM reprogramming, yet again I don't know.

She runs like a rapped ape, smooth as silk upstairs no issues in that regards, just idles about 200 rpm more than it should.

How many miles ago/runs cycles was the crank sensor replaced? If it runs good, let it be.

[ViperGTS14]

My guess would be 4-5 cycles, possibly 50 miles if that. I doubt it has to go through the whole beginning stages as if its a new motor thingy again. Searching around it seems everyone did have high idle for the first "x" amount of miles.

I would let it be since it runs great but knowing its not meant to be at that RPM at idle has me concerned something isn't as its meant to be.

[Gen5snake]

My guess would be 4-5 cycles, possibly 50 miles if that. I doubt it has to go through the whole beginning stages as if its a new motor thingy again. Searching around it seems everyone did have high idle for the first "x" amount of miles.

I would let it be since it runs great but knowing its not meant to be at that RPM at idle has me concerned something isn't as its meant to be.

I have a feeling this is tied to the new crank sensor and will rectify on its own after some miles/start cycles. The MAP (Manifold Absolute Pressure) sensor has a part in idle control/fueling, hence some previously mentioning looking for a vacuum leak. The sensor replacement procedure didn't mention anything about throttle re-calibration. Give it a couple more miles/starts and see what happens.

[ViperGTS14]

I have a feeling this is tied to the new crank sensor and will rectify on its own after some miles/start cycles. The MAP (Manifold Absolute Pressure) sensor has a part in idle control/fueling, hence some previously mentioning looking for a vacuum leak. The sensor replacement procedure didn't mention anything about throttle re-calibration. Give it a couple more miles/starts and see what happens.

I'm hearing you, will report back.

[Jack B]

I have a feeling this is tied to the new crank sensor and will rectify on its own after some miles/start cycles. The MAP (Manifold Absolute Pressure) sensor has a part in idle control/fueling, hence some previously mentioning looking for a vacuum leak. The sensor replacement procedure didn't mention anything about throttle re-calibration. Give it a couple more miles/starts and see what happens.

There has to be a separate relearn on the new crank sensor. However, it could be done by the pcm. Point, that procedure might have affected the throttle relearn??

[ViperGTS14]

There has to be a separate relearn on the new crank sensor. However, it could be done by the pcm. Point, that procedure might have affected the throttle relearn??

Got me guys, wishing I was there to talk to the tech who did the crank sensor job I'd surely have asked and noticed that the RPM was higher. I do appreciate the kind help everyone has given me. I've had a plethora of cars, been on many forums as well. The guys here are truely after helping which is what I'm about as well, glad to be apart of the community.

[Gen5snake]

There has to be a separate relearn on the new crank sensor. However, it could be done by the pcm.

That's what I'm thinking that this may be from the new crank sensor...and the idle relearn is driven by the PCM...but not linked to the throttle position relearn routine. Like after x amount of crank rotations, the idle would normalize. I'm just speculating...pulling this from my rear. I wish we had a source on here that took part in the programming of the PCM....this way we would know for sure.

[ViperGeorge]

Doesn't a new crank sensor require a TER relearn? Essentially they have to put the engine through diagnostics that relearns the error correction of the flywheel. This allows the the PCM to know how to calculate when a cylinder has actually fired when reading the crank sensor. Without doing this the PCM can think a cylinder fired at slightly off timing. This can cause the PCM to try and constantly adjust the firing of the cylinder incorrectly. It can also throw a P030x engine mis-fire code.

My 14 GTS came from the factory with an improperly set TER and had to be redone. Problem then was that a software update to the WiTech system uninstalled the pages needed to do the relearn. Dick Winkles had to get on the phone with the tech to go through an alternate manual procedure. I think the pages were reinstalled with another software update.