Engine revving up highly with the same gas pedal press but speed dropping

[mxanotcar]

12/31/2104 Temp 26F. Time about 7am. Driving on local road after backing out parking lot after 12hour parking:

 

About 25MPH-40MPH, I did not speed up and the gas pedal remained the same, and suddenly a huge engine noise came on (later realized it was the the engine revving up highly) but the car did not speed up.

 

Released the gas pedal, applied the same amount of pressure of the gas pedal (87% still to go more if pedaling all the way to the metal), car was still rolling, and the same high engine revving up.

 

I dropped the speed down to about 10MPH, and slightly apply the gas, and a few seconds later the same high revving engine came on.

 

Released the gas pedal, and repeat until I could find the shopping area to stop.

 

At stop in the parking lot, turned the heat to max for 5mins, after that, turned off the engine for 1mins.  Turned car back on, and drove as normal without the high engine revving up.

 

01/02/2015 Temp 29F.  After 12hour parking, time about 7:20am on local road and about 7:40am on highway:

 

The same thing occurred one on the local road, and one on the highway.  In these two times, I released the gas pedal, and re-applied the same pressure on the gas pedal, and there were no high engine revving up and the speed increased as normal.

 

There are two engine noises as the car moving that I have noticed up to now:

1. Also a huge noise but more like an OMMMMMM.  A huge OMMMM noise as the ICE kick in to the speed.  This one seems to be normal although it always came on suddenly even without pressing the gas pedal further more, and the car speed does not drop and the car can go faster when pressing down the gas pedal.  This OMMM noise has been happening since the date I got the car.  It happens from time to time.  One big OMMMM and then it blends down to regular operating engine noise.

 

2. The new high engine revving (like a screeching) noise as describing from the begining this post.  This one is different from the number 1.  There is no initial big OMMM, but it is as if the gas pedal pressing down to the metal until the gas pedal release.  And the car speed drop, no acceleration.

 

I could take the car to the dealership.  They could probably find something wrong with it IF they can reproduce the problems.  I doubt they can reproduce the problems without having the car at the dealership for days and days.  I have no doubt if I described to them as to what described here, I would have the similar reactions and responds that I received when I described to them about the dead car from the 12V battery problems which should be widely known by now.

 

Hopefully, this new engine high revving noise is one time thing like several others one-time occurrences with the CMAX Hybrid.

 

Mileage: ~35,800 miles.

 

At purchase, I was debating about the Hybrid or Energize.  I was thinking that let's try out the base model, if all goes well/normal, I would upgrade to an Energize.  May be it I got the Energize then, then there would be no issues.  It is a good to great car in its class, but it is not normal to have these issues.

 

[plus 3 golfer]

Sure sounds like the transmission or power train control modules are getting confused  I would definitely take it to the dealer to check for codes.

 

Also, can you check in the Engineering Test Mode (ETM) screen to see if there are any Diagnostic Trouble Codes stored?  Unfortunately  we have yet to find the "key" to translate them. This may help others in the future if DTCs are stored.

 

Entering ETM with Keyed Ignition

From Kotsby: Engineering Test Mode (ETM) is activated on the SE by holding down the left-steering-wheel OK button when turning the car from off to ignition-on and holding OK until the ETM display begins (a yellow ET is displayed in the upper left corner) of the left-hand screen).

 

It is not necessary to actually turn the key another notch to "start" the vehicle. The only way to turn off ET is to turn the key off. Once activated, ET will continue on the left-hand display once the vehicle is started, covering the usual left-hand trip odometers, MyView, and Power screens.

 

Entering ETM with Push Button Start

1) Push and hold the "OK" button on the left input pad on the steering wheel

2) DO NOT STEP ON THE BRAKE.  Push the start button while still holding the "OK" button.  

3) Engineering test mode will come up on the left hand screen.  It might be blocked by another message  but you can see the letters ET in the upper left.  Release the "OK" button and push it again to clear the other message.

4)  The Engineering Test Mode screen should be displayed.

5) Push the up or down arrows to scroll through the ETM screens.

 

 Here's what Ford says about the ETM DTC screen:

• DTC HIST CURR
• xxxxxx x x
• xxxxxx x

Displays all of the Diagnostic Trouble Codes (DTCs) set (history and current Diagnostic Trouble Codes [DTCs]). An X in the HIST or CURR column means the DTC is active. Three Diagnostic Trouble Codes (DTCs) display on each screen. If more Diagnostic Trouble Codes (DTCs) are present, there will be additional screens listing them. If there are no Diagnostic Trouble Codes (DTCs) in history or current, the display will only be the title row. 

[hybridbear]

Also, can you check in the Engineering Test Mode (ETM) screen to see if there are any Diagnostic Trouble Codes stored?  Unfortunately  we have yet to find the "key" to translate them. This may help others in the future if DTCs are stored.

The "key" can be found by purchasing an OASIS subscription. It defines all the codes stored by all the modules. PM me if you have codes that you are wondering about and I'll look them up in OASIS. The mods at the Fusion Hybrid & Energi Forums share an OASIS subscription since it helps so much in tracking TSBs, SSMs & more. The mods here may want to consider doing the same thing. The subscription is about $100 per year.

 

 

12/31/2104 Temp 26F. Time about 7am. Driving on local road after backing out parking lot after 12hour parking:

 

About 25MPH-40MPH, I did not speed up and the gas pedal remained the same, and suddenly a huge engine noise came on (later realized it was the the engine revving up highly) but the car did not speed up.

 

Released the gas pedal, applied the same amount of pressure of the gas pedal (87% still to go more if pedaling all the way to the metal), car was still rolling, and the same high engine revving up.

 

I dropped the speed down to about 10MPH, and slightly apply the gas, and a few seconds later the same high revving engine came on.

 

Released the gas pedal, and repeat until I could find the shopping area to stop.

Was your shifter accidentally in Low instead of Drive? Having the shifter in Low causes the engine to rev up very loudly.

[mxanotcar]

"Was your shifter accidentally in Low instead of Drive? Having the shifter in Low causes the engine to rev up very loudly."

I looked at it, and it was on orange D not L or N.  If on L, it would still accelerating but it was not and the speed was slowly dropping.

 

Currently, waiting for another 10mins time to post another PM message "You cannot start another PM topic . . .. .. " for another 10mins.

 

All DTC numbers have the X marked in the HIST column.

 

It looks like Plus 3 Golfer member "can not use the messaging system", error from messaging.  I also sent the DTC to hybridbear.

[plus 3 golfer]

...

 

It looks like Plus 3 Golfer member "can not use the messaging system", error from messaging.  I also sent the DTC to hybridbear.

I have PMs off as in other forums I would get PMs with questions on what do I think is the issue, what should I do, what do you recommend and so forth.   I felt obligated to respond and spent to much of my time researching issues.  Post the codes so everyone knows what the codes are. :)  ;)  

[mxanotcar]

There were serveral times of the same high engine revving up after I wrote down the numbers below.  I re-looked at the ET screen again when I got the chance, and the same number displayed.  I do not think the high engine revving up is stored in DTC codes.

 

It is very very difficult to reproduce the issue (whatever it is causing the high engine revving up during normal driving conditions).  It does happen again (but not often) since the day it first happened.  This morning, temp 20F, between 30MPH and 40MPH, it came up again.  And it came up again at right about hitting 40MPH mark with the gas pedal unchanged (no releasing or further pressing).  As soon as I heard the revving up (I knew that noise now), car continued rolling but no acceleration, released the gas pedal, pressed the gas pedal to same level when the previous revving up occurred, and car accelerated passing the 40MPH mark as normal.

 

I have tried again for about the same speed as above but high revving up did not come up.  Also, the HV battery can drive car during those speed, sometimes HV sometimes ICE sometimes both, and now adding high engine revving up without acceleration.

 

Also, MyView is set with the usage of kW of ICE and HV battery so I know when the ICE kicks in or driving in HV or both.  And the high engine revving up has happened around when the first 2 white marks are fully white during ICE.  During those time of high engine revving up (HERU), that noise came on but the white marks barely pass the 2nd white mark.  On the normal acceleration (without HERU), the 2nd white mark is passed immediately and fast, and car accelerates as normal.

 

Here are the numbers all marked with HIST:

C14600
C29300
C40181
C41282
C41581
C41582
C42082

Edited January 7, 2015 by mxanotcar

[mxanotcar]

I might have found a way around the high engine revving up (HERU) and no speed acceleration on unchanged gas pedal pressure while driving with D(drive) shift:

 

Thursday 1/8/2015.  Temp 8F.  Time around 7am.  As reaching 10MPH (unlike 30MPH to 40MPH previously), the HERU kept happening so I released and then eased in the gas pedal for each time the HERU occurred.  Finally got to 60MPH, the HERU went away and acceleration was normal.

 

Friday 1/9/2015. Temp 26F.  Time around 7:15am. The HERU happened again around 30MPH to 40MPH, and this time as soon as I heard the HERU loud noise kicked in, I pressed the gas pedal a bit further down to accelerate and the HERU loud noise disappeared almost right away.  And the car accelerated normally.

 

After 1/9/2015 HERU espisode with the work around, I have not heard HERU come on anymore (hopefully that is the last of it).  If it happens again, just need pressing a bit on the gas pedal (and really mind the traffic) to get the car accelerate to stop the HERU.

 

This is another one of bizzare things that CMAX Hybrid does, at least mine anyways.

[ScubaDadMiami]

Sometimes, the transmission selects a lower gear equivalent or higher when you depress the pedal. If I work it gently, it will keep to a lower, quiet RPM. With just a slight increase in pressure, I really hear ICE revving much higher. Could this possibly be what is going on?

[plus 3 golfer]

So has hybridbear found out what the codes mean? Have you taken the car to the dealer yet?

[FordService]

There are two engine noises as the car moving that I have noticed up to now:

1. Also a huge noise but more like an OMMMMMM.  A huge OMMMM noise as the ICE kick in to the speed.  This one seems to be normal although it always came on suddenly even without pressing the gas pedal further more, and the car speed does not drop and the car can go faster when pressing down the gas pedal.  This OMMM noise has been happening since the date I got the car.  It happens from time to time.  One big OMMMM and then it blends down to regular operating engine noise.

 

2. The new high engine revving (like a screeching) noise as describing from the begining this post.  This one is different from the number 1.  There is no initial big OMMM, but it is as if the gas pedal pressing down to the metal until the gas pedal release.  And the car speed drop, no acceleration.

 

Mileage: ~35,800 miles.

 

Sure sounds like the transmission or power train control modules are getting confused  I would definitely take it to the dealer to check for codes.

 

 Mxanotcar,

 

I agree with Plus 3 Golfer, and recommend taking it in to a Ford Dealer to get diagnosed.

 

Let me look into this further. Which model year is your C-MAX Hybrid?

 

Was your shifter accidentally in Low instead of Drive? Having the shifter in Low causes the engine to rev up very loudly.

Sometimes, the transmission selects a lower gear equivalent or higher when you depress the pedal. If I work it gently, it will keep to a lower, quiet RPM. With just a slight increase in pressure, I really hear ICE revving much higher. Could this possibly be what is going on?

Hey guys,

 

Thanks for stepping in to help a fellow Ford Family member! I’m extending some love as well to help keep your vehicles in tip-top shape. Go to the Ford Owner website, and use the Maintenance Schedule. This tool makes helpful recommendations on when to service it next.

 

Tricia  

Edited January 13, 2015 by FordService

[mxanotcar]

Thanks.  I will take the car to the Ford dealership, that I have been going for the services, on its next oil change for the diagnostic (may be after the diagnostic, they can feed it some kind of asprins :) ).  I have changed MyView from kW output to tach rpm output as hybridbear suggested. I'll be on the look out for that strange and almost like screeching noise with higher than normal vibration (noticeably can be felt from the steering wheel) for the normal driving conditions and without speed gain.

 

The described increasingly loud noise, until gas pedal is released or pressed down a bit further to accelerate, is different from the high rpm.  I tried to speed up from 0 to 40MPH (no traffic) within 10secs to see if the high rpm sound is the same as that noise, and it was different.  It could be gear auto-shifting confusion during, or rather immediately before, the strange loud noise espisodes.

 

And the model is 2013.  I think it was made or rolling off assembly line on September 2012.

[joe]

If it wasn't for the lack of acceleration, I would suggest  that maybe the noise suppression system is failing, allowing for previously masked engine noise to enter the cabin.  I know it's a long shot but occassionally I will hear unusual engine noise and wonder if the noise suppression system is taking a time out.

[FordService]

Thanks.  I will take the car to the Ford dealership, that I have been going for the services, on its next oil change for the diagnostic (may be after the diagnostic, they can feed it some kind of asprins :) ).  I have changed MyView from kW output to tach rpm output as hybridbear suggested. I'll be on the look out for that strange and almost like screeching noise with higher than normal vibration (noticeably can be felt from the steering wheel) for the normal driving conditions and without speed gain.

 

The described increasingly loud noise, until gas pedal is released or pressed down a bit further to accelerate, is different from the high rpm.  I tried to speed up from 0 to 40MPH (no traffic) within 10secs to see if the high rpm sound is the same as that noise, and it was different.  It could be gear auto-shifting confusion during, or rather immediately before, the strange loud noise espisodes.

 

And the model is 2013.  I think it was made or rolling off assembly line on September 2012.

Thanks for the update, mxanotcar.

 

Please contact me when you take it in to get serviced, and I’ll be happy to get this concern escalated at that time!  :) 

 

Tricia

[mxanotcar]

Update to the (1.) strange loud screeching noise, (2). with high vibration from steering wheel to the floor on the driver side, (3.) even on the passenger side in the front area WHEN THE TEMPERATURE below 32F:

 

The temperature has finally lunged down below 20F, during the mornings, since this Monday 1/4/2016.  Every early morning since this Monday, the temp was 17F,14F, and 19F this morning, the same 1 2 3 described above continue to happen, and always start with 1. came on first then the 2. then 3. (there are times: 3. then 2.).

 

Driving speed is at the normal local road, and at hi-way.  Normally those 1 2 3 stop when I reach hi-way speed after 15mins in driving, but this morning when I tried to accelerate on the hi-way, 1. sound came up and since I continued pressed down the gas pedal, it went away. :)

 

2 ways when the 1 2 3 happen: release the gas pedal or press down the gas pedal and the strange symptoms disappear (until the next occurrences).

[rjam]

I have a new CMAX SEL While driving at 63 mph the ice revved way high on three occasions. All freeway, all going downhill. The hill was quite steep and would not require the ice to run at all. If it were a standard 4 cry engine I would think it was past redline. Sure gets your attention. Stepped on the brake and it went away the did it twice more on this trip. Haven't driven on the freeway again. 1200 miles on the car when it went nuts. Didn't seem to hurt anything however.

[plus 3 golfer]

I have a new CMAX SEL While driving at 63 mph the ice revved way high on three occasions. All freeway, all going downhill. The hill was quite steep and would not require the ice to run at all. If it were a standard 4 cry engine I would think it was past redline. Sure gets your attention. Stepped on the brake and it went away the did it twice more on this trip. Haven't driven on the freeway again. 1200 miles on the car when it went nuts. Didn't seem to hurt anything however.

Sure sounds like you had Grade Assist on (button on side of shifter).  If so, ICE was just spinning (no fuel injection) to maintain speed via engine braking going down hill.  There are many posts on Grade Assist.

[stevedebi]

I have a new CMAX SEL While driving at 63 mph the ice revved way high on three occasions. All freeway, all going downhill. The hill was quite steep and would not require the ice to run at all. If it were a standard 4 cry engine I would think it was past redline. Sure gets your attention. Stepped on the brake and it went away the did it twice more on this trip. Haven't driven on the freeway again. 1200 miles on the car when it went nuts. Didn't seem to hurt anything however.

When going downhill, the car will use regenerative braking for as long as possible. In this mode, the excess energy of going downhill is returned to the battery. Once the battery is full, it will spin up the engine, but use no gas. This is done to help keep speed as constant as possible. When you step on the brake, it uses the brake pads to absorb the downhill energy, and thus the engine slowed down. This is all entirely normal behavior. You most likely had the cruise control on - otherwise the car would simply go faster.

 

As Plus 3 noted, this is more common with downhill assist engaged. There is a switch on the shift lever that engages downhill assist. This causes the car to attempt to use a bit more regen during downhill operations. But it has no effect if the battery is fully charged. When engaged, there is a small yellow icon on the dash that looks like a car going downhill.

[rjam]

Thank you all! I am sure I had grade assist on since it was going from high mountain pass with a very steep grade and many miles long. Makes sense now!