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-   -   2008 E320 Bluetec Harsh Gear Shift (http://www.peachparts.com/shopforum/diesel-discussion/395598-2008-e320-bluetec-harsh-gear-shift.html)

nyko46 10-21-2018 07:36 PM

2008 E320 Bluetec Harsh Gear Shift
 
My 2008 Mercedes Benz E320 Bluetec with 97K miles is giving me a NOT happy harsh down gear shift and also up gear shift specially when reducing speed just before stop in a traffic light and just after taking off from traffic light.
This harsh gear shift makes no noise but cause the car to jump back and forward when it happens. The engine light came on just before it started to be noticed. Also from time to time the engine's RPM does not increase when the accelerator is pressed down as it was before.
About engine RPM this week I had time when it responded to the accelerator and in the same week times when it did not responded to the accelerator.
I have the car not yet scanned for the engine light due the work schedule but I will have it done today, Friday 10/19/18.
Driving to and from work, a trip of 27 miles each way in a highway, I have no problem with speed or gear shifting. All run normal, no noise, nothing noticeable except engine RPM when, in purpose, I press hard the accelerator.
About gear shift I have read couple cases on the Internet but did not find anything about Diesel engines. All of them are about Gasoline engines which, I believe, have different transmission. If I am no wrong this car has a 6 speed automatic transmission.
I will be glad having your input and suggestion about this issue.
I will also update this thread after having the car scanned.
UPDATE: Auto Zone scanner gave me two codes: P-0471 and P-2015
P0471: Exhaust Pressure Sensor Range/Performance
P2015: Intake Manifold Runner Position Sensor/Switch Circuit Range/Performance Bank 1
Also, if it helps, the last job performed on this car was a fuel filter replacement in which a removal of the air intake ducts are necessary.
Does it have something related with the issues on this car?
Thanks for your reply.

sixto 10-21-2018 08:23 PM

Check the transmission fluid level or have it checked. I’m pretty sure it’s a 722.9 7-speed automatic.

Sixto
98 E320s sedan and wagon
02 C320 wagon

nyko46 10-21-2018 08:30 PM

About be 6 or 7 speed, the + and - signs at the transmission lever show up to number 6 when moving to +. Does it say anything about number of gears? Thanks

sixto 10-22-2018 02:11 AM

It will go from 1 to 6 then to D. That’s 7 forward speeds.

Sixto
98 E320s sedan and wagon
02 C320 wagon

engatwork 10-22-2018 06:11 AM

Any maintenance history on it? I've seen shift quality change for the worse when the wrong fluid was used.

jay_bob 10-22-2018 10:36 AM

We have the same car, and I also have a ML320 of the same year with the same engine and transmission. And a 2014 ML350 with the later versions of the OM642 and 722.9.

You have the first generation 7 speed 722.9 transmission. This does take special ATF. Note there are two fluids for the 722.9, you have the earlier model that takes the special "red" fluid not the special "blue" fluid.

P2015 I am reasonably sure that is your swirl flap motor. Temporarily do this to see if this is your problem. Find the swirl flap motor, it is just behind and below the fuel filter. You will probably have to remove the intake Y-pipe to see it. It is a black box that is sitting in the V. Follow the cable from the motor to a 4 pin connector in the neighborhood of the fuel filter. Unplug the connector and on the vehicle side of the plug take a 4.7 k ohm resistor, bend the leads and stick into the two center pin sockets. Cover with electrical tape to ensure no shorts. See if that clears your light, if so, your swirl flap motor is shot. Don't leave it like this, your bad performance will continue until it's fixed.

P0471 up under the car you will see the DPF. There are several sensors screwed into the pipe with electrical cables, these are oxygen and temperature sensors. You will also see two 1/4 inch tubes coming off the DPF, that transition to rubber lines, and go to a sensor box mounted somewhere out of the way (on the E320 I haven't been looking down there, I know where it is on the ML) under the car above the filter. This is your exhaust pressure sensor. It looks at the difference in pressure across the DPF to know when to regen and also if it is getting clogged. I am pretty sure this is the sensor they are talking about, when I took apart the ML to change the oil cooler seals I had to remove the exhaust leader from the turbo to the cat and there are no other pressure sensors upstream of the DPF.

Xentry is your friend with these cars. Best money I ever spent (for a bootleg on eBay) having 4 computer controlled diesels, it has paid for itself many times over. Not only does it tell you exactly what the problem is, the error log is hyperlinked right to the procedure to fix it.

I can also recommend once you get these 2 issues sorted then have a visit to the dealer, pay for an hour of shop time, and have them do the ECU and VGS firmware updates that are out there for the 642 and 722.9. Makes a huge difference in the upshift/downshift behavior. Unfortunately you can't do these with a bootleg computer since it has to authenticate to Germany to load firmware.

Also have them clean out all the cobwebs in the fault history (these things store an event if you fart in the seat) so you have a baseline. These won't show up on generic OBDII scanners.

nyko46 10-22-2018 08:11 PM

I have this car for only 6 months and the historic that I have is the oil change.
The only thing that I did was change the fuel filter. Filter only not the water level sensor.
There are Mercedes mechanics that say that the water level sensor on top of the fuel filter MUST be replaced when changing fuel filter otherwise it causes problems similar to this one.

nyko46 11-02-2018 11:45 AM

Harsh Transmission Shift Issue Resolved
 
About the posted issue with harsh transmission shift and no acceleration I had to bring the car to a specialized and fully equipped Mercedes Benz shop.
They diagnosed the car and found 18 old codes and 2 new codes and from there they worked to resolve the problem that was going on: no acceleration and transmission harsh gear shifting.
The diagnostic showed a NOT working Intake Manifold Actuator.
They disassembled everything including a removal of the turbo in order to get access to this part and had it replaced for a OEM part.
They reassembled using new o rings, gaskets, and other parts all OEM parts.
Mechanic told me that the harsh shift was related with manifold not working at all and consequentially confusing the computer when to shift and when not to shift. After repair the car worked fantastically getting back acceleration and engine power. Transmission works very good in all gears no having anymore harsh shifts.
"Technically speaking" he said " it was an electronic issue because air intake manifold is a electric device controlled by the car computer".
In TEXAS the total cost of the repair was $ 1160.00 with parts, labor and taxes. The parts only was $ 450.00 for OEM parts and the remaining for labor and taxes. They give a one year or 12 months warranty.
I thank everyone that sent me a reply related to this issue. It was very appreciated.
Believing that it can help someone I decided to post how issue was resolved.

gsxr 11-02-2018 01:25 PM

Glad to hear your shifting issue is resolved! That's good news.

However... if the fluid & filter has never been changed (or, you have no record of it).... I'd highly recommend that with 100kmi on the clock. These transmissions are not "filled for life". The "special" ATF is not that special, it's 236.14 spec, and Red Line D6 works just fine. Newer models that require the blue 236.15 fluid are a different story.

:balloon2:

nyko46 11-03-2018 10:42 PM

Thanks for your recommendation about the ATF change.
I think this was a very good tip.


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