E320 CDI - Intermittent No Kickdown & Power Loss

[Jonski]

Dear All,

My E320cdi automatic (w210 late 2000 with 90k miles) has an intermittent problem whereby :

- It won't kickdown, or even change down on the throttle.
- It seems to lack power in whatever gear I select manually.
- Seems unwilling to rev much over 2000 rpm.


I have clean the Mass Air Sensor, but to no effect, and changed the (very) dirty air filter. The problem is not normally evident when I first start the car, but after about 20 minutes driving something seems to happen in the auto-box which causes these problems.

I just wondered if anyone has had a similar problems. Any Ideas please? Thanks.
Jonski

PS. I read something about an oiled-up electricaly plug connector into the gearbox being the cause of various auto gearbox problems - could it be this?

 

[malcolm E53 AMG]

Hi,
Sounds very much like a G/B electroplate problem, symptoms very similar to my car when this component went down. As your car, initial symptoms were evident only after 30mins running, when car would attempt to set off in third/fourth gear and drop into limp mode (max revs 3000 and no kick down). Best to have codes read on STAR to confirm, cost in UK; electroplate £150, oil and filter change plus labour £300.

Eventually the car stuck in second gear permanently even after restart.

Hope this helps!

 

[toby1]

What Malcolm says - if it's stuck in a gear then probably electro plate thingy in the gearbox.

If you have all gears available but not kickdown, my fault was cured with a new MAS. I didn't bother cleaning it.

 

[HaydnM]

Could be a number of Faults.

1 / Throttle position Sensor ?

2 / Air Mass Fault ?

3 / Gearbox Electro Plate ?

 

[Jonski]

Reading the codes...

Thanks to all for your help and advice...

I have all the gears, just no kickdown, and it goes into 'limp' mode. Seems almost permanent now, it was intermittent before.

Since Mercedes are thinner on the ground here in France, I'd probably have to take it to the Merc dealer here to get the codes read. Does anyone know how much that would cost in the UK? I wonder would getting the codes read tell me definitively which of the 3 likely problems mentioned about is the fault?

 

[toby1]

Probably more than buying a new MAS from ECP with 25% discount and fitting it yourself. It's an easy job, though there is a risk it won't fix it. You have all the symptoms of it though. A quick search on this forum & you'll see how common they are

 

[television]

Try unplugging the MAF and try the car, we had a success with a smaller one tonight,, some do go better to prove the point but not all

 

[OlafMaxwell]

I had same problem and agree with Toby 1. MAF, its well known and the mileage is right for it to be the cause of your problem, and MB will charge you €75 plus VAt just for the diagnostic check. Better just change it.

 

[Steve@Avantgarde]

Or even a blocked/siezed EGR valve.....

You need a star diagnosis test before guessing at any of these faults.

 

[Jonski]

Try unplugging the MAF and try the car, we had a success with a smaller one tonight,, some do go better to prove the point but not all

Thanks. I tried unplugging the MAF, but it made no detectable difference to the performance either way (i.e. still in limp mode, acceleration levels/kickdown unchanged). I'm going to think about what to do next, based on the various comments above. I will report back in due course what happened. Thanks again to all....

 

[Jonski]

Testing the MAF Sensor Output Voltage

I found an excellent document on Benzworld (USA Merc Forum), that explains how to test the voltage output of the MAF. [I'd like to upload that document onto this site if someone would kindly tell me how to do that?]

I tested my MAF sensor and I found the following expected/actual results :

A. - Between pin 2 and vehicle earth - 12 Volts [supply voltage] (mine 12 Volts)
B. - Between pin 4 and pin 3 - 5 Volts [sensor voltage] (mine 5 Volts)
C. - Between pin 5 and pin 3 [ignition on] - 1 Volt +/- 0.02 volt (mine just over 1 Volt)
D. - Between pin 5 and pin 3 [at tickover] - 1.2 to 1.6 Volts (mine about 1.8 Volts)
E. - Between pin 5 and pin 3 [at ~3000-max rpm] - 3.3 to 4.4 Volts (mine about 3.3 Volts @ 3000 but intermittently jumping to 11.5 Volts!)

I hope E. above explains the problem I'm getting. At least, its enough for me to take a punt on the ~£50 for a new MAF sensor. My only doubt is whether it might be the plug thats faulty rather than the sensor itself, but I'll take a chance on that. Will report back whether it worked or not...

[PS. If anyone else wants to do the same test please note: I had to peel back the insulation expose a short section of the wires connecting to pin 3 and 5 to allow me to measure the 'output' voltage with the sensor connected up and engine running (Obviously, voltage measurements A. and B above can be done with the MAF plug pulled out as they are 'Input' voltages). Repaired the wires after with insulating tape. Also, watch out for the leads of the voltmeter and/or loose clothing getting anywhere near the fan when the engine is running - it struck me as a hazard when doing this test....]

 

[oigle]

I found an excellent document on Benzworld (USA Merc Forum), that explains how to test the voltage output of the MAF. [I'd like to upload that document onto this site if someone would kindly tell me how to do that?]

I tested my MAF sensor and I found the following expected/actual results :

A. - Between pin 2 and vehicle earth - 12 Volts [supply voltage] (mine 12 Volts)
B. - Between pin 4 and pin 3 - 5 Volts [sensor voltage] (mine 5 Volts)
C. - Between pin 5 and pin 3 [ignition on] - 1 Volt +/- 0.02 volt (mine just over 1 Volt)
D. - Between pin 5 and pin 3 [at tickover] - 1.2 to 1.6 Volts (mine about 1.8 Volts)
E. - Between pin 5 and pin 3 [at ~3000-max rpm] - 3.3 to 4.4 Volts (mine about 3.3 Volts @ 3000 but intermittently jumping to 11.5 Volts!)

I hope E. above explains the problem I'm getting. At least, its enough for me to take a punt on the ~£50 for a new MAF sensor. My only doubt is whether it might be the plug thats faulty rather than the sensor itself, but I'll take a chance on that. Will report back whether it worked or not...

[PS. If anyone else wants to do the same test please note: I had to peel back the insulation expose a short section of the wires connecting to pin 3 and 5 to allow me to measure the 'output' voltage with the sensor connected up and engine running (Obviously, voltage measurements A. and B above can be done with the MAF plug pulled out as they are 'Input' voltages). Repaired the wires after with insulating tape. Also, watch out for the leads of the voltmeter and/or loose clothing getting anywhere near the fan when the engine is running - it struck me as a hazard when doing this test....]

If the article from the other forum is in one post, why not just copy and paste in into a new thread here? Otherwise, posting the link to the document would also work.

 

[Jonski]

Thanks, but I have the pdf document downloaded on my computer. I can't locate it anymore on Benzworld, so I can't paste the link. Is there any way I can upload the copy I've got?

 

[Zenshin]

Hi,

I've got the same problem on 04 E270. Started on Monday going to work, just as previously stated, after 20 minutes or so, there's no power low down, I have all gears, but no kickdown. Went away when I started the car at lunchtime, and was fine until this morning when it went again.

Is it the general consensus that it's the MAF.

I plan to take it to my local specialist for them to look on STAR, but thought I'd try and get a heads up first, I've only had the car 2 months, and am hoping I may be able to get the garage I bought it from (not an MB dealer) to pay for it.

 

[Jonski]

I ordered a new MAF yesterday, should get it within a few days, then I'll report back if the problem is fixed....

 

[Zenshin]

I spoke to the dealer who sold my car to me, and he's arranged for me to go to local specialist so he can look on STAR and see if it explains anything, I too shall report back.

I also noticed on my way home tonight, that I seem to be getting large amounts of black smoke, when accelerating hard - assuming that I'm not suffering from the whole no kickdown issue. Don't know if this is also a symptom of EGR problems, which I've read elsewhere can also cause power loss?

I also wondered if I'm seeing this fault now, potentially, as the weather gets cooler, certainly this morning was cooler than of late and I think it was on Monday as well, the first time I experienced this,, and I haven't had the problem in the evening - could this be down to the air being denser? affecting the MAF?

 

[Steve@Avantgarde]

Who is the specialist in Bristol you are using?

 

[oigle]

I spoke to the dealer who sold my car to me, and he's arranged for me to go to local specialist so he can look on STAR and see if it explains anything, I too shall report back.

I also noticed on my way home tonight, that I seem to be getting large amounts of black smoke, when accelerating hard - assuming that I'm not suffering from the whole no kickdown issue. Don't know if this is also a symptom of EGR problems, which I've read elsewhere can also cause power loss?

I also wondered if I'm seeing this fault now, potentially, as the weather gets cooler, certainly this morning was cooler than of late and I think it was on Monday as well, the first time I experienced this,, and I haven't had the problem in the evening - could this be down to the air being denser? affecting the MAF?

Absolutely correct. EGR sysmptoms and MAF symptoms are very similar in the limp mode area. The black smoke would indicate EGR as the more probable culprit.

 

[Zenshin]

Who is the specialist in Bristol you are using?

RS Auto services in Warmley. Previously I've used Threepoint, but RS is the garage that is used by the dealer I bought the car from, and as I'm hoping to get any work done on the warranty, I'm going there first.

Out of interest, the cold is not the instigator, this morning was the coldest morning so far, and i didn't have any problems with kickdown, but I noticed more smoke, even when accelerating quite gently at times. Also, I've noticed that my fuel economy is dropping, on a good run in the past I've managed 36 mpg, this morning, despite driving carefully (with the odd kickdown to check if the problem had returned) I only got 28 mpg. Is this all pointing to a bigger problem???

 

[toby1]

RS Auto services in Warmley. Previously I've used Threepoint, but RS is the garage that is used by the dealer I bought the car from, and as I'm hoping to get any work done on the warranty, I'm going there first.

Out of interest, the cold is not the instigator, this morning was the coldest morning so far, and i didn't have any problems with kickdown, but I noticed more smoke, even when accelerating quite gently at times. Also, I've noticed that my fuel economy is dropping, on a good run in the past I've managed 36 mpg, this morning, despite driving carefully (with the odd kickdown to check if the problem had returned) I only got 28 mpg. Is this all pointing to a bigger problem???

I'd be interested to hear about your fuel consumption issues and the eventual outcome. Keep us posted please.