CL500 W215 Diagnostic Results: Missfires and Throttle Valve Angle

[CL500Wizard]

Hiya

Had a full MBSTAR diagnostic carried out today and the results as follows:


1st Issue
TEST VALUES AT IDLE SPEED
No: 009
Name: Throttle Valve Angle
Specified Value: [0.3...2.5]
Actual Value: 3.5
Unit: Grad DK

Indie is suggesting removal of the unit, a clean and reprogram before re-install.


2nd Issue
SMOOTH ENGINE RUNNING
No: 065
Unit: 1/sec**2
Specified Value: [0.00...1.00]
Actual Value:
CYL1 0.00
CYL5 0.00
CYL4 0.00
CYL2 2.81
CYL6 2.05
CYL3 0.00
CYL7 -0.26
CYL8 -0.51


Indie is suggesting that it is either the spark plugs or the HT leads on cylinders 2,6,7 & 8 but definitely not the Coils - recomending change of all plugs and HT leads


I had suspected the leads & plugs so got a quote for Bosch platinum plugs and TDC HT Leads from ECP. Plugs should be fine as the last Indie who carried out a major B service said the platinum plugs were replaced at 65K (mileage now is 96K) so I think it should be the HT leads and not the plugs considering some cylinders are firing perfect. I plan to source and change all the leads myself. any hints/tips please?

As for the Throttle Valve Angle, I had spoken with the Indie (who carried out the diagnostic today) a few weeks back over the phone and he had suggested then that it is most likely the plugs, leads or TVA causing the misfiring/vibrations and high fuel consumption, and I have to say he was pretty spot on with the results today!

2 Questions on TVA:
i. Does it need special hardware/software to program it back to within its tolerance values?
ii. Is it difficult to remove and where is it located (my guess would be below the MAF)?


Car is off road until this is fixed as I don't want to kill the cats and so that I can take my time doing this myself as long as there is a guide somewhere or someone can be really kind enough to write one on this TVA issue.


Lastly, one issue which I totally forgot to ask to be checked (work on mind then) ... the Engine Temp guage has started creeping up above 80 in traffic, max it has reached is 100. It started doing this only past few days and I do not hear the fan kicking in at all - where do I start?


A lot of questions so really appreciate your time and input.

Many thanks
Arslan


p.s. I had cleaned the MAF a few weeks ago with elec contact cleaner and it is reading 16kg/h which is within the range of 12..20 - phew!

 

[CL500Wizard]

anyone with comments?

 

[television]

Later in the day

 

[CL500Wizard]

Malcom, can you please confirm if the Cylinders are as follows if standing in front of the bonnet:

7 ----- 8
5 ----- 6
3 ----- 4
1 ----- 2
<Standing Here>


I want to remove the plugs on #2 to see the condition, just incase they are fouled and need replacing. I have the leads but didnt buy the plugs until checking the condition on at least one cylinder.

found this guide http://cryptiksouls.co.uk/mercedes/plugs/index.html from one of the 200 links you posted is useful, so thank you - just don't have the long 17mm spanner but will improvise!

Thanks

 

[television]

Malcom, can you please confirm if the Cylinders are as follows if standing in front of the bonnet:

7 ----- 8
5 ----- 6
3 ----- 4
1 ----- 2
<Standing Here>


I want to remove the plugs on #2 to see the condition, just incase they are fouled and need replacing. I have the leads but didnt buy the plugs until checking the condition on at least one cylinder.

found this guide http://cryptiksouls.co.uk/mercedes/plugs/index.html from one of the 200 links you posted is useful, so thank you - just don't have the long 17mm spanner but will improvise!

Thanks

I have not got a clue on the cylinder numbers, but it look right on your diagram.

Any spanner that fits can be used to lever off the caps,but to buy a cheap one is only a couple of ££

 

[CL500Wizard]

I have a few 17s knocking about.

I've searched a lot to find any guide on TB removal and clean for the M113 engine but no luck so far. Looked at http://www.detali.ru/cat/oem_mb2.as...GA=722.633&CT=M&cat=07N&SID=14&SGR=030&SGN=01 but it looks nothing like what it should be considering the MAF sensor is horizontal in this diagram and on the car it is vertical.

Search continues, let's see how I get on with the lead changes today. airfilter housing has to come off anyway so will see if I can see the TB under the MAF.

 

[television]

We have another car doing the same,,just so that we can link them

http://forums.mercedesclub.org.uk/showthread.php?t=50077

 

[Cole@MBS]

Ones a v8 Malc the other is a v12.

 

[television]

Ones a v8 Malc the other is a v12.

OK I will go back to bed :Oops:

 

[Cole@MBS]

OK I will go back to bed :Oops:

Just thought i would point that fact out! Sorry Malc

 

[television]

Just thought i would point that fact out! Sorry Malc

Whats 4 cylinders among friends

 

[CL500Wizard]

Just seen the pics on Sam's site and I really hope its not oil starvation on one or 4 of those cylinders.

dinner time and then will investigate. I really hope its an easy fix as replacing leads (&/or plugs). Should I clean lead contacts in the coil with the electronic contact cleaner - just incase?

 

[CL500Wizard]

oh ......... with Tesco 99 fuel, the misfire is a lot less compared to on regular 95 fuel. I wonder if reacting to different fuel directs to something?

 

[CL500Wizard]

Opened up it all up, checked the plugs (NGK Platinums in there!) and they were in good shape. replaced all the leads and miss-firing has cured completely. Very very light engine vibrations at idle are there, likely due to throttle valve out of spec but no more vibrations during driving and the car revs and sounds completely different - been for a 100 miles drive (slow and fast) and all perfect

for reference:

Cylinders:
4 --- 8
3 --- 7
2 --- 6
1 --- 5
<standing in front of the engine>

so 3 foul leads on the right side, and 1 on the left.


next to do on the list:

1. Throttle clean and TVA adjustment
2. Replace left hand side rocker cover gasket as its leaking a bit of oil
3. Gearbox filter and oil change


Happy with the results - just these bits to do and it should be good for another good few K miles.

 

[Manc]

Hi, Yeah 2 cylinders show up faulty on the Merc diagnostics recently.
Coils or coil control center didn't fix it either

 

[Manc]

Hi CL500,
So what fixed your misfire then? just the plugs and leads?

 

[CL500Wizard]

Hi CL500,
So what fixed your misfire then? just the plugs and leads?

The leads only. Checked the condition of all spark plugs on miss-firing cylinders just incase any were fouled but all were ok. If you want to make sure it is the leads before purchasing, take lead 'a' from a good cylinder and 'a' from a bad one and check resistance with voltmeter and then do the same with 'b' leads. I'm not sure what standard resistance should be for our cars but variance will tell you if the miss-firing cylinder leads are faulty.

I'm not sure if you can source a set of 2 leads per cylinder individually (I think it is possible from MB only) but I replaced the full set with aftermarket TDC leads.

HTH




I'm still pending someone to guide me on TB removal and Throttle Valve Adjustment .... surely its been done by some of the techies here before - so someone please comment.