Strange problem
#1
Junior Member
Thread Starter
Join Date: Mar 2014
Posts: 29
Likes: 0
Received 0 Likes
on
0 Posts
Slk 32 Amg
Strange problem
Hello,
Is' m gonna explain you the problem I have on my SLK 32 AMG.
I hope finding some advices or solutions to my problem.
My mods are : NW intercooler, tweaked manis, 181 EC pulleys, downpipe, DCAI, Oil catch, 255 walbro kit with the OEM pressure regulator.
I have changed as parts : sparks and wires, ignition coils, IAT sensor, MAP sensor, CPS.
The car is very fun to drive until 5400 rpm (390 engine hp). After that, I lost all my power (310 engine hp). ALWAYS AT THE SAME REV.
You will attached the dyno.
Also, I have obtained the logs from my tuners and the conclusion is :
-Air pressure is correct to the red line
-Timing ignition is also correct
-Air flow (which is a calculation based on the throttle body position) looks like exact the same curve like the power. i think it is not normal and maybe it is the main problem, right?
You will also find the logs datas.
Another thing very strange is that the problem occurs at 5500rpm (the same rev like winter mode on the automatic transmission).
What is the cause of this problem?
1) Problem with the TCU?
2) No enough fuel (lean condition) / AFR problem? My tuner has injected more than 10 maps with more fuel without any positive effects...
3) Problem with the TPS? Pedal assembly?
4) Another issue?
Thanks for your help because investigations make me crazy...
Julio
Is' m gonna explain you the problem I have on my SLK 32 AMG.
I hope finding some advices or solutions to my problem.
My mods are : NW intercooler, tweaked manis, 181 EC pulleys, downpipe, DCAI, Oil catch, 255 walbro kit with the OEM pressure regulator.
I have changed as parts : sparks and wires, ignition coils, IAT sensor, MAP sensor, CPS.
The car is very fun to drive until 5400 rpm (390 engine hp). After that, I lost all my power (310 engine hp). ALWAYS AT THE SAME REV.
You will attached the dyno.
Also, I have obtained the logs from my tuners and the conclusion is :
-Air pressure is correct to the red line
-Timing ignition is also correct
-Air flow (which is a calculation based on the throttle body position) looks like exact the same curve like the power. i think it is not normal and maybe it is the main problem, right?
You will also find the logs datas.
Another thing very strange is that the problem occurs at 5500rpm (the same rev like winter mode on the automatic transmission).
What is the cause of this problem?
1) Problem with the TCU?
2) No enough fuel (lean condition) / AFR problem? My tuner has injected more than 10 maps with more fuel without any positive effects...
3) Problem with the TPS? Pedal assembly?
4) Another issue?
Thanks for your help because investigations make me crazy...
Julio
Last edited by Julio77270; 07-15-2014 at 12:15 PM.
#3
Member
Join Date: Mar 2005
Location: Sweden
Posts: 94
Likes: 0
Received 0 Likes
on
0 Posts
SLK32 AMG
Hi Julio
Have you Checked IAT and AFR value ?
I have a SL55 amg Fuel pump and no pressure regulator. That fuel pump can handle a lot. About 800 hp and more.
I know that our cars i at max load at 5400 rpm - 5800 rpm. But i dont think that is the problem.
Lets see what your IAT and AFR value is.
It could be in the restriction in the TCU and the Gearbox. You only get 60 % of the power from the engine original to the wheel.
Regards Göran
Have you Checked IAT and AFR value ?
I have a SL55 amg Fuel pump and no pressure regulator. That fuel pump can handle a lot. About 800 hp and more.
I know that our cars i at max load at 5400 rpm - 5800 rpm. But i dont think that is the problem.
Lets see what your IAT and AFR value is.
It could be in the restriction in the TCU and the Gearbox. You only get 60 % of the power from the engine original to the wheel.
Regards Göran
Last edited by Guran; 07-15-2014 at 07:01 PM.
#4
Junior Member
Thread Starter
Join Date: Mar 2014
Posts: 29
Likes: 0
Received 0 Likes
on
0 Posts
Slk 32 Amg
Thank you Guran for your answer!
My IAT are very good around ~30°C more than the ambient temperature.
I haven't yet diagnosed the AFR.
But I have a 255 walbro fuel pump kit installed on my car with the standard pressure regulator. Maybe it is the main problem ?
Do you have a standard pressure regulator or none regulator on your car?
What is the restriction in the TCU ? I need to remove the load restriction ?
Thanks,
Julio
My IAT are very good around ~30°C more than the ambient temperature.
I haven't yet diagnosed the AFR.
But I have a 255 walbro fuel pump kit installed on my car with the standard pressure regulator. Maybe it is the main problem ?
Do you have a standard pressure regulator or none regulator on your car?
What is the restriction in the TCU ? I need to remove the load restriction ?
Thanks,
Julio
#5
Member
Join Date: Mar 2005
Location: Sweden
Posts: 94
Likes: 0
Received 0 Likes
on
0 Posts
SLK32 AMG
TPS
Thank you Guran for your answer!
My IAT are very good around ~30°C more than the ambient temperature.
I haven't yet diagnosed the AFR.
But I have a 255 walbro fuel pump kit installed on my car with the standard pressure regulator. Maybe it is the main problem ?
Do you have a standard pressure regulator or none regulator on your car?
What is the restriction in the TCU ? I need to remove the load restriction ?
Thanks,
Julio
My IAT are very good around ~30°C more than the ambient temperature.
I haven't yet diagnosed the AFR.
But I have a 255 walbro fuel pump kit installed on my car with the standard pressure regulator. Maybe it is the main problem ?
Do you have a standard pressure regulator or none regulator on your car?
What is the restriction in the TCU ? I need to remove the load restriction ?
Thanks,
Julio
If the TPS is closing is must be the TCU or ECU. Can you read the TPS in your logg. Probably you have to increase your Torque limiter.
I have removed all limits.
Your Fuelinjectors is to small ?
Lets find out the AFR value
Last edited by Guran; 07-16-2014 at 07:01 PM.
#6
Junior Member
Thread Starter
Join Date: Mar 2014
Posts: 29
Likes: 0
Received 0 Likes
on
0 Posts
Slk 32 Amg
I have a standard fuelfilter with 3,8 bar regulator and a SL55 AMG fuel pump.
If the TPS is closing is must be the TCU or ECU. Can you read the TPS in your logg. Probably you have to increase your Torque limiter.
I have removed all limits.
Your Fuelinjectors is to small ?
Lets find out the AFR value
If the TPS is closing is must be the TCU or ECU. Can you read the TPS in your logg. Probably you have to increase your Torque limiter.
I have removed all limits.
Your Fuelinjectors is to small ?
Lets find out the AFR value
My tuner is looking for on this way.
Concerning my fuel injector, I have the OEM ones and I have planned to installed a variable fuel regulator
#7
Junior Member
Thread Starter
Join Date: Mar 2014
Posts: 29
Likes: 0
Received 0 Likes
on
0 Posts
Slk 32 Amg
The problem on my car comes from an air mass flow issue.
How is calculated the air mass flow in our car?
I guess with IAT, MAP, throttle body sensor. Is it right?
How is calculated the air mass flow in our car?
I guess with IAT, MAP, throttle body sensor. Is it right?
Trending Topics
#9
Member
Join Date: Mar 2005
Location: Sweden
Posts: 94
Likes: 0
Received 0 Likes
on
0 Posts
SLK32 AMG
I have had same problem when the pressure is at top.
New gasket and form a gasket 3 glue. Works for me
Last edited by Guran; 02-23-2015 at 04:54 PM.
#10
Junior Member
Thread Starter
Join Date: Mar 2014
Posts: 29
Likes: 0
Received 0 Likes
on
0 Posts
Slk 32 Amg
I have checked all the gasket and replaced them by new ones without any good effects.
It sound like a mass air flow issue.
How it is calculed?
By AT sensor.
1) Maybe it is bad. I have changed it twice.
2) water pump is going bad?
by Map sensor :
1) what is the best reference to have ?
By throttle body sensor or pedal assembly?
Thank you for your help
Julio
It sound like a mass air flow issue.
How it is calculed?
By AT sensor.
1) Maybe it is bad. I have changed it twice.
2) water pump is going bad?
by Map sensor :
1) what is the best reference to have ?
By throttle body sensor or pedal assembly?
Thank you for your help
Julio