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I've got a stage 2 amr tune tune worked great until I had cams replaced by mercedes. Now when I flash the tune , upon acceleration it falls on its face stalls and I get this code. Can not find anything about diagnostic procedure or specs for the high pressure system anyone know or have these please??
I've got a stage 2 amr tune tune worked great until I had cams replaced by mercedes.
Now when I flash the tune , upon acceleration it falls on its face stalls and I get this code.
Can not find anything about diagnostic procedure or specs for the high pressure system anyone know or have these please??
i am not a tune dude.... but use a scanner to read your fuel pressures, both low + high sides.
Then set your instrument cluster to display voltage, how low does it get during acceleration?
I've got a stage 2 amr tune tune worked great until I had cams replaced by mercedes. Now when I flash the tune , upon acceleration it falls on its face stalls and I get this code. Can not find anything about diagnostic procedure or specs for the high pressure system anyone know or have these please??
high side drops from 2500 to around 1500 not sure about low side and my system never falls below 14.4 volts
high side drops from 2500 to around 1500 not sure about low side and my system never falls below 14.4 volts
Great, so your issue is may be with fuel only.
> Low Pressures:
Pressure dropping 1000psi is exactly what's causing lean acceleration instead of rich!
Read the low pressure pump module output pressure - It supplies HPFP with volume.
What's total mileage?
> Voltage control:
14.4V during acceleration...
your ECU does not do smart charging or it's disabled??
I'd expect 13.7V under accelerations or less if faulty
Last edited by CaliBenzDriver; 10-28-2023 at 06:20 PM.
Reason: voltage ECU bug
It worked fine before . Mercedes just replaced the intake cams (phasers shifted). It sat there for 2 1/2 months . I'm not getting the code or problem with the stock tune only when I swap back to the stage 2 tune. Milage is 119k. I was thinking something was not installed correctly post hp pump. I think it ran better when it thought it was out of time.
I can not display voltage on cluster but readings from bass knob on aftermarket ampwhich 9_10 matches scan tool data. I've seen it drop 13.5 on deceleration. Not sure if smart charge is active I've got a snap solus and identifix. I can not find specs for fuel system online or identifix .
It worked fine before . Mercedes just replaced the intake cams (phasers shifted). It sat there for 2 1/2 months . I'm not getting the code or problem with the stock tune only when I swap back to the stage 2 tune. Milage is 119k. I was thinking something was not installed correctly post hp pump. I think it ran better when it thought it was out of time.
I didn't want to blame the guy who swapped your camshaft up front...
but HPFP has an assembly procedure to prevent pump damages.
I think they nailed your pump... and that's what you need now with new roller along with a PCV Kit (right near HPFP) and your tank fuel filter is due.
> Alternator :
At 120kMi... you're good for a brushset or new alternator if not replaced at time of audio upgrades.
Dynamic ALT output is remotely managed by ECU as follows:
Deceleration may go UP to 14.9V
Acceleration goes DOWN to 13.7V
(Network chaos may drain to 11.V)
Observing good voltage with these cars, is not enough when they keep eating batteries.
Top chart is stock closest to fuel demand ..
Middle is tuned
Bottom is stock
this is the closest i could come up with that was comparable .
It seems as if its just wanting the hp pump to work quicker then it is??