P1999 P20D4 Load Limit is active
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Joined: Jul 2005
Posts: 3,164
Likes: 19
From: London, UK
No longer stock '06 E55, A3 3.2 Quattro, GLE 400d, R107 280SL, Golf Polo
P1999 P20D4 Load Limit is active
I've tried everything to shake this code but it keeps coming back.
I've searched everywhere replaced a bunch of parts and still it comes back.
I first saw it when I was fooling around with Aquamist Meth Injection and its kind of stuck with me since. I am wondering if the harness got messed up when doing this but I've gone through every section and looks fine. Need to recheck ground points maybe.
Car has pretty every mod you can throw at it but any ideas on how to resolve would be great.
Car has Wetterauer tune
Carbonio Air Box
83mm TB (new) - had 80mm before and trying this.
Kleemann cams and shorty header
TCU tune for 2.82 diff with Quaife
180mm Crank Pulley
See around 14psi max boost
Vacuum hits -11.4Psi
New Injectors, New coils, New HT leads, New Plugs
Resealed S/C with new gaskets
Code comes active and I don't get a check engine but do feel a dip in performance (slightly) - but ignition timing looks like it gets retarded and plugs get fouled / runs rich etc. rinse repeat.
Killing me.
Timing is often -20deg to -12 at startup which is much more retarded than what the Autel says is in tolerance.
Using Autel to get the codes and trying to get a DAS setup to get better details but the one I got is not working as expected!
Any thoughts / help let me know pls. And yes I have STFF - all of them.
I've searched everywhere replaced a bunch of parts and still it comes back.
I first saw it when I was fooling around with Aquamist Meth Injection and its kind of stuck with me since. I am wondering if the harness got messed up when doing this but I've gone through every section and looks fine. Need to recheck ground points maybe.
Car has pretty every mod you can throw at it but any ideas on how to resolve would be great.
Car has Wetterauer tune
Carbonio Air Box
83mm TB (new) - had 80mm before and trying this.
Kleemann cams and shorty header
TCU tune for 2.82 diff with Quaife
180mm Crank Pulley
See around 14psi max boost
Vacuum hits -11.4Psi
New Injectors, New coils, New HT leads, New Plugs
Resealed S/C with new gaskets
Code comes active and I don't get a check engine but do feel a dip in performance (slightly) - but ignition timing looks like it gets retarded and plugs get fouled / runs rich etc. rinse repeat.
Killing me.
Timing is often -20deg to -12 at startup which is much more retarded than what the Autel says is in tolerance.
Using Autel to get the codes and trying to get a DAS setup to get better details but the one I got is not working as expected!
Any thoughts / help let me know pls. And yes I have STFF - all of them.
Last edited by stevebez; Jan 12, 2026 at 07:42 AM.
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Joined: Jan 2026
Posts: 14
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From: İstanbul
W220 s500 w215 cl55 w639 viano w218 cls350
Has the ecu adjustment been made after the upgrades? I had a lot of problems with the same code and the problem was due to the pulley I reduced by 6 mm, I set it from 82 to 76
