[virtual_law]

So, my car is bone stock, and recently just had the DME+fuel filter+solenoids replaced at the workshop. Car stands at 50k miles.

It still has intermittent stuttering now and then but sometimes idles fairly smooth.

However, my issue is with WOT when the car is fully warmed up nearing 120 degrees oil temp. When I give it the beans (WOT), it immediately starts misfiring and as rpms drop back to idle, it becomes rough as if one or two cylinders are off but gives no check engine light. It then starts idling rough. Shut the car off, and back on, and it smoothens out again and drives normal until next WOT.

Active Codes:
29DC: Cylinder injection cutout
2A2D: fuel low-pressure system, fuel pressure.
2AAF: fuel pump, plausibility.

Shadow Codes:
2FCA: fuel high pressure bei freigabe der einspritzung
2FDA: crankshaft sensor, signal: Missing

From all the forum reading, it seems like a fuel issue, pointing towards LPFP, low fuel pressure sensor or HPFP. Those 3 are original to the car. Before I start throwing parts at it, I connected ISTA to read fuel readings after a 30 min drive with some 4500 - 5000 rpms burst thrown into the mix. I waited 15 mins and with the engine off, I got very low Hpa readings.

Low fuel pressure reading: 1729 hpa
High fuel pressure reading: 2085 hpa

Both of these values were dropping down fairly quickly also while I was connected to DME.

I know data logging is the preferred method for diagnosing lpfp or hpfp and cylinder injection cutout issues, but I do not have the MHD license purchased yet and don't know how to log with INPA or ISTA.

Can any conclusions be drawn from the above? Attaching pics of the fuel pressures.

[virtual_law]

A follow up:

I've replaced the low pressure fuel pump, and my idle pressures are back in spec, showing 5000 hpa at idle. However, it did not affect running much. I suspect the little misfire feeling at idle (no codes) is down to something else.

Edit: After replacing lpfp, I did a couple of WOT at operating temperature. It threw a half-engine light, and couple of Vanos exhaust codes. I cleaned the exhaust Vanos, and cleared the codes. Drove it around a little, went WOT once, and didnt get another light. The car doesn't feel perfect still, with little misfires at idle that I can certainly feel, some pops in exhaust now and then, but no codes.

I'd say the problem is semi-fixed.

[ILoveAndHateN54]

You got Snapchat or Instagram? I want to chat with you about this but I don’t check this forums much.

[virtual_law]

Originally Posted by ILoveAndHateN54

You got Snapchat or Instagram? I want to chat with you about this but I don’t check this forums much.

haha sure. Same ID as my username here. The profile pic would be me with my face cut off. Edited my above 'follow up' btw.

[thisizaremix]

Did you resolve your issues?