Hello, new to the forum but lots of great info on here. Looking for a direction to go as in diagnosing this weird power surge every start up. Vehicle came from other shops as they didn't want to touch or knew how hard it might be. Customer just wants check engine light out for reselling. Originally vehicle had lots of misfire faults, secondary air, boost control, and other various vacuum controlled system faults, replaced broken vacuum lines behind steering rack with Bentley parts, performed alignment and test drove. Only faults that returned was secondary air flow both banks, and P0321 engine speed (put in new sensor from Bentley) and power surge on start up, and fault 00084 in battery charger module. Disassembled vehicle and cleaned SAI pump filters, smoke tested all pressure tubes to Kombi valves, both pumps run and operate. Just wondering if this power surge is affecting the secondary air test? Re-smoke tested all vacuum and intake lines-ok. Checked all secondary air components per this forum. Also found left (house) battery not in good condition. Replaced per Bwings battery procedure in forum. But before disconnecting batteries found 80amp fuse on main fuse panel blown, replaced hoping that was it but no luck. Have checked fuses under cowl and by batteries but not the others yet, haven't looked up how to remove knee airbag yet. Batteries were replaced by others before me too.

 

short vid

 

some input or ideas would be helpful i will probably have to work on car again tomorrow. Was hoping to have some input from johnny hotspur or bwings, seemed like they know a lot from what I've read. maybe point out something cool like older secondary air threads and battery stuff. Surge also happened before i did any work.

 

Hello @Mienekemel ,
Welcome to 6speedonline !

As to your issues, I first took it as an engine surge of power, but now after watching your video, I see that it is an electrical surge occurring, besides the tach dipping down, the PRNDS also goes blank for a bit, I see an issue with the vehicle electric system battery switch over relay as "open circuit" as 00084, which is odd to me, as 00085 is in regards to the starter battery switch over relay, which I take as the parallel solenoid switch, so, does the parallel solenoid work when you turn the ignition key to the left and hold for 2-5 seconds, or do your hear the parallel solenoid engage when the issue occurs in the instrument cluster, remove the carpet panel to expose the starter battery for better ability to hear the solenoid, in a nice quiet area, I can hear mine from inside the vehicle with the windows up, it is a distinct clunk.

As to the 80 amp fuse that was blown, which 80 amp fuse was it, the 80 amp as shown in the picture you posted, mounted to the battery, or the one in the fuse box above the battery, as they are both listed as "F3" in their positions, but that is dependent on each panel/box location, the 80 amp "F3" fuse you pictured is for the LH/RH DOOR CM, both front seats CM's, and the power closing CM's, the 80 amp fuse in the fuse box above the battery in the "F3" position is actually for the "Battery management relay 2", so, let's clear this up, then the issue is, what caused a 80 amp fuse to blow, regardless of which one...

Johnny

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