Ecu resetting itself !!

[Piggysniffer]

Ok guys, been off for a bit trying to sort out the issues with my car as per other posts, I've been throwing parts at, new maf, new o2, new electronic pedal assembly, second hand low miles throttle body, silicone boost pipes etc etc, I seem to have cured any sorts of vacuum or boost leaks, and the car runs beautifully..... but am still left with a random cutting out feeling, going into boost mostly, I have been data logging with romraider loads and have found that when this happens the ecu is actually resetting itself !! The IAM drops to .5 each time it happens and then goes immediately back up to 1 , also when I park the car up sometimes with all being perfect I will go to start the car and it has reset itself again, it cranks over for a few seconds exactly like a reset does before it starts, and the IAM is at .5 and once again goes immediately up to 1 as soon as its driven, I am now looking at either a bad earth to the ecu or positive, or a bad relay/s ???

ANY IDEAS GUYS ???

[Piggysniffer]

Ok guys im gonna have to put this over to another site or take it to a scooby place as I need to sort it

[stants]

Sorry mate been moving house, sounds like conflicting map /software, do you have twin maps ? In my experience the only time it tries to swap maps is when it looses power from the Battery or immobiliser kicks in,

Not familiar with the rom raider i'm afraid

[Piggysniffer]

It's all a bit confusing, lefts my mates house Thursday afternoon, had the long crank when starting, ecu had reset itself again, got the hump, ragged it outta the drive and up the road thinking its gotta learn boost and fuel trims and timing all over again, to my suprise I was getting 18.4 psi boost instead of the usual 14.7 from reset, and it ran like a champ for about ten miles, as I got near the gym it started messing about, checked the laptop, IAM had dropped to 0 ! With no massive knock events recorded, a -2.5 coming on boost on the fine knock correction, parked it up, came out of gym, reset ecu so it could relearn its IAM, it didn't move from 0 all the way home, about 6 miles, about a mile from home it went into limp mode and was hesitating like crazy, messed around moving knock sensor around to different bolt holes, no better, so reset ecu, wrapped knock sensor in a plastic bag while still connected and shoved it in a gap under the bpv, ordered a new sensor and am driving it sensibly, I have either got an electrical gremlin or some serious engine damage, engine sounds sweet tho, gonna run some extra grounds, remove ecu and clean all connections and fit new sensor and see what happens

[stants]

They would have heard or seen any potential damage or major knock when on the dyno the other month,

What alarm have you go installed ?

[Piggysniffer]

It wasn't me on the dyno mate, got a lazerline 996v3 on it, Spose it could be that ? Does have a receipt for recovery due to alarm fault in the history, will double check that, think it was ages ago, , I'm thinking that I have to be losing back up power to the ecu for it to reset, unless the knock sensor can trigger it, as you can see I'm chasing my tail a bit, just seems to runs so well when it's goin good that it's hard to imagine busted ring lands or anything 

[stants]

Ah thought it went on the rollers with engine tuner,

I'm thinking the same with not holding memory must be battery/charge related

[Piggysniffer]

Well I've put on new crank sensor, maf sensor, front o2 sensor, known good throttle body, new old stock electronic throttle pedal assembly, and have new knock sensor ordered, tbh at 98k it could do with all those sensors replacing anyway so that's OK by me, I think I would consider leak down and compression tests before I throw anymore parts at it tho, but I will do the knock sensor and some earths and the ecu plugs first, probs should trace the back up power feed and maybe replace it, just find it odd that it resets while driving when it's powered, unless it just actually drops the IAM to .5 and doesn't actually reset on the move 😖😳😁🙄😩😤😭💤