ONE FOR THE TECHIES

[robiwill]

Hi just got a mk4 golf 1.6 AZD engine code and has an epc light with in a 15 seconds of the car running, then flashes up engine workshop.

code is 177961 Barometric/manifold pressure signals implausible correlation p1553 intermittent.

car has had new cambelt timing checked spot on, new egr valve.

the egr was replaced first and this first bought on the code as above. with the egr disconnected get eml light with egr fault but no epc

using live data checked signals and signal for barometric pressure was around 356 so changed map sensor this then gave correct readings when not running of 1010 when running it drops straight down to 350 again. Dont have another 1.6 gof in at present only a 20v turbo so checked the barometric readings on that and it stayed at 1012 running or just ignition on so assume this should be the case with the 1.6?

Temp sender showed no faults on live data but its ancient so could this be a cause as assume the ecu reads the engine temp from this sender.

I set the throttle body to basic settings and no difference

I have left the battery off for 12 hours and this didnt help.

The garage that fitted the new egr valve where this fault first appeared have stated that needs resetting by vw, having spoken to all the garages I use know one has heard of this before from fitting a replacement egr valve

I dont know if the garage casued this fault as the fault does not appear with the egr disconnected and the one that was replaced was knackered no dopubt as replacing it has never caused the egr fault codes to come back as it had 5 fault codes all egr and the egr was seized open.

so any ideas before I commit to a full loom check and then bba remain to check the ecu

[Bellend]

I have a customer with the exact same issue, eventually ran like sh!t with the EGR connected electronically but as soon as that plug was off it ran fine, even with the EGR blocked.

Eventually VAG-COM wouldn't connect and eventually the ECU died.

Second hand ECU and the car was flogged while it ran well.

[robiwill]

still stumped on this one, had same engine code car come in so swaped loads of bits over egr, throttle body, etc and still getting the fault code so unless anyone has any ideas or knows if the egr needs coding to the car which doesnt seem right as the problems car egr fitted to the new car doent bring on any fault codes so can only assume broken loom, drove it to a mechanics today and by time it got there in full saftey mode and no throttle at all just limped in. I am stumped.

[viperjsy]

may be a bad conection or brocken loom

[robiwill]

solved turned out to be a blocked cat building back pressure sorted one more mk4 ready to retail

[Bandit127]

Out of interest, how did you sort it?

Is there some magic solution that you can put in the petrol tank?

Italian tune up?

Or a new cat maybe..?