[7 Seat Sports Car]

Hi all,

My ME7 V70 T5 is running rich all the time and I'm looking for some advice on what else I can check as it's going to fail it's MOT on emissions and if so it's getting crushed! I'm at my wits end.

I've gone through Vida and looked at resistance and voltage figures for both O², MAF, ECT, IAT, MAP, PTC TCV and evap purge. I cannot find anything wrong or out of spec. I've had all the induction pipes and intercooler as well as intake manifold and throttle body off and checked for leaks, nothing. I've double checked all the vacuum hoses, again, fine. I've had the exhaust off and found a few pinholes in the work experience welds on the aftermarket replacement Cat which I've gummed up but that had no effect. Not taken exhaust manifold or turbo off though.

At idle I'm reading approx 14kg/hr maf, 2ms injector pulse time, 6° btdc ignition angle (hunts about a little but generally there). All temp sensors agree when stone cold. I've done the Vida thermostat test and it's good. Will climb to 105 then fans bring it down to high 80s. I'm getting 0.8-0.9V on rear O². From front O² I get a random selection of either ECM-280A faulty signal or ECM-2810 faulty signal. Both O² sensors were new 2 years ago with the new cat. I've put 2 other new ones in and codes come back instantly. If I disconnect rear O² the car doesn't always throw a code for the front sensor and drops into closed loop when short term fuel trim climbs to +25%! Long term gets as far as +15% then stops. If I disconnect all sensors except maf it stills runs rich. I have a cloned ECU and it's exactly the same with that one too.

5 new coil packs put on and plugs are 8-9k old and gaps are good. All new stuff is Bosch by the way. This includes my replacement maf and O²s. Also replaced fuel pressure regulator, fuel pump and injectors.

I've had the engine bay loom out of its conduit and checked all wiring for damage, none that I can see. No shorts to anywhere or open circuits on anything to send from the ECU box connector.

Cylinder compression seems ok, warmed up dry/wet figures are 165/195, 160/180, 150/170, 160/180, 160/180. Is cylinder 3 too low in comparison or passable because it's at least 150?

Pulling 15 to 16 inHg from intake manifold brake booster port but it takes a while to get this high, starts around 13/14. Needle fluctuates ½"Hg at slow and steady rate.

Car has 239k on it. Is it time to say goodbye? Or does anyone have any other ideas that don't involve throwing more money at it. I'm happy to spend time testing and if I find a hard fault I'll pay to fix it but won't spend on a whim.

Thanks in advance.

Drew