Mark - bet you it's the factory loom. If you need more info gimme a buzz. Cheers, Nicko

replace the coolant temp sensor and see if that makes any difference I have has the same issue with my n/a. Running rich as and overfueling itself causing to run like poo! On to my 3rd o2 sensor now, which seems to fix the problem. Do you have an exhuast leak at all around the exhuast manifold area? Might wanna get that exhuast cleaned out of any carbon build up...

Quote: Originally Posted by InsaneVL Fuel pump has been changed. sorry bud didnt see that Could be water in the tank.. a little bit of metho would help absorb it.. Could try a bottle of tank cleaner.. from memory Wyn's is a very good brand. Whack it in your tank with about 60 litres.. and let it do its magic..

Ok. Car was at the Auto Electricians for 2 days and confused the hell out of him. He tested all the sensors and all came back perfect. All the connectors are good to all the sensors. Fuel Pressure was tested - all ok, not spiking, and not leaking. Next things on the list I suppose is to test the ECU and the wiring loom itself. Anyone got a Turbo ECU I can borrow to test out? Further to that - anyone got a Turbo Engine Loom I can borrow??? Nick?

dude i have similar prob and have replaced everything possible. mine idles like crap and hesitates when accelerate, and gets good when around 3000rpm. but blows black smoke when boosting above 7spi i put in na ecu and all is perfect. bought new turbo ecu and plugge it in but still runs like crap. ive given up

My old calais did exactly this, was only an NA, but it spent a week and a half at the Auto Electricians and cost me heaps of $$$ to get it sorted out. Yes it was a wiring problem.... They told me the wiring that goes to the CAS was screwed, were a bit vague because they probably wanted me to come back and spend more $$$ for them to fix it again instead of doing it myself. Anyways I think the wiring was pinching or pulling where it joins the rest of the loom and that causes contact to break. After I had it fixed by the shop, it used to do it every now and again, sometimes a big backfire and puff of smoke and it would run like ****. Pop the bonnet wiggle the CAS plug and gently pull on the CAS wiring and it would fire up again and run normal. Hope this makes sence and is of some help!

Yeah... i'm suspecting a wiring problem along the line somewhere. Will need to change the loom and see if that changes it... Does anyone have a spare Turbo Engine Loom????

I think it definately sounds Oxy sensor related. Depending on conditions i.e. TPS input, Engine Temp, Engine load i beleive it can stay in closed loop till up around 4000rpm. I would check wiring from the OXY sensor plug back to the ECU. From my experiences an AFM problem will be there from idle to max rpm. You say yours comes good at around 300rpm, could just be going open loop and not using the oxy sensor any more for mixture control. There is a join in the wiring harness you could check if you think its definately AFM related. Its in a section of the harness underneath your inlet manifold, around No 4 cyl area. Its an 8 way crimped/soldered join. One wire comes from your reverse polarity relay, one from the AFM, and the other 6 are 1 for each injector. Water gets into your harness and corrodes the join and individual wires break away. When i have seen this happen though it has always resulted in stalling the engine. That may be a point to check but i dont think it would cause your problem. Start the car up and give the harness a shake in that area, see if it comes good. Also test for power to your AFM plug while wiggling that harness in that area. If the join is really buggered you wont have power there at all..

ok... changed computers with a known good unit - still same problem changed wiring harness with a known good harness - still same problem changed spark plugs (twice) including a new set set to a smaller gap (26 thou gap) - still same problem changed leads to expensive 9mm Qld Ignition Leads - still same problem changed Ignition Coil (again) to known good coil - still same problem I'm ****ed with what this problem is. Any other ideas guys ????

o2 sensor....

Got me screwed as well then Marky, i thought for sure that loom and my leads would have sorted it Some original photos have not been recovered yet.

Anyone got a Compression Tester I can borrow ????

I had the same problem for the last 12 months, Found out i had 2 problems, 1st was the CAS, went through 3 before i bought a new one, Car kept going, but would randomly go **** and stall on me. 2nd problem was a bad injector, I would be driving along fine, then it would just start pouring in the fuel, -black smoke everywhere. I had to unplug it to stop the smoke. It wsnt the plug or leads cause i changed them and i had good spark. IF you take out the plug straight after it runnin crap like that, it will be wet from fuel. mine done it on a new injector too. It could also be yr leads to injectors shorting out , but probly not if you changed it.

have you tested injectors yet? my spare set are in good condition if you want to try them.

Yeah mate - might try another set aswell - got a few people wondering if its a leaking injector. Doesn't sound right to me since all spark plugs are going black. But anything is worth a try at the moment. Is it cool to pop over tomorrow after work (about same time as last time) ?

I won't be home from work till prob 6ish so anytime after that is fine.

Your going to need to check the fuel pressure for sure if you haven't and its rich. The return line venturi or hose could be blocked causing high fuel pressure. Should be 32psi with vac source connected to fuel reg and 40psi with it disconnected. If you don't do this as your next check, you could end up going in many circles.

Fuel pressure has been tested and is perfect.

ok, well thats a good thing to rule out, now your mainky focused on the electrical side of things. have you check the coolant temp sensor, isn't reading cold, and causing a rich fuel mixture?

Changed Coolant Temp Sensor - Auto Sparky had it on the osciloscope aswell. Changed the engine wiring harness aswell.