I swear this car will be the death of me.

right. I *STILL* have a fault that doesn't command any DTCs or present a CEL.

specifically from a cold start it'll start on the button, and idle high (1100-1250rpm) for about 15-20mins of driving. at which point (when perceived fault appears) it'll idle low/hunt and hesitate low down - eg 3rd @1500rpm I can feel it hesitate/judder. stuff your foot into the carpet and she spins up. 

once fault condition achieved, I can knock off the ignition, give it 5-10s restart, it may splutter start, to may crank for 5-10s then fire. after such time drives like a dream. my local independent has concluded "its getting old" which, yes an '05 is getting there but its been very well looked after. to troubleshoot, its had iridium plugs. a replacement throttle body, replacement vacuum solenoid/purge valve, replacement pre-cat O2 sensor and most recently the intake manifold runner control circuit. all of which on the advice of DTCs or seeing other vehicles with similar symptoms. it must be said that replacing the TB and the solenoids means it no longer conks out randomly at idle when under fault condition. each component has helped in some way shape or form.

the really annoying thing is that it almost feels like its being commanded to run funny. (ie bad ECU?) maybe a bad coil? bad injector? coil pack? weak spark on one of the cylinders? coolant temp sensor? vacuum leaks? theres OBVIOUSLY something the car doesn't like on a cold start. I do have an MP4 to show the idling but MP4s aren't permitted attachments ☹

the ONLY thing that hasn't been done is to inspect the swirl flaps (as i know these are a common fault on the duratec engine) and I dont really want to have to fork out the c.3h labour (at £50/hr) to find out unless we're confident its that. I'm not convinced its this as after restarting it runs great.

 

I'm being quite stern on this one as its been a long standing fault that I really want to get to the bottom of, before I replace the old girl with a mk4 ST line X 182. On the flip side, its been a great car. I put some nice 18's on, Titanium spec, everything works, less a couple of small jobs (ie door check strap, brake light fault) AC ice cold, driving position is comfy. fuel is.. well as good as it can be for a 2.0 😂 elect mirrors/windows. heated screens both work, auto wipers/lights work etc.

 

 

Swirl flaps is a good shout

Perhaps it's coked up??

Yes, maybe swap out the coil packs? But are you getting a miss-fire warning?

Add an additional earth strap from the cylinder head to the body

What fuel are you using? If E10 switch back to E5

 

3 hours ago, DaveT70 said:

Swirl flaps is a good shout - It might be time :feelsbadman: as i know they are controlled via a servo/actuator which MAY be slowly (but surely) dying

Perhaps it's coked up?? - I had this thought but the ThrottleBody was replaced and has had 2/3 fuel treatments (miller oils "OneShot") if it is coked up i'll be very surprised 

Yes, maybe swap out the coil packs? But are you getting a miss-fire warning? - none. no misfire DTCs or injector DTCs - next time it goes in I'll ask the guys to resistance test the coils/injectors, maybe a bad ecu or parasitic draw?

Add an additional earth strap from the cylinder head to the body - might be worth checking out

What fuel are you using? In the past 7 or 8 years I've only used momentum99 or V-Power as I can feel a power difference between 95 and 99 octane fuel.

 

sat at 93k now i want the old girl to be a member of the 100k club. preferably not limping over the line. 100k for the duratec engine is almost broken in 😏😉