The TS has all the power and response when cold but once it reaches OP temp it seems to go into fuel starvation mode? What is it. If the fuel filter is blocked the worst part should be startet up. Coil ? Resently had injectors cleaned? But just as it want's to go to 80 -90 kms brrruum missmiss ok. Can't be plugs there good.. Sooo I scratch my head and wonder WTF! Is there a pre fuel filter at the tank and if so that might explain the reason it is good at cold because the suction on the tank filter may take a while to take effect and then bruuum missss? OK am I a DH or is there something I am missing?

Maybe O2 sensors?
Know they don't do a lot when the car is in cold start/fuel enrichment mode...

I would say O2 sensors too. They only kick in when they have warmed up to operating temperature. When you first start your car, it will run a pre-programmed slightly rich mode. The O2 sensors basically allow for better efficiency. If the O2 sensor is crook in some way, it will throw the air/fuel mixture out to the extent where power and fuel efficiency are compromised. Last year I had an issue with the O2 sensor on my TF, where the O2 sensor developed a fault that actually affected the air/fuel mixture so bad it stalled the car. This at least showed that the O2 sensor is an important component. That said, the O2 sensor is probably one of the more neglected components and usually not replaced as required.

Fuel pressure regulator on the fuel rail may also be suspect.Cheers Vee

Also test the resistance of the spark plug leads.

The TS has all the power and response when cold but once it reaches OP temp it seems to go into fuel starvation mode? What is it. If the fuel filter is blocked the worst part should be startet up. Coil ? Resently had injectors cleaned? But just as it want's to go to 80 -90 kms brrruum missmiss ok. Can't be plugs there good.. Sooo I scratch my head and wonder WTF! Is there a pre fuel filter at the tank and if so that might explain the reason it is good at cold because the suction on the tank filter may take a while to take effect and then bruuum missss? OK am I a DH or is there something I am missing?

I'd say start basic before jumping straight to stuff like o2 sensors. (FIRST off, i'm assuming you have a 4 cylinder, if not check the spec values at the bottom for V6)

AIR, SPARK, FUEL, TIMING. You need all four of these things, for an IC engine to function well. If any are compromised, it won't run well.

I find it easiest to go in the order of simplest to check, to most complicated last.

1. AIR - Everything to do with intake,

A. Air filter - is it clean/unblocked? (remove and test without)
B. Vacuum leaks - spray ether around intake piping if idle changes, you've got a leak
C. Gunged up throttle body? - Clean it.
D. Bad throttle position sensor - easy to reset with multimetre, download manual and follow instructions
C. Air flow metre - is it still original? Is it known good? Wiggle connector with engine running, if it stumbles you might have oxidised connections in which case replacing the plug/cleaning the pins on the MAF will help
D. Idle air control valve? Unlikely to cause said problem but since you're checking the intake, you may as well check that it works, simple to do, undo the two screw/bolts, leave it connected and start engine, you should observe it actually working. If it does nothing..... it's cactus.

2. SPARK -
A. Do you actually have 13.6-14.2v @ the battery? - Are the terminals OK? Especially your earth? If not, grab a terminal brush ($5 from SCA, does wonders have good connections @ the battery)

B .Start from the power transistor with a multimeter (Make sure car is at OP temp) - check resistance it ought to be 16Ohm +/- 3 Ohm

C. Check primary/secondary coil resistance while HOT, if primary resistance is more than 1Ohm it's cactus. Be sure the coil is actually quite warm (The warmest it'd get on a hot day), secondary resistance ought to be 10-13kOhm, if more than that, cactus again.

D. Wiggle the connector on your distributor while the engine is running - these are well known for oxidising resulting in bad connections, if it misfires/coughs, you'll need to get a new plug from an auto electrics supply place, and replace it, smear with a good dose of dielectric grease to prevent.

E. If your leads aren't at least newer than 12 months, grab some bosch super sport leads, OR if they seem OK, check the length, less than 63.5cm should be less than 30kOhms, greater than 63.5cm, less than 50kOhm

F. How do you know the plugs are good? How old are they? What color are they? Grey? White? Black? Oily black? Is the gap 0.7-0.8mm?

FUEL -

A. When did you last change your fuel filter? Just because it can idle doesn't mean the filters not blocked up with gunk.

B. Is the fuel pump & regulator good? You'll need to take your car into an EFI specialist place for this, unless you have a fuel injection testing bench etc

TIMING -

A. While yes the ECU does it's thing to advance the timing, and you still adjust it by just unbolting the dizzy mounting nut and moving like the old days, you do still need to set base ignition timing to 5 degrees BTDC (plus/minus half a degree)

B. Valve timing, i'd be a little doubtful this would cause your issue, leave this as a last on the list/it's getting very complicated.

ROUND UP -

OK if you haven't found anything in your diagnosis travels of the above, it may be a much bigger issue, in which case a;

Vacuum gauge and
Compression tester

Will tell you more.

Your engine won't run well and it will miss if a single cylinder has really poor compression.
If you have two cylinders side by side with low compression you might have a semi blown head gasket.
You might have leaking valves, you'll need to do both a dry and wet compression test, if compression doesn't come up on the wet test, leaking via valves. If you are leaking compression out the valve, double check that you don't have an exhaust leak, otherwise you'll have badly burnt exhaust valves, which will require reconditioning of the cylinder head.

The list kinda goes on, and on, and on. You just need to be very methodical, test each individual system and tick off that it is known as working correctly.

HOPE THIS HELPS :eek2:

NOTE;

V6 plug gap; 1.0mm pre-gapped
COIL; Same as 4 Cyl

Thanks for all the help. It's a 3.0L auto and the car was given new oil, air filters etc, coolant change and I did have a slight head gaskget leak but is was just a dribble coming from the drivers side front bank and a can of rislone fixed that. There was no coolant loss into the oil or out the exhaust so that rules out head. O2 sensor I did not think of .. and I was going to replace the plugs anyway. The lead are in good shape as is just about evey thing in the engine bay. The thing that really stumps me is that, some days it does not do it much and others it does. And it is not like " high humidity or low " makes much diff . Is there a pre fuel filter at the tank end that could be the culprit?

I have checked most of what you have sugested, so I think the prob might be the O2 sensor. I had a look on line and $110 was about the cheapest but of course there is not a price for gen part. Looks like a shit place to try to get to replace but I would rather a mech do it . Any idea of cost MR Mitsi..... thanks