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No i don't mean the EA82T being the issue It has isues...

When i start the car cold it has trouble idling up it will cough & splutter until i tap the loud pedal. let it warm up for a minute of so & then i drive off it comes on to boost quickly but it hesitates BADLY, like there is no boost then as i am about to change gear it takes off like a rocket! it will do this in every gear until i hit forth & coast along. I put my foot down & again the car hesitates BADLY. it will do this until it gets up to operating temp. BUT it still hesitates just not as noticeable as when its cold.

If i turn the car off & let it sit for 2 or 3 Min's then start it again it will act like it was cold until the thermo fans kick in.

Whats wrong with it (besides it being an EA82T)..

I have given it new plugs, dizzy cap / rotor/ ignition leads, fuel filter, injectors, fuel pump, vacuum lines.

I'm thinking it might be either the MAF or the fuel pressure reg.
Though i have tried another MAF & it still did the same thing....

Any answers world be much appreciated.

You havent got a bad earth strap to the engine?

It might also be worth while seeing if the computer is reporting any fault codes by putting it in diagnostic mode. If the EA82T is the flap type airflow meter setup (as opposed to the hot wire airflow meter) the computer is fairly basic and will only report problems as it see's them so it's not the best for capturing problems but you might get lucky. I don't think you mentioned checking the engine temperature sensor either, might also be another one to look at. Make sure you check the temp sensor that the computer uses (towards the rear of the motor adjacent turbo) not the one the dash guage uses (underneath the thermostat). It's not uncommon for the EFI temp sensor to corrode the contacts out on the connector.

Dave it has got a 3 point earthing system on it so I'm hoping the earthing is good enough.

As for fault codes there are none except for the usual starter switch one.
It is a flap style. i have cleaned the contacts on the coolant temp sensor plug (the one near the snout of the turbo) & replaced the temp sensor with a new one.

I'm thinking its fuel not electronics........ But i cant be sure...

Or its time for a dyno...

Sounds like its not getting enough fuel. As you think it could be fuel pressure reg or you have a crank vent valve or line ajar.

or too much fuel
I 2nd checking the engine temp sensor.........

Yeah, probably would help if we knew if it was getting too much fuel or not enough? Any black smoke from the exhaust while it's coughing and spluttering?

Also, on reading your description again it sounds like the spluttering is when the computer is working in Open loop mode. In closed loop mode such as when you're cruising in 4th the computer will be using the 02 sensor to get the mixture right and compensate to some extent for any vacuum leaks or fuel pressure problems. As soon as you come on boost or go over 3500rpm the computer goes open loop and normally enrichens the fuel mix and because it is running on pre-programmed mappings does not compensate for any problems in this mode.

Check to see if the problems happen while the green turbo boost light on the dash is on. It should take a couple of seconds for the computer to switch to open loop mode after the green light comes on, and should switch back to closed loop mode almost immediately the green light goes off.

There is no fuel / black smoke at any point in the rev range except when the BOV goes off .

Interesting on what you are saying Gremlins about the Open / Close loops.
But when the boost light comes on it still stuffs around for 4 maybe 5 seconds the it surges.

I'm still bugged what it is, Might go & buy a Rising rate fuel pressure regulator.....

Interesting, well it's obviously not getting too much fuel. Also when you say that after 4 to 5 seconds after the green light comes on it surges, does that mean that it sorts itself out and accelerates like it should, or surges as in starts bucking around?

It starts bucking around, its not violent but is still very noticeable.
It will eventually sort its self out but by then I'm ready to grab the next gear.......

Unfortunatley still could be a number of things. It's probably going to be a bit more trial and error. It would be good to eliminate the fuel pressure regulator as a problem. The other thing to check is if all fuel injectors are actually firing. I see you changed the injectors but may be worth doing the screw-driver on the injector trick to make sure you can hear all of them ticking properly.

All the injectors are working fine, i had them checked in the car by an EFI specialist.

Might go & buy a fuel pressure reg...

you said you replaced your fuel pump

what pump did you replace it with? can I ask what it cost?

Air Leak?

Fuel pump is a BIG Bosch one (not sure of model but its 205Lph) I paid $0, its on 'trial'.

Air leak?? Don't think so as it idles @ 20InHg , but i will have a look.

hello everyone,
i also have a ea82t with some idle problems, everybody is talking about that temperture sensor that the ECU uses, tot check that one.

but where can i find it?....

thnx!

The temp sensor is just behind the throttle body, rather hard to get at plug. It is mounted in the intake manifold crossover coolant path. Should get code for faulty one (21). At 20degC it should be 2-3k ohm, 50degC is 700-1000K ohm. No test point in harness plugs, but does go to one of 2 main engine plugs (see diagram in manual Downloads)

gremlins said

It might also be worth while seeing if the computer is reporting any fault codes by putting it in diagnostic mode.

How does that work, putting the computer in diagnostic mode???

Gr Marc

Puma, fault codes should flash LED if conditions are not true.
To go further to define code, the test plugs found in the wiring near to ECU should be GREEN male and female connector plugs. They set the ECU over a full range of testing, like igntion on, the at idle then after full revs, then after a short drive would test all conditions and then check codes.
(Note the BLACK connectors next to them are to reset the ECU)

does anyone know the resistor values for the sensors involved and if so do these fit within that available on a restistor wheel available from Jaycar $20 or the DickMaker Electronoics $30. rig this up between the sensor wire to computet and the vehicle eart and dial in various values manually to see if you can make a change ?