Thread: TD5 - recent Turbo Lag!

Originally Posted by LandyAndy

Hi Steve
Mine is slow till it builds up a head of steam,600 to 700 max from a tank,was 800 to 1000 once upon a time.
The wastegate is opening closing(not stuck).
With a trailer on in hot weather its real sad,used to pull my big tandam trailer with 2 tonnes firewood easily,would be a real struggle now.
My 235/85 tyres wont help the situation,but dont belive they are the only cause.

Andrew

have you chcked to make sure you are getting full throttle.......?

I would love to Tony
But the only way is with a new fly by wire isnt it????If there is another way,let me know ready to try anything.From lots and lots of posts the AFM always comes up.
Im ready to buy a newie just to rule the thing out.At least I will have a spare if its something else.
Andrew

Originally Posted by LandyAndy

Hi Steve
Mine is slow till it builds up a head of steam,600 to 700 max from a tank,was 800 to 1000 once upon a time.
The wastegate is opening closing(not stuck).
With a trailer on in hot weather its real sad,used to pull my big tandam trailer with 2 tonnes firewood easily,would be a real struggle now.
My 235/85 tyres wont help the situation,but dont belive they are the only cause.

Andrew

Something to be aware of...

If the ecu has initiated fuel cut-out due to excessive boost, then even after the offending part is fixed/replaced, the ecu will not allow more than base boost (via the wastegate modulator) until the excessive boost fault code is cleared. ie only 1 bar boost compared with about 1.3bar.

Thanks Greame
Once I get a new AFM I guess a computer clear is a good idea.
Last time it was wiped they had never seen so many faults.
I had a head gasket and oil in the harness in 1 hit.Most of the faults were put down to the oil.
Andrew

Originally Posted by LandyAndy

I would love to Tony
But the only way is with a new fly by wire isnt it????If there is another way,let me know ready to try anything.From lots and lots of posts the AFM always comes up.
Im ready to buy a newie just to rule the thing out.At least I will have a spare if its something else.
Andrew

oops......

i think im confusing threads.......
i was thinking tdi for some reason.......and yes......its really been a monday for me today.....can you tell...?

Originally Posted by LandyAndy

Last time it was wiped they had never seen so many faults.
Andrew

yep agree with a lot coming from the oil in the harness thing but a dodgy earth in conjunction with that can cause pure bedlam for the ecu log.

Originally Posted by LandyAndy

Hi Trev
I have a new spare one of these.
I just checked it,with no power connected you can blow thro the lower inlet port and it blows thru to the wastegate port.
Im thinking the 12v power supplied by the ECU closes the valve stopping you being able to supply air pressure(BOOST) to the wastegate,the ECU should open the valve to supply boost to the wastgate to open it at the correct boost level.
With your blow test did you have it plugged in and ignition on????
Thanks for the post,I will fit the newie and let you blokes know how it goes.
Andrew

Sorry for not getting back sooner.Yes voltage needs to be applied.
Unless you have super lungs the valve should not open from the lower turbo pipe input until an over-boost situation occurs which will be over 1 Bar at least.

trev.

Originally Posted by trev

Sorry for not getting back sooner.Yes voltage needs to be applied.
Unless you have super lungs the valve should not open from the lower turbo pipe input until an over-boost situation occurs which will be over 1 Bar at least.

trev.

The modulator, when operating correctly, allows the high pressure line from the turbo outlet to pass through to the wastegate actuator so that the wastegate will open at around 1 bar unless the ecm supplies a (pwm) signal to the modulator to partially dilute the high pressure with low pressure from the turbo inlet so that the high pressure can go higher. The ecu will allow under certain conditions a maximum pressure that equates to about 1.3 bar at the turbo outlet with a std intercooler (mine dropped by 2psi at the turbo with an i/c with better flow).