TD5's performance drops when warm

My 2001 90, responds excellently when cold, just the slightest prod on the throttle and she accelerates.

But when warm, she doesn't seem to be anywhere as near as responsive. You need to press the throttle alot more to get a similar acceleration, and it still doesn't feel as eager. It still will do 80+ on the mway, but at slower speeds it doesn't pick up as quickly.

Anyone got any ideas.

I've been pointed in the direction of the air flow sensor. How do I test for a fault?

Adsey

Hmm.
I have a 2002 90 Td5 and have noticed something similar when the ambient temperature is high. The car feels most responsive early in the morning when the air is cool and dense and with the engine warmed up to normal operating temperature.
Mine's a real slug on a hot day with a cold engine.

Mine seems to relate more to engine temp rather than ambient temp, but I'll have a think about that.

But I'd have to agree, on a cold morning their is a noticable difference in performance, but I think this is unrelated to the engine temp, but I'll try a warm engine on a cold day, and see what I think.

Cheers

When the outside air is COLD the intercooler works better.

This means colder air enters the manifold.

Colder air is denser air than warmer air, so a greater MASS of air enters the engine on cold days than on warmer days.

Therefore the engine goes better on cold days.
No doubt about it.

CharlesY

CharlesY said:

When the outside air is COLD the intercooler works better.

This means colder air enters the manifold.

Colder air is denser air than warmer air, so a greater MASS of air enters the engine on cold days than on warmer days.

Therefore the engine goes better on cold days.
No doubt about it.

CharlesY

Click to expand...

I think the OP was referring to the engine temperature not the air temp...at least thats the way I read it...

So although chipping/remapping/interrupter boxing the Td5 gives excellent bang per buck performance upgrades, you would be better off upgrading the intercooler first?

Found these two posts on another thread, looks like the same problem to me.




Re: TD5 power/revs fade
My 2004 90 TD5 is a pain.I have had the new turbo fitted and it goes very well pulling from 1200 revs like a train. When cold i hardly have to touch te accelerator and it flies. However, after a short journey and it gets up to temperature the performance seems to tail off again and i have to press the accelrator further to get the same performnce, and it would seem some turbo lag too.I am thinking that boost pressure may be reducing as the temp rises causing the drop in performance my question is, can the electronics/ECU reduce the amount of boost availale and if so can i make it stop!

Re: TD5 power/revs fade
have now disconnected the EGR valve. Much better it would appear...


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might need to try doing that!