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Couple of Ford Fiesta 1.25 LX 1999 48k "V" reg problems!

Just found this group, so Helloooo!

First problem, the recirc doesn't seem to want to work, the light comes on, but it doesn't divert the air, is this a common problem?

Second problem is, the engine seems to stay at high revs when it should be idling, but only if the car is moving. If the car is stationary, it will rev up as expected when pressing the accelerator, then the revs fall back to normal idle, however, if I am moving (even slowly (5mph) they will stay high (2000rpm ish) then fall once the car has stopped. I tried this on a hill, stopped in traffic, then when the traffic moved, just let the car roll, the revs too them self up, despite the fact I didn't touch the accelerator, and was in neutral. - is this a common fault too!?

Thanks for any advise!

Sparks...

Reply to
Sparks
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This is not a fault of any kind, its meant to do it, infact virtually all fuel injected cars do so. You're not meant to coast in neutral or clutch down.

Tim..

Reply to
Tim..

No way this is normal!

If the car is idling, then I roll the car at even

Reply to
Sparks

It's Advice.

Reply to
gazzafield

Idle hang is normal, and its programmed into the ECU to cut emissions and to better prevent engine stall when coming to a halt. However I would way that

2500rpm is too high- it should be around 1500rpm.

You can often (but not always) adjust the TPS to give a slightly lower voltage throttle shut. If its around 0.8v, back it off to around 0.6v.

The engine does return to an 800-850rpm idle when stationary doesnt it?

Tim..

Reply to
Tim..

I don't think the problem isn't related to the throttle, as if the car is stationary, and the revs have dropped to the normal idle level, if the car is simply rolled forward (out of gear) the revs pick up again, I could of course be reading this wrong!

Yes, when stationary, it's fine.

Reply to
Sparks

no, it's advice, no reason to capitalise it, is there?

...and what a great help you are, a real asset to the group I see...

Reply to
Sparks

We seems to be going around in circles. I recommend you pick up a good reference manual on modern fuel injection systems and have a good read. It may illustrate to you how the ECU interprets signals from the Throttle position sensor (TPS), the vehicle speed sensor (VSS), the engine speed sensor (CAS) and from reading from its stored software manipulates the idle control valve (ISCV) according to what the car is actually doing.

With EFI, the car is never at 'idle' or 'not at idle' - unlike it was with a carburettor; it can be at about 9 states inbetween according to what its doing, and what idle strategy the ECU is implementing. No two engines are ever the same, and some exhibit more pronoucned behaviour than others.

However your 2500rpm idle flare is excessive and can be reduced.

An increase in revs from base idle whilst the vehicle is moving IS normal though.

Thats fine then.

Tim..

Reply to
Tim..

sounds like a dodgy TPS - I had the problem on a 93 fiesta. It used to surge like that, including when coming to a stop, upon which it would hunt for a few seconds, then sort itself out.

I found that when it started playing up, I could generally resolve it by letting the engine warm up to the point at which the radiator fan cut in, then turn it off. Next startup it would be fine for a few days or even weeks.

Eventually replaced the TPS, never had the problem again.

Rob

Reply to
Rob Ellis

THANKS!!! :-)))

Reply to
gazzafield

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