Ford Ka - Performance/economy and coolant level. - Heyes

For years my son has claimed the performance and fuel economy of his 05 Ka significantly worsens when the level in the coolant reservoir drops below the minimum (even though it's not empty).

Although not pretending to be smart enough to understand this, I can't see any reason why this should be... yes, I can see how performance and fuel economy can vary for a variety of reasons (including faulty sensors/electronics), but not related to the level in the coolant reservoir.

Am I just stupid?
Is he mistaken?
Maybe it's a ploy by Ford/oil companies/whomever.
Are there dark forces of the supernatural at play here?

Suggestions appreciated.
Please and thanks.

Ford Ka - Performance/economy and coolant level. - bolt

it can happen where the level of coolant is low enough for high engine revs to pull all coolant away from header tank, so that there is none around the temp sensor, this temperarily tells the temp sensor, engine is cold and increases the fuel consumption as sender unit is telling ECU engine is cold

Ford Ka - Performance/economy and coolant level. - elekie&a/c doctor

Less water=less weight=more performance.? The coolant level would have to be very low to affect temp sensor reading.At that point the heater would probably not be working.

Ford Ka - Performance/economy and coolant level. - bolt

Less water=less weight=more performance.? The coolant level would have to be very low to affect temp sensor reading.At that point the heater would probably not be working.

Used to happen on the 1.1 ohv fiesta, so not impossible

Ford Ka - Performance/economy and coolant level. - Heyes

it can happen where the level of coolant is low enough for high engine revs to pull all coolant away from header tank, so that there is none around the temp sensor, this temperarily tells the temp sensor, engine is cold and increases the fuel consumption as sender unit is telling ECU engine is cold.

Thanks.

Hhhmmm.... interesting.

I get the bit about the sender sending a 'cold engine message', but hadn't heard about 'high engine revs pulling coolant from rerservoir'. How low would the level have to be?

Ford Ka - Performance/economy and coolant level. - gordonbennet

I'd be more concerned about where the coolant is going, if its ending up in the inlet or combustion chamber(s) then wetting the plugs at certain times, then that could explain poor performance, but whatever is causing the loss of coolant isn't likely to fix itself.

Ford Ka - Performance/economy and coolant level. - skidpan

Wifes uncle had a Fiesta fitted with the same OHV engine as the KA. Ran sweet enough for years then it started drinking fuel like it was free and stank like a 60's Anglia at the back end. All gauges read normal, it started fine and ran well until it had done about 10 miles then it rapidly went down hill. Local garage checked the obvious with the exhaust probe and as expected the readings were off the scale for CO's and HC's, no way it should have even have been on the road. So their young mechanic whipped the connector off the ECU temp sensor and the car ran perfectly. His explanation was the ECU was getting a reading that indicated that the engine was overheating and to prevent piston damage the ECU overfueled to cool them down. From cold the readings were probably in range. By disconnecting the sensor it reverted to a default figure that was within range and all was OK. He later fitted a new sensor simply because in winter you need some enrichment on a cold morning.

Coolant level should make no difference unless its either empty or blowing out of the expansion.

Ford Ka - Performance/economy and coolant level. - elekie&a/c doctor

I think you will find that a Ka of this age will be fitted with one of these;www.youtube.com/watch?v=ohGepY1sWqo

Ford Ka - Performance/economy and coolant level. - jc2

An '05 Ka will be Rocam(OHC not OHV).I've owned Ka's with both engines and a Fiesta 1.1 OHV.None of them were affected by level of coolant-in fact,other than for leaks, the only change in level should be for expansion and none of my vehicles needed any topping up of coolant.The Fiesta had,of course,a swing spout for cold weather use to overcome carb and throttle body freezing

Ford Ka - Performance/economy and coolant level. - skidpan

Wifes uncles Fiesta was a 2000 1300 (according to Wiki an Endura E) which was also used in earlier KA's. So not the same engine as the OP's later KA.

Thought all KA's used the same OHV engine until the joint Fiat/Ford KA but obviously not.

Must be said that having driven several mid 2000's KA's as courtesy cars it was very good of Ford to make the OHC engine sound like a rattly good old x-flow.

Ford Ka - Performance/economy and coolant level. - jc2

The Ka changed about March 2003 from OHV to OHC;both were 1300 cc. but the OHC produced about 10 hp. more.Don't understand the "rattly" comment.The ROCAM was chain drive cam,roller cam followers and hydraulic tappets.The StreetKa and SportKa were fitted with a 1600 cc. Rocam. The Fiat engine only came in with the Mk 2 Ka. which was Fiat built.

Ford Ka - Performance/economy and coolant level. - Heyes

Coolant level should make no difference unless its either empty or blowing out of the expansion.

Thanks.

That's my view understanding too - but I'm no expert.

Hell, many of the cars I've driven didn't even have a reservoir. (And I can remember an emergency top-up of peeing into a Cortina radiator after struggling up Telegraph Hill in Devon many years ago. They don't make 'em like they used to... which is probably somehting for which to be grateful.)

Ford Ka - Performance/economy and coolant level. - Heyes

I'd be more concerned about where the coolant is going, if its ending up in the inlet or combustion chamber(s) then wetting the plugs at certain times, then that could explain poor performance, but whatever is causing the loss of coolant isn't likely to fix itself.

Thanks.

It seems to be a relatively piddling amount - perhaps a cup a week... certainly much less than I've been used to losing from a variety of s***heaps since my first Anglia more than 40 years ago. ;-)

It's been happening so long, and without other signs of a head gasket or other failure that my view has been 'leaky hose'. Having sent it for check and repair a week or two ago, the water pump was replaced, since which he yesterday added probably just a cup and is once again concerned. (I told him it's probably just settling and losing air - but I don't pretend to be an expert and may simply be talking nonsense.)

Ford Ka - Performance/economy and coolant level. - skidpan

Don't understand the "rattly" comment.

Just looked at Wiki and it appears the OHV Endura was used in the KA until 2002. The courtesy cars we had covered the years 2003, 4 and 5 so its possible that they were earlier KA's fitted with the OHV engine and not the later OHC unit.

But who knows, its a long time ago.

 

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