Discussion
Hi guys, I've just finished reading through all 75 pages on here and can't find the info I want.
My fiesta (bought for my girlfriend to learn to drive in) has a few issues. Help with any of them will be appreciated. It's a 1997 1.25 Zetec-S.
1. Heater only works at high RPM. Most heater questions on here centre around the heater valve, by which I think they mean this bit:
Only problem is on mine the pipes are hot on both sides of the valve all the time. Any ideas?
2. Sticking throttle.
The throttle mech, cable and pedal all move freely and the throttle spring is very strong. If I rev the car to any speed less than 3,000rpm it falls back to idle fine. If I rev it to 4,000 or above it takes 10 to 15 seconds to reach idle again unless I drag it down with the clutch.
Could that be the throttle position sensor? The car had a new one a few years back according to the service history.
On that subject, does anyone know what the rest of this label says? I can't see all of it even with the camera phone.
I saw the idle control valve mentioned in some posts on here and guessed that might be resonsible - I think they mean this.
I've removed it and cleaned it with electrical solvent, but frankly it looked absolutely fine and I removed virtually no dirt.
3. Power/economy.
The car pulls cleanly from just above idle to 3,00ish RPM then runs into a wall. It takes several seconds to reach 4,000ish rpm then proceeds as if nothing happened. It returned 22mpg on the motorway trip back home which is actually marginally worse than my MR2 Turbo does on a similar run.
Any help much appreciated!
Alan
My fiesta (bought for my girlfriend to learn to drive in) has a few issues. Help with any of them will be appreciated. It's a 1997 1.25 Zetec-S.
1. Heater only works at high RPM. Most heater questions on here centre around the heater valve, by which I think they mean this bit:
Only problem is on mine the pipes are hot on both sides of the valve all the time. Any ideas?
2. Sticking throttle.
The throttle mech, cable and pedal all move freely and the throttle spring is very strong. If I rev the car to any speed less than 3,000rpm it falls back to idle fine. If I rev it to 4,000 or above it takes 10 to 15 seconds to reach idle again unless I drag it down with the clutch.
Could that be the throttle position sensor? The car had a new one a few years back according to the service history.
On that subject, does anyone know what the rest of this label says? I can't see all of it even with the camera phone.
I saw the idle control valve mentioned in some posts on here and guessed that might be resonsible - I think they mean this.
I've removed it and cleaned it with electrical solvent, but frankly it looked absolutely fine and I removed virtually no dirt.
3. Power/economy.
The car pulls cleanly from just above idle to 3,00ish RPM then runs into a wall. It takes several seconds to reach 4,000ish rpm then proceeds as if nothing happened. It returned 22mpg on the motorway trip back home which is actually marginally worse than my MR2 Turbo does on a similar run.
Any help much appreciated!
Alan
Regarding the Heater Control Valve (HCV) issue (your no.1 i believe). You have put an arrow to the correct part.
This is common on these Fiesta's, check the part number begins with 98... if it does, go get an older one that begins 95 (they're on Mk4 Fiesta '95-'01 and the Ka of the same age).
It's 4 jubilee clips to get off and replace, the part will cost about £3 from a scrappy.
The 'faulty' HCV's apparently don't let enough hot water through.
The HCV problem had my old mechanic stumped, they can cause varying problems (car overheating / no hot air / no cold air are the most common). My first one on the ZS they thought could be the head gasket, then they thought it was the thermostat.
I left the car overnight with them so they could scratch themselves about it, i then did some research on www.zsoc.com, which turned out that this is a very common problem.
If you change that first (it may just be knackered - it's a stty cheap Bosch part anyway) it's only going to be a few quid, which is better than 'trying' a new thermostat which wouldn't solve the problem anyway if it is the HCV. You've got nothing to lose trying this first.
Regarding your other problems, sorry I cant offer any advice.
This is common on these Fiesta's, check the part number begins with 98... if it does, go get an older one that begins 95 (they're on Mk4 Fiesta '95-'01 and the Ka of the same age).
It's 4 jubilee clips to get off and replace, the part will cost about £3 from a scrappy.
The 'faulty' HCV's apparently don't let enough hot water through.
The HCV problem had my old mechanic stumped, they can cause varying problems (car overheating / no hot air / no cold air are the most common). My first one on the ZS they thought could be the head gasket, then they thought it was the thermostat.
I left the car overnight with them so they could scratch themselves about it, i then did some research on www.zsoc.com, which turned out that this is a very common problem.
If you change that first (it may just be knackered - it's a stty cheap Bosch part anyway) it's only going to be a few quid, which is better than 'trying' a new thermostat which wouldn't solve the problem anyway if it is the HCV. You've got nothing to lose trying this first.
Regarding your other problems, sorry I cant offer any advice.
In regards to your car reaching 4,000 and hitting a wall, mine has the same problem. It is also using a lot of fuel. I took it to a garage and he said it was the MAF Sensor after running a diagnostic machine on it. I shall replace this in due course and let you know what happens.
Cheers,
Mark
Cheers,
Mark
_Al_ said:
I was wondering about that. The car had a throttle position sensor recently and if it was the Air flow metre the thing would surely cut out at high revs rather than get past 4,000 and continue as normal?
Dont know mate to be honest. All mine used to do was get to 3500 - 4000, start holding back and you really had to put your foot down to get over the 'hump.' Lastnight i changed the MAF and it now accelerates cleanly. Will have to wait and see what happens with the fuel consumption, but it has definitely sorted the underpowering situation out. The part cost around £65 from Unipart.Gassing Station | Ford | Top of Page | What's New | My Stuff