Go Back   Team-BHP > Under the Hood > Technical Stuff


Reply
 
Thread Tools Search this Thread
Old 26th April 2013, 20:13   #16
BHPian
 
karthik123's Avatar
 
Join Date: Aug 2010
Location: Hyderabad
Posts: 74
Thanked: 35 Times
Default Re: Ford Fiesta: Sudden Drop in Fuel Economy

hello,

How is the cooling during night?
I had a similar problem in my verna with AC cutting off during the day ( when the weather gets really hot!) and in traffic, works in the evenings
I got the evaporator coil changed the problem persisted, then the AC guy had a lucky hunch and he checked the gas pressure, he found it to be too high.

The problem was the gas was filled at night so more mass of it entered the system, when it gets really hot it expands forcing the ECU to switch off the compressor, so he bled some gas from the pipes and its working fine

I had a similar experience of getting hot air from vents, so please check this aspect too because you mentioned the condenser was changed recently, those guys must've filled extra gas while topping up !

Last edited by karthik123 : 26th April 2013 at 20:16.
karthik123 is offline   (5) Thanks Reply With Quote
Old 27th April 2013, 08:21   #17
Senior - BHPian
 
anachronix's Avatar
 
Join Date: Mar 2006
Location: Madras
Posts: 3,250
Thanked: 1,241 Times
Default Re: Ford Fiesta: Sudden Drop in Fuel Economy

I connected the Torque Pro yesterday when I drove back home from work. The traffic was quite fast, except for a B2B traffic for 10mins or so.

Observations:
1. AC was working normally, it never cut off
2. The engine temperature hit the highest of 90C
3. The Avg. KPL numbers on the torque pro indicated an increase from average of 8.1KMPL to 9.8KMPL by the time I reached home
4. I am going to observe the same data when I drive to work in hot conditions of the day

I am leaving the car for the detailed checkup only on Monday, weekend crowd for regular service and my engineer wants to work on the car when he is relatively free.

Quote:
Originally Posted by vikramd
Things that you need to ask them check are as follows
I never observed this, but I vaguely remember the AC cutting off when I was stuck in heavy traffic for close to 20mins sometime back.

Quote:
Originally Posted by karthik123 View Post
How is the cooling during night?
anachronix is online now   Reply With Quote
Old 6th May 2013, 09:06   #18
Senior - BHPian
 
vikram_d's Avatar
 
Join Date: Jul 2006
Location: Bangalore
Posts: 2,380
Thanked: 936 Times
Default Re: Ford Fiesta: Sudden Drop in Fuel Economy

So buddy, any updates on the problem and it's solution if any?
vikram_d is offline   Reply With Quote
Old 6th May 2013, 17:27   #19
Senior - BHPian
 
anachronix's Avatar
 
Join Date: Mar 2006
Location: Madras
Posts: 3,250
Thanked: 1,241 Times
Default Re: Ford Fiesta: Sudden Drop in Fuel Economy

Not yet dude, I had to do a quick trip to Kerala early last week and got back only today. Sending the car tomorrow morning!

Quote:
Originally Posted by vikram_d View Post
So buddy, any updates on the problem and it's solution if any?
anachronix is online now   Reply With Quote
Old 23rd May 2013, 08:04   #20
Senior - BHPian
 
anachronix's Avatar
 
Join Date: Mar 2006
Location: Madras
Posts: 3,250
Thanked: 1,241 Times
Default Re: Ford Fiesta: Sudden Drop in Fuel Economy

UPDATE:

I got a chance to get the car completely checked and I believe now its back to normal. It was like lot of bad things that were happening together in the car that affected the fuel efficiency as well as overall performance.

Listing the problems:

1. The Fuel Filter was dead, when it was tested by pouring some fuel all that came out was a black substance as fuel. I got a chance to speak to a Ford engineer who worked earlier in HotLine Support, told him that there is sudden drop in FE and he asked me to check the Fuel Filter. He also recommended fuel filter change every 20,000KM. The folks at service were sticking to the 60,000KM recommended fuel filter change by Ford.

2. The AC vent for recirculation mode was stuck open as connection to the lever that controls the vent got disconnected somehow. It was connected back, so the car was effectively running on fresh air mode all this time.

3. The AC gas was overfilled, it was adjusted and right amount of gas was filled. This was as Karthik mentioned a few posts earlier was affecting the AC efficiency in the day time and also affecting the fuel efficiency.

4. The AC in fresh air mode, overfilled AC gas put so much stress on the whole AC unit that the car kept going into limp mode with the fan running in hi-speed continuously in the hot summer and the reason for sudden drop in cooling and also the FE. Adding to this a shabby fuel filter brought down the FE by a considerable margin which helped me notice the complete mess and get it fixed!

I have driven the car for about 50+KMs now and the DTE is showing promising numbers which is considerably different from what it showed before all this work was done. I need to do a tank fill method fuel efficiency check and post the real world figures here.

Thank you folks, loads of inputs in helping me resolve this issue and as always BHPians rock!

I should also mention this, the team at MPL Ford, OMR did a fantastic job of investigating the problem. They were working with me like it was a friendly garage, they never had any problem with me sitting with their technicians and understanding every bit of work that is done on the car. Kudos to the team at MPL Ford!

Quote:
Originally Posted by vikram_d View Post
So buddy, any updates on the problem and it's solution if any?

Last edited by anachronix : 23rd May 2013 at 08:11.
anachronix is online now   Reply With Quote
Old 23rd May 2013, 11:30   #21
Senior - BHPian
 
vnabhi's Avatar
 
Join Date: May 2007
Location: DC -> DC
Posts: 5,270
Thanked: 1,235 Times
Default Re: Ford Fiesta: Sudden Drop in Fuel Economy

@anachronix---we are glad to hear that your problem got settled finally. Do update us from time to time about your FE figures.

Now I will check from my service record if my fuel filter was changed or not. I think it must have been, as the 60K kms service was done on my car last year (though it had run only 37 K).
vnabhi is offline   (1) Thanks Reply With Quote
Old 23rd May 2013, 14:01   #22
Senior - BHPian
 
vikram_d's Avatar
 
Join Date: Jul 2006
Location: Bangalore
Posts: 2,380
Thanked: 936 Times
Default Re: Ford Fiesta: Sudden Drop in Fuel Economy

Glad to hear that all the problems have been diagnosed and rectified. Happy motoring
vikram_d is offline   (1) Thanks Reply With Quote
Old 3rd December 2013, 12:31   #23
BHPian
 
Prodigy07's Avatar
 
Join Date: May 2013
Location: Chennai
Posts: 417
Thanked: 249 Times
Default Re: Ford Fiesta: Sudden Drop in Fuel Economy

Quote:
Originally Posted by anachronix View Post
UPDATE:

Hi Anachronix, Of late I have been noticing drop in mileage in my Fiesta 1.6. The figures are pretty low 8.5 to 9. Also, the A/C fan does not switch off automatically. It keeps running even after the ignition is switched off. Once the ignition is switched on, the A/C fan goes into silent mode. What could be the problem? Could you please help me? I have switched from MPL Ford to Bosch Service Centre.

Last edited by Prodigy07 : 3rd December 2013 at 12:33.
Prodigy07 is offline   Reply With Quote
Old 3rd December 2013, 13:25   #24
Senior - BHPian
 
vikram_d's Avatar
 
Join Date: Jul 2006
Location: Bangalore
Posts: 2,380
Thanked: 936 Times
Default Re: Ford Fiesta: Sudden Drop in Fuel Economy

Quote:
Originally Posted by Prodigy07 View Post
Hi Anachronix, Of late I have been noticing drop in mileage in my Fiesta 1.6. The figures are pretty low 8.5 to 9. Also, the A/C fan does not switch off automatically. It keeps running even after the ignition is switched off. Once the ignition is switched on, the A/C fan goes into silent mode. What could be the problem? Could you please help me? I have switched from MPL Ford to Bosch Service Centre.
If the fan is running continuously then the first thing I would suspect is the coolant temperature sensor. If this sensor is not working properly, the fan will keep running because the ECU thinks that the engine is overheating. I would recommend that you get the coolant temperature sensor checked.
vikram_d is offline   (1) Thanks Reply With Quote
Old 3rd December 2013, 13:44   #25
BHPian
 
Firebird's Avatar
 
Join Date: Jul 2005
Location: Mumbai / EC1M 3NH
Posts: 470
Thanked: 61 Times
Default

Quote:
Originally Posted by vikram_d View Post
If the fan is running continuously then the first thing I would suspect is the coolant temperature sensor. If this sensor is not working properly, the fan will keep running because the ECU thinks that the engine is overheating. I would recommend that you get the coolant temperature sensor checked.
Before doing anything check the coolant level. I experienced this in past when the fan used to be on even after switching off the car. The issue turned out to be empty / very little left in coolant container.

Added water as quick fix and bingo, it was solved. Later got the coolant changed.

If this doesn't work then start thinking about other solutions.
Firebird is offline   Reply With Quote
Old 3rd December 2013, 13:50   #26
Senior - BHPian
 
aravind.anand's Avatar
 
Join Date: Apr 2011
Location: Chennai
Posts: 1,378
Thanked: 1,791 Times
Default Re: Ford Fiesta: Sudden Drop in Fuel Economy

As already discussed on this thread till now, to summarize, one has to get these checked -
- Tyre pressure
- Coolant level
- Thermostat and senors associated with cooling system
- Air filter element - check and clean / replace as per requirement
- Fuel filter
- AC refridgerant level and efficiency
- Lastly, ECU reset or re-flash

Just a small checklist from Vikram, Anachronix and other key member's inputs
aravind.anand is offline   Reply With Quote
Old 3rd December 2013, 14:48   #27
Senior - BHPian
 
anachronix's Avatar
 
Join Date: Mar 2006
Location: Madras
Posts: 3,250
Thanked: 1,241 Times
Default Re: Ford Fiesta: Sudden Drop in Fuel Economy

I think you have to check what Vikram & Firebird mentioned, it should be mostly to do with the cooling system. Even if the coolant levels are low, you need to check why the coolant level had dropped if the drop is substantial!
anachronix is online now   Reply With Quote
Old 3rd December 2013, 18:55   #28
Senior - BHPian
 
vnabhi's Avatar
 
Join Date: May 2007
Location: DC -> DC
Posts: 5,270
Thanked: 1,235 Times
Default Re: Ford Fiesta: Sudden Drop in Fuel Economy

AC fan remaining on for a couple of minutes is normal for Fiestas, though it happens rarely. In my trip to Ooty, after reaching my guest house via the 36-hairpin route, the fan remained on for at least 4 minutes after switching off.

Around once a month, it remains on for a minute of so, when the traffic is intense.

But as others have suggested, please do get everything in the list checked.
vnabhi is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
A/C and fuel economy & How to use aircon optimally. Lukeskywalker Technical Stuff 115 15th June 2014 12:09
Sudden Drop in Fuel Efficiency. What could be the cause? ashwin390 Technical Stuff 2 15th June 2011 21:49
Does Weather Affect Fuel Economy wolfinstein Technical Stuff 34 20th August 2009 00:57
Electronic ways of IMPROVING fuel economy Godfather Technical Stuff 8 1st October 2006 08:50
Tyre pressure vs fuel economy sbasak Technical Stuff 15 27th February 2006 23:31


All times are GMT +5.5. The time now is 19:18.

Copyright 2000 - 2017, Team-BHP.com
Proudly powered by E2E Networks