Fuel consumption down from 30 to 22

[SilverVti]

Hi

  I've been running my Vti from new in 1998 and have tracked fuel consumption since the start (yeah I know ). Fuel consumption has consistently averaged 31/30 from the start until a around 2-3 years ago when consumption dropped gradually to 23/24 mpg where it has remained ever since.

  I've not done a lot of miles in recent years but it's been used regularly. I did reset the ECU in 2010 but it made no difference.

Any suggestions on how to restore fuel consumption other than to check plugs and get a new engine ??

Thanks in advance.

SilverVti 

[dr_broon]

Hi. Fair play in having her from new

 

Have you had it serviced recently? Fuel filter etc? How many miles is on the clock?

[SilverVti]

1 hour ago, dr_broon said:

Hi. Fair play in having her from new

 

Have you had it serviced recently? Fuel filter etc? How many miles is on the clock?

Thanks for the responses....  

I have loved this car every minute I have it! 

So i have replaced both rear brake cylinders and pads and fairly recently had a slow puncture that may have both had an impact,  but fingers crossed at the moment I don't suspect any remaining issues -  but good suggestion. 

It's done 103k, with the bottom block being replaced at 30k (under warranty thankfully).  

Not thought about fuel filter but it still goes like s*** off a shovel,  so don't think it's not getting the fuel

I've just taken out the coil pack (2nd time to replace it),  so I guess an air filter and plugs won't go amis while I'm doing the pollen filter. Perhaps give the plugs a clean/gap check. Any suggestion on cheap parts welcome. 

 

How would the bearings be noticeable other than MOT "twerking"  and shuddering at speed (both ok)? 

Thanks

SilverVti

[dr_broon]

Wouldn't worry about the engine then... It's a spring chicken!  103 is nothing really... Mines got 190 and still going strong - just change the oil every 6 months and you're laughing. 

Air and oil filters, plugs and oil, and see where you are after that.

[Gel]

If your fuel consumption doesn't improve after all the checks and maintenance suggested ......your best to change the HT leads, distributor cap and rotor........last but not least would be to replace your oxygen sensor.

 

Be sure to reset your ECU once you fit the service parts.

 

Good luck

[SilverVti]

Thanks for the tips guys. The pollen filter is now brand spanking new and the changed resistor pack has restored the fan to normal !  

 

I've just been looking through he service manual and notice that there is an adjustment for the idle speed setting. I think I may try and check this at the same time as changing the plugs and oil. 

 

On the subject of oil, I'm planning on 10/40 - any thoughts aside from buying some pixie dust synthetic stuff (that I won't be tempted into doing by some marketing speak ;-))

 

Re plugs, I have been playing with eurocar parts site today and have a dilemma. They state either  

Bosch 0 242 229 576 AKA  Bosch FR 7 LCX+ which I believe is also known as the NGK 4291

or 

 Bosch 0 242 235 667  aka Bosch FR7DCX+ which i believe is also known as the NGK 7121

Apart from the aforementioned sprinkling of pixiedust relating to kryptonite benefits of space ready precious metals, is there any real difference between them all ??? (you may detect a large portion of cynicism/sarcasm as you may have gathered I'm not that partial to marketing bulls**t when it comes to spending anything other than the bare minimum unless there's a real proven advantage).  (and I've had a glass of wine)  

cheers !

[dr_broon]

I always go for Bobby basic ngk ones

[SilverVti]

So in the end I went with Bosch spark plugs -  FR 78 X  - they have 4 electrodes at the tip - only cost £13 from euro car parts, some Shell Helix 10-40 oil, a bosch oil filter (somewhat of a nightmare getting Euro car parts to supply the correct one - they supplied the wrong one twice mistakenly giving me a 1.4/1/6 first then a type R next.) I also treated it to some oil flush. I then did the ECU reset using the excellent guide. After this lot and the air and pollen filters I'm hoping it'll goes much better  ...... or my right foot is heavier. 

Or maybe the oxygen sensor is next combined with leads, distrib cap and rotor .... do these actually have a rotor arm these days ? 

 

Ta for the tips. Lets see if the fuel economy improves.

[dr_broon]

Good stuff. Yeah, we're still rocking rotors

[SilverVti]

So a few weeks down the road after replacing oil, filter and spark plugs it seems more responsive. I had the aircon done today for £22 at ATS vua a groupon deal. 

 

I've not yet done enough miles to check if consumption is any different. My local friendly MOT tester did an emissions check today and the lambda reading was fine but CO output was too high. His suspicions are the cat converter is shot and this will lead to low fuel consumption and higher emissions. Does that sound right  ??.

The back end is several years old and probably ready for the skip so I'm thinking of replacing the cat and everything behind it. Any suggestions for compatible parts peoples ?? 

I'm looking for cheap as opposed to performance, and not interested in removing bits like the cat if they either need to be taken off or fiddled with for an MOT.

 

Oh and by the way, I've noticed this went for £1800 - it's even tidier than my one by the looks of it. Did someone here buy it ? http://offer.ebay.co.uk/ws/eBayISAPI.dll?ViewBids&item=291785817754&showauto=true  

 

[Dexter]

I failed MOT due to high CO and the path lead to a burnt distributor cap & rotor.