Hey guys im really hope somebody can help me out and point me in the right direction as im really getting down about the cars situation.
my car is a 06 Vectra facelift 1.9cdti 150(mapped to 170 aparently) 67,000 on the clock
My MPG is poor,at the moment im getting 28MPG around town and only a couple more MPG on a motorway run.I have done several different ways of calculating my consumption and they all come up with roughly the same results(give or take 1 or 2 miles).
My problems started after my alternator died on me and i replaced it with a new one.Since then the fuel consumption has risen and ive noticed that the fuel light comes on alot earlier than it used to,after ive put fuel in it can take up to a mile or so for the light to go out and the needle to settle on the correct level.The BC seems to be all over the place,sometimes the "range" doesnt go up when i put fuel in so after a few miles its sat on 0 untill i fill up next.When the range does work it will say for example 75 if i put a tenner in but by the time ive driven a mile or so its dropped by 6 or 7 miles and keep plummeting untill i have to fill up again.
I did have the spanner light start to come on for a few minuted of driving about 3 weeks ago so i brought a RAC fault code reader from argos(i know its not brilliant but it does the job) and it came up with a glow plug fault so i took them all out and got my mumtimeter on them and 1 was completely dead so i replaced it and rest the fault code and its never come back...touch wood.Apart from the 1 time there have been no lights on the dash and the car is running good.
I have checked various things including any fuel leaks,splits in hoses,correct tyre pressure and even gave her a mini service whihc included and oil changed and new air filter but still no difference.The swirl bar is still attached and working correctly.The EGR has been cleaned twice in 2 months(inc the solanoid) so has the boost sensor.i put a bottle of redex though it aswell to no effect
I have had 1 thought that could be a possable cause and thats the MAF,basicly the car came with a panel filter and modded airbox,the air box had the top half of the funel taken off and also some large sesctions cut out to aid airflow and give that awsome GGRROOOOWWWLLLLL which i love.When sthings stared going wrong with the car the first thing i did was blank off the holes in the box with some fibreglass as i thought that maybe too much air was getting in and over fueling the car but it didnt make any difference.I then decided to clean the panel filter which was dirty as hell and saturated with oil(recharge oil not engine oil) so after about 4 different cleaning products and about an hour leant over the bath it was clean.Wheil doing the filter i also took the MAF off and inspected it,it was totaly gunked with the recharge oil and had a 1mm thick layer all over it.I know this isnt a good thing to do but i gave it several squirts with carb cleaner untill it was clean...i know there was a chance it could damage it but i thought ive got to try it.Again this made no difference to the MPG situation.I did think that it maybe be faulty and givving a faulse reading causing the car to overfuel but not sure if the fault light would come on?
My thermostat is faulty i think,its getting to about 85 if im plodding around town but wont sit there for very long before it drops to 70 and fluctuates between the 2 tempretures.I know this can make the car run cold and over fuel it but my mate has the same car as me and his stat is completly goosed and doesnt even move and he still get loads more miles than me doing the same journeys.
Could it be the 3rd injector wiring maybe? i have noticed that the revs are ever so slightly jumping(about 50-100rpm) and on a cold start the whole car will shake 3-4 times in 30 seconds before i pull away.I did have a missfire/hessitation at about 1700rpm but it dissapeared when i put the OEM air filter in.
There is also smoke when i put my foot down,ive never noticed it before mainly due to me having tinted windows but my mate noticed it when he was following me and seems to be at about 2500rpm.
Has anybody got any ideas what it could be,im really fed up now and its costing me a small fortune in diesel which i wasnt expecting as i changed from a petrol due to the amount of miles i do.It getting to the stage where i cant afford to run it
Thanks for reading and any suggestions will be greatly recieved.