high fuel usage

[ebay king]

hi guys just joined the forum my wifes got a 93 petrol tarago manual we run all our cars on 98 bp ultimate we bought the car about 3 years ago we were getting 550k's from a tank and no its dropped to around 350k's big drop had our mechanic look at it and found that the 02 sensers were shot so put new ones in but hasnt done a dam thing to it mine also has the black soot on the back door also the auto choke doesnt seem to work until i give it a rev or to after i start any idea on what might get the fuel consumption back waste of good 98 fuel im putting in it sorry forgot to mention its been like this for about a year now thinking of giving it to toyota but dont want to fork out to much cash to them when i could do it myself just want to know where to start looking

[Ozzcaddy]

Have you had the Tarago tuned lately, replace plugs, air filter, fuel filter. Did the mechanic who changed the O2 sensors, do any other checks such as compression test. Just throwing things out there for you to think about.

[ledgend]

if you have done all diagnostic tests and all seems ok go back to basics. check electrical connectors, for breaks or damage, has the condition of the exhaust system been checked ie blocked catalic convertor, or muffler system , check all vaccum fittings for condition ie perished hoses ,check all ported vaccum fittings, gheck throttle and choke linkage for ease of movement, is the choke adjusted correctly , or is it damaged