1990 TB42 gas issue

[4X4MUD]

Hey guys, Got a 1990 GQ TB42 and its drinking gas like you wouldn't believe. I have done the plug, leads and air filter and tuned the gas and still same issue. I even adjusted it from the distributor till it pings and then set it right, the top of the air filter is set right and i know the car is running perfect but drinking heaps. Not to sure on petrol how much it uses but its also prefect it drives perfect on fuel too. Is there any tricks you guys might have up your sleeves to help bring it back to 380 km per 80LT tank? Its getting 220 km max at the moment. Nothing has changed and all the mixer setting are also good.

[threedogs]

Can you smell gas, just sounds funny, everything running well but using heaps of gas

[taslucas]

Does it feel like it has the same power or do you find you might be pushing the accelerator down further than before?
Have you measured the timing properly or just doing it by feel?
Is there any leaks in the gas lines?

[4X4MUD]

just by feel but i know its right because its driving perfect... No leaks i hope, Would be a little dangerous I might open up the carb and give it a good clean and then change the air filter just incase its faulty or blocked, rest all the gas and lean it out a little and see what it does.

[Bigcol]

usually around May, they start to put additives into the Gas, so it wont "freeze" in the convertor. then around Sept they take them out

when I had my '89 TB42 Gas/Petty, it was tuned for performance Gas - using Sprint Gas mixer - so it was very very noticeable when they did the winter /summer changes
ended up getting a tune twice a year - late May and early Oct
usually got about 350Kms when tuned, then it would drop to about 300Kms when they f@rted around with it
tuned right, I was getting 96Kw on gas and 98Kw on Petrol

also, with the Gas feed into the Carby, make sure THAT has not been turned open too much - best way to tune them is with a Lambda meter.
first time I got it done for performance, took about 3 hrs to tune and set,
after that, it was a 30 min job to do, as we had the settings

mind you, it also took about 10 different places before I found one that knew what they were doing as well.

hope this helps.....

cheers

[4X4MUD]

Im aware that they add stuff to keep it from freezing but my car went from 400 km to 200 km... Im going to looking into it for leaks or anything like that... somethings not right

[taslucas]

Are you getting enough spark?
Seems strange that the power is the same, (well everything is the same) except the gas consumption has gone up. hmm?

[4X4MUD]

Im sure i am but tomorrow morning im going to slap in a new set of plugs, leads and air filter and then give it a good tune and see what happens... Somethings not right

[4X4MUD]

Guys, I still haven't done the plugs and leads... But i wanted to mention that its been back firing a lot under load and its lots a lot of power. Anyone got any ideas if i change plugs, leads and air filter if it will fix the issue? Its an impco gas system and there not suppose to back fire...

[taslucas]

Back firing may suggest timing issues. Are you sure the timing is set correctly?