Throttle body filthy after a month - Ecotec

[savage1987]

My parents' Ecotec VY 1 Tonner is having some dramas.
The throttle body was cleaned up a month ago and I just had to do it again because so much sh!t had built up in there that it was sticking closed a bit, as in very stiff to start driving.

Intake side was fine as usual but the engine side (including butterfly) was coated in about 1mm of black stuff, with the coating on the edge of the butterfly causing it to stick. I cleaned it meticulously and put it back in, but I'm betting it'll do it again in a month. This really shouldn't happen.

The fuel economy has also been horrendous lately, for a V6 auto to average 15-16L per 100km on the highways is just wrong. My 5L does that around town in traffic! Speaking of, also took my 5L throttle body off to compare, this one hasn't been cleaned in over 12 months and 50,000 km, it was still fairly clean.

Our mechanic is pointing the finger at the injectors and there's a bottle of cleaner in the tank now. He also suggested it could be that we've been using Caltex fuel (synthetic additives or something) but I'm not convinced. Mum said she'll switch to using Shell premium now but this shouldn't make that much difference should it?

Anything I can check on the motor to see if there's a problem somewhere else? Would replacing the plugs and leads make any difference? I really don't know what causes things to go bad in an Ecotec, just that they often seem to!

Sam

[Emackulation]

I only use Caltex, never had it before. I duno what could eb causing it though, got me stumped.

[vlv8vic]

mine would get gunk, gets a lot less now using premium fuel... I'm sure that isn't the final answer inthis case though. seems a tad severe.

[savage1987]

It does seem severe. Anyone else have any suggestions? I will check again in another month or so and see how we go.. could be that the mechanic didn't clean the TB a month ago, he only 'cleaned' it. Possible, but I think he's more reliable than that.

Sam

[FPV 4 T]

do you use an aftermarket air filter?? eg: k&n?? coz if you do it could be that you are over oiling you air filter... and also check to make sure there is no gaps in ur air intake pipes as that could be sucking in dirty air and road residue...

[andyman]

check that the egr valve isnt stuck open, check the pcv valve,

it would be a good idea to remove the injectors, have them ultrasonically cleaned and then install a fuel filter in the fuel line just off from the tank, because for some reason the crewmans and one tonne didnt have a fuel filter,

on a side note ive found my car dosnt run as good on caltex and woolworths fuel is imported from overseas, well in our town it is, so i dont touch it and neither does anyone else i know

[savage1987]

yeah we're running shell 95 through it now, no it's not running a K&N or anything like that. Just a stocko paper filter.

What's the ECG valve? I'll check the crankcase ventilation one when I get a chance (parents' car).

Also, seems odd they don't have a filter, can anyone verify this? I'd look but it's dark. I just find such an oversight by Holden hard to believe..

Sam

[BANKS]

no fuel filter? how could they leave that out?! thats just asking for trouble

[savage1987]

That's what I thought. Seems crazy to me.

[greenfoam]

The reason they get dirty in the first place is from the smoke comming out of the crank case back into the throttle body, good engine = clean throttle body. It sounds like the rings are very worn or some broken in that engine to be getting such bad blow by past the rings to make that much carbon so fast in the throttle body. Suprisingly considering the sludge inside the engine on my VP the throttle has stayed mirror clean for 2 years. If there's no fuel filter on it well everything will be worn out allready from dust getting in

[andyman]

it is weird that they dont have an in-line filter, as far as i know they only have a pump strainer, which everthing else has

[WAGON MAN]

then install a fuel filter in the fuel line just off from the tank, because for some reason the crewmans and one tonne didnt have a fuel filter,

The fuel filter is in the tank.

Refer to the fuel filter thread.

[savage1987]

oh damn that's going to be a pain to replace.

Discovered today that it was a period of much more than a month, yet surely no VYs should be old enough even without a clean ever to build up that much deposit. It was 2mm thick! The mechanic never removed the TB, just sprayed carby cleaner in while the motor was running. Cheap..

Either way I'll have another look at it one of these days because the thing is still chewing the fuel. Could that just be the higher diff ratio in the Tonner??

Sam