20V mixture(fuel/air)problems

[FLESHAXXE]

I have recently changed the head gasket on my silver top 20v,due to an oil leak...I cleaned the piston tops and valve heads of excess carbon deposits....checked clynder walls,movement in pistons....everything went back up ok..timing set at 10deg'.s......however the car was low on fuel and I troubled the airflow screw to see if the high idling would be fixed...but it did not help....the gastank was filled and the high idle stopped.......However when I rev. the car out I"m getting blue smoke,black,grey,white etc...I have tried resetting the air/fuel but I'm still smoking all colors,could my 1 1/2yr old plugs be giving me this as well????

[CozmoNz]

Blue = Burning Oil
Black = Fuel
Gray = a mixture
White = Coolant / Water

Funny... they all seem like something that would be fixd when you do all of the above. You do it right

as for mixture, why did you play with the afm? All your doing is fooling the ecu to thinking theres more air... (or less?) in which youd either run rich or lean, Blue should NEVER come out the exhaust, ever never ever. The amount that comes back from the cam cover is very minimal, and cant be seen. as for white... i really dont know..... Unless the car is cold, it should never be white either .

and how low on fuel was it? like, hard to start low, or just *on E*

[AceSniper]

Blue = Burning Oil
why did you play with the afm? All your doing is fooling the ecu to thinking theres more air... (or less?) in which youd either run rich or lean

The screw is a Bypass for idle/mixture it wont adjust the idle speed, look for vacume leaks, stuffed thermostat, stuffed idle up. asuming the nex H/G is all ok

[10k 20v]

if an engine is running too rich it will burn oil and smoke blue smoke as well as grey and black, it's called bore wash,

hey, also as acesniper said, check the simple things first, can often be the simple things that always get overlooked, have you considerd check cam timing?

[FLESHAXXE]

I will check cam timing as well as piston compression to see if there is a big difference in each clynder....then I would know also if it is the compression rings that have been worn......also I have changed the sparkplugs..the one I took out were very black ...

[FLESHAXXE]

Took out sparkplug #4 ...oil on the tip .............look onto the piston head and there is oil..went home check lines after the AFM,and found an air leak,changed oil and filter,sealed leak...car is smoking even less,furthermore you're seeing flames in the tail pipe..however I still want it to burn clean ..any suggestions??????

[Mr Revhead]

not that is going to help the smoke, but run the timming at 8deg, prevents the konck sensor pulling it back too much

[Loudtoy]

Took out sparkplug #4 ...oil on the tip .............look onto the piston head and there is oil..went home check lines after the AFM,and found an air leak,changed oil and filter,sealed leak...car is smoking even less,furthermore you're seeing flames in the tail pipe..however I still want it to burn clean ..any suggestions??????

Basicly you won't get it to burn clean all the way through with a silvertop, unless you go with an aftermarket computer that can adjust fuel maps and ignition all the way through the rev range and throttle positions - reasonably expensive just to get it to burn clean me thinks.
Chuck a gas analyzer or lambda link (is it a lamda link guys) up the exhaust tip and put the thing on a dyno, if it's the same as my old silvertop it will run rich 2-3500rpm lean from 4-5800rpm and then rich from 6k till rev cut. All the numbers in between that i haven't got are transition periods between rich and lean - all this in a standard computer to!
The only way to make it look like a clean burn is to tighten the spring on the afm flap, thus making the computer think that there isn't as much air as there is so leaning the mixture out - clean looking burn tho it will be really lean through mid range and not bad elsewhere. Personally i'd rather go the other way and have a safe mixture throughout - even if slightly richer down low.
Note for some reason it wasn't any richer p top after the spring tension on the flap was reduced slightly, have a feeling this was due to the flap not opening fully under full throttle when it first went in so the larger volume of air at high rpm's may have ahd something to do with it!

Doubt this helps much but hope it's got a little usefull or at least interesting stuff in there

[sergei]

Yep, same problem running lean in 4000-5000 rpm range, even with Mines ECU, it is something to do with AFM, the best way is to invest in aftermarket ECU (not just plug in replacement, or piggy back) get rid of AFM, use MAP, tune it properly, and you probable will get some more power out of it aswell.

But other thing might be just injectors, find a set of good injectors (they are not expensive - $50-$100) preferably black top or face lift silver top model.

I had a mixture problem because of injectors:
Black smoke (lots of it)
Real rough idle
Detonation in mid range (a lot of it)
Black plugs
Etc.

BTW there are 2 types of injectors, I have 4 sets of them, 3 sets are bad, all fo those 3 sets have 2 holes on tip narrower (closer to ceter) then in good set, part number is the same.

[sergei]

Oh yeah, I forgot to mention that injector O-rings on those are real pain in the ass, you can't reuse old ones , as they will brake and leak into manifold, the new set is about $40, go to Engeneering Plastics, if you are on the shore, ask for Viton O-rings, you will have to come with injector and old O- rings, the Viton stuff is better then they sell in Toyota (from my experience), but only the middle 2 have to be Viton, the top and bottom (which are not O-rings but some sort of rubber washer, but you can use fat O-ring instead) can be a regular rubber. Viton is usually green colour.

[CozmoNz]

built yourself an A/F *guage*

stick it in your car, and see excactly what its doing

[Loudtoy]

built yourself an A/F *guage*

stick it in your car, and see excactly what its doing

But but not accurate enough i had an af gauge in my car before and after the afm was played with and the thing didn't give enough indication of what was happening and you have to have 3 eyes as well, one for the road, one for the rpm's and one for the af gauge. I personally don't have 3 eyes, but if you do go ahead and see what you find, i'm sure it will be quite different from what a dyno graph with af overlay will show. I have tried it from passenger seat and with passenger watching af gauge and it never quite works out. This is with an autometer gauge as well not a home built jobby. Also when a dyno run cost's roughly $60 with af's thrown in and a guage cost's roughly the same (yes even a home built one, work it out) you may as well get the dyno run, then you also have a start pont for power to increase it - if you want to!

Just my opinion however if you want to build a af gauge go ahead but don't expect it to show you heaps more than what you already know.
BTW Don't ask me why i have an af gauge it's a long story about stuff that you will be bored out of your tree from

[FLESHAXXE]

Went by the mechanic today..the distribitor was to far foward....timming was at 20deg's : he said that he will fine tune it and see what happens from there....have to go for the car this afternoon..THANKS GUYS ....will keep you posted ...