Emission Control Computer

[malooney1974]

Does anyone know if disconnecting the Emission Control Computer at the wire harness will have damaging effects of any kind. The engine seems to be running fine but I don't want to cause any damage.

Thanks.

 

[malooney1974]

Forgot to mention it is in a 83 FJ60 with all stock smog equipment.

 

[Randy88FJ62]

FJ60's have a "computer"?

 

[malooney1974]

not really a "computer" more of a "unit" with simple circuits that controls various aspects of the emissions system. It is located on the drivers side under the kick panel.

 

[Fast Eddy]

Why disconnect it?

 

[tucson_sailors]

Emissions box

I have replaced mine (84) with one out of a later model (86) since I was having the dreaded "60 stutter" which is probably the fuel cutoff valve on the carb intermittantly being activated because of that box.

It's easy enough to disconnect the box and verify if the 60 runs - but I can't say if your rig would have emissions issues. I know that the fuel cutoff can be bypassed, but the FSM shows additional things that box does, but its easy enough to try and then put back if bad things happen.

Let us know - those boxes flake out, and if they can be bypassed or removed without issue its one more think to keep our dinosaurs on the road!

Glenn in Tucson
84 FJ60

 

[malooney1974]

All smog equipment is jacked-up. Giving all sorts of afterfire problems and holes in the egr system. Removed the "computer" from the loop, (disconnected the wire harness) and the cruiser runs like a new machine. All hesitation, stumble, afterfire, problems are gone. Even getting slightly better gas milage. Just don;t want to cause any damage by leaving the smog equipment hooked up but removing the computer. Any ideas about this?

Thanks.

 

[malooney1974]

Thanks for the response Glenn. So far so good. Just removed it yesterday and the machine is running so smoothly. I will start to systematically remove equipment controlled directly by the computer and see how she continues to run.

 

[tucson_sailors]

Smog state or not?

Thanks for the response Glenn. So far so good. Just removed it yesterday and the machine is running so smoothly. I will start to systematically remove equipment controlled directly by the computer and see how she continues to run.

The other important question is if you are in a smog state (I am) and therefore cannot remove that garbage. I would also suggest if you have a clean smog setup thats working, to box it and see if fellow mudders in states like mine are willing to cross your palms with some of that folding green stuff. There are enough folks that buy rigs from non-smog states that have to put the stuff back together to make it worth your time while desmogging to put known working bits aside.

Glenn

 

[malooney1974]

I currently live in TX which requires no smog testing but am planning a move to CO soon and am fairly sure they do require the testing. Does the smog equipment really help to pass such tests?

 

[Zack1978]

PM Jim C....He is the guru about all things Land Cruiser.


Zack

 

[rusty_tlc]

FJ60's have a "computer"?

Toyota calls any solid state control device a computer. The emission control "computer" is just a collection of logic gates, AND, OR, etc. I call it a state engine.

 

[Gurr]

Ha, I tried disconnecting it last night to see what the difference was and my truck wouldn't run without feathering the gas.

 

[FJ40Jim]

The emissions computer runs the fuel cut solenoid on the carb (amongst other things). Just disconnecting it will kill the idle and make it run like poo generally.

If disconnecting the box makes the truck run perfect, then the box is not the problem.

 

[malooney1974]

I isolated the problem to the VSV1. The valve opens and closes fine. So I have concluded that when the valve is open and allows vacuum through I start to get all kinds of afterfire and popping sounds through the exhaust. I tried just unplugging the VSV1 and plugging back in the computer and the truck ran poorly. If I leave the computer unplugged I have a truck that runs very well and gets slightly better gas milage. I did have to adjust the carb. though.

Any ideas why it would run better without the computer connected?

Thanks.

 

[Gurr]

Does it run better both cold and hot? I think that answer would narrow the list...

 

[FJ40Jim]

Any ideas why it would run better without the computer connected?

Vac hoses misrouted somewhere.

 

[freepowder]

Vac hoses misrouted somewhere.[/QUOTE

What happens when you've a totally de-smogged motor running a Trollhole non-smog world carb and recurved (by you) dizzy?
Would you be able to discon the 'computer in that case?

 

[LAMBCRUSHER]

as long as the green wire mod has been done, the comp can be bypassed. if the wire mod has not been done, and the idle solenoid is still operated by the comp, then the rig won't idle unless the carb is way out of tune. the THC carb should work just fine with the green wire mod(landing the ground of the solenoid circuit directly to ground rather than letting the comp send it a ground...) the rest of the emissions system should be correctly desmogged to bypass the comp. and yes, those smog pieces are the ONLY way one of these engines will pass an emissions test- but they all need to be functional and tuned properly...HTH

 

[Spike Strip]

If he's running a Trollhole carb it only has a one-wire ICS and is grounded through the carb body. The computer then is only taking up shelf space. Send it to me, I'm in Kalif and need it as I am trying to get a pile of them together so I can have them tested/fixed for the Kalifornicans that need them. A properly functioning EC makes a big difference when trying to pass smog with a stock motor.