Idle issues?

[timemachinetercel]

Hi there!

I have recently become the proud owner of an 84 SR5 with 140k miles..
I have owned the car around a month and it's just awesome..
I have noticed that recently my idle is surging and dropping but it only really seems to do it when the car is warm and when starting it warm.. (If that makes sense?) When you drive the car from cold and don't turn it off generally speaking it idles okay..
I have changed the plugs, wires, cap, rotor, air filter, fuel pump and filter. I have been looking around at the Vac hoses as well (There are so many!) Using Carb cleaner but I haven't noticed any change in Idle in doing this.
I have replaced a could that looked a bit old but even with all this it still won't idle well. Lately it has been surging more than dying..

I have owned a couple of older cars now and I enjoy the challenge and am just learning as I go!

So if anyone has any ideas, I would love some help!

Thanks!

[dlb]

welcome to the forum, TMT.

sounds like a vacuum leak to me. try sucking on hoses that go to each vacuum diaphragm, make sure you cannot suck air through. if you can, that diaphragm is ruptured and is a vacuum leak. for other devices like the charcoal canister, you can disconnect and plug the hose that goes to that device and try driving like that for a while to see if it is the source or your problem.

[timemachinetercel]

Thanks for the reply!

Vacuum diaphragm? Just try all of the Vacuum hoses and suck on them? Or just the one's running to and from the carb?
This is all very new to me so I apologize!

[lannvouivre]

Suck on the hoses going to and from the parts that look similar to this:

This one's a random one off the web, but all diaphragms have a housing similar in style to this.

[timemachinetercel]

Fantastic! Thanks!

If it ever warms up here I will take a look!

[rocketscience]

It'd also be a good idea to confirm that all of the vac hoses are actually routed correctly too. You can find a diagram either on the underside of your hood or in the FSM posted here viewtopic.php?t=8323. I was having timing issues related to the vacuum advance on the distributor and traced my lines to find that many of them where misrouted, maybe 8 or 10? It still ran okay with em like that but was much better afterwards, fixed the advance problem and didn't take very long, probably 20-30 minutes.

Tracing them also makes them seem a lot less complex and foreboding.

[dlb]

Tracing them also makes them seem a lot less complex and foreboding.

i agree. an easy way to determine which hose goes where is to disconnect the supposed start and end points for a hose and then blow through one end. if air comes out the other end, it's going to the right place.

this especially helps when it comes to trying to trace the metal lines that the hoses attach too, between the carb and the valve cover. that thing is a pain to try to follow.

[timemachinetercel]

Holy cow! 885 pages of a manual..
That's awesome.
Any idea which page the Vac diagram is on?
I will have a good look through anyway..

[timemachinetercel]

Is this a good diagram to follow?
http://www.toyotapartsoverstock.com/ima ... A5997C.jpg

[dlb]

there are colour-coded vacuum diagrams here, i think in the guides section.

the emission section of the FSM starts somewhere around page 80.

[Petros]

that vacuum diagram in the link is for the 49 state federal emissions car that also has the altitude compensatory. If your car is from California or does not have altitude compensation, this diagram is not correct.

[timemachinetercel]

Thanks again for all the help guys..
I will continue to go through the online manual.

[timemachinetercel]

Its seems as if the idle issue is getting a little worse.. I haven't had time to look at it yet.
It is also dying at stops when not fully warmed up.
Still a vacuum or fuel?

[lannvouivre]

Try spraying the lines and such with carb cleaner while the engine is running. If you hit a vacuum leak, the idle speed will change.

[dlb]

is the fast idle screw set correctly? choke valve closed when cold, wide open once warmed up?