How many 3FE'rs with Rough Idle? What are the fixes?

[alkaline747trio]

Every time I think I have solved my rough idle, it comes back. Looking at the 3FE group and here, it seems that 3FE's are prone to developing a rough idle, so what are the fixes? I want to say that I have tried everything short of signing my life to CDan for almost a completely new 3FE.

 

[v8tuff]

<------subscribed.

I am so sick of shifting into neutral or park when I come to a stop so that my idle will get "less horrible."

I currently idle at 600 in Drive when stopped. If in neutral or park it goes up to 650-700 but still oscillates. I am replacing my 02 sensors this weekend. I suspect it is my main prob.

Check out all your vacuum lines, pcv, run FI cleaner gas additive for a couple tanks. You could do that and not have your problem fixed, like me.

 

[alkaline747trio]

I did a de-smog and got rid of a bunch of my vacuum issues, but it didn't solve everything. PCV was drilled out and I have old school V8 style mini-filters. Have gone through over 5 cans of SeaFoam in the crank, in the oil, and in the gas. Everything helped, but just enough to notice it.

 

[RockDoc]

I think I cured my last bout with some injector cleaner and highway running (was idling well, but had a rhythmic miss). Next up is a throttle body pull and clean. Dealing with a high idle issue after playing with my timing.

 

[Cabrito]

I have a slightly rough idle but have been told that it's normal - it's been the same for the past six years that I have had it and has not gotten worse.

 

[chicago]

Spark plugs?
These engines are finicky about the plugs....
Just a suggestion, cuz I put platinums in mine and it idled for SH*T...put the cheap ass NKGs back in...purred like a kitten.

Chicago

 

[ducatiman81211]

I too did the de-smog and noticed a much better idle, and some of the weird noises went away.

 

[cruiser88]

This guy has did just about everthing under the son to fix this thing. I still say it is in the hareness somewhere. You know i do know where a 80 like yours is for sale for 1500 bucks in monroe co. wv if you need the hookup

 

[alkaline747trio]

I checked every millimeter of that harness when I had the head off...pulled off the wire loom and it all looked and felt brand new! I'm running factory Toyota plugs at just slightly over factory gap, .001 over maybe.

 

[brownbear]

I've got new plug(oem) and have a cold idle roughness. Bounces up and down horrifically.

Soon as it gets warm it's much better.

Odd, putting on the AC brings the idle up to a point where it is smooth. Not that I want to do that all the time.

I found an improvement oddly enough yesterday when I installed a new thermostat. No freaking idea how that would do it. BUT I did notice it has two vacuum lines to the thermostat housing.

 

[DSmolj]

I put a fuel pressure reg. in solve my problem

 

[90FJ62]

i have the same shutter at idle. it is almost rythmic. have tryed different drands of plugs, wires injector cleaner and am about to try rebuilding the motor.
maybe a 2fe time...

dave

 

[mtb_rider]

Spark plugs?
These engines are finicky about the plugs....
Just a suggestion, cuz I put platinums in mine and it idled for SH*T...put the cheap ass NKGs back in...purred like a kitten.

Chicago

Platinum plugs have a much higher resistance than copper, take more energy to fire. Our old ignition systems, or any ignition system not designed for platinums for that matter, can't run them efficiently, and you will get a weaker spark or even a miss at idle.

 

[alkaline747trio]

The idle is worsening now, maybe due to the elevation I'm back to. But now it will actually die on me if I don't keep on the throttle slightly.

So it seems that I am back to where I was this summer messing with AFMs and what not. I'm tempted to take it to a Toy dealership, but I imagine they wont touch it with all the smog stuff gone.

 

[cruiser88]

The idle is worsening now, maybe due to the elevation I'm back to. But now it will actually die on me if I don't keep on the throttle slightly.

So it seems that I am back to where I was this summer messing with AFMs and what not. I'm tempted to take it to a Toy dealership, but I imagine they wont touch it with all the smog stuff gone.

There is ground wires going to the intake,do you have them hooked up? You should see 2

 

[alkaline747trio]

Now that I'm back at school, the LC isn't conveniently parked and I can't go check. But I do know that I have one ground in the wrong place. I assume it isn't the problem though, because before I did the head I had had the EXACT same symptoms. I'm not sure what changed while doing the head, but it definitely seems electrical. Like a short or bad ground.

 

[cruiser88]

Now that I'm back at school, the LC isn't conveniently parked and I can't go check. But I do know that I have one ground in the wrong place. I assume it isn't the problem though, because before I did the head I had had the EXACT same symptoms. I'm not sure what changed while doing the head, but it definitely seems electrical. Like a short or bad ground.

Yea that one that hooks up around the intake(close to where the cold start injecter line goes in down at the bottom) will cause problems if it is not hooked up. I believe the thing takes a 10 mil wrench and part of it may be green.
There is another ground in that area also. Get back to me if you need to know where it is at later.

 

[alkaline747trio]

It is hooked up, but I put it in the wrong place, I noticed it yesterday when I was messing with my vac lines and it is still grounded the same as if it were in factory location.

I'm thinking it's more on the ignition side, because the last time I had this issue...messing with the plug wires got it back smooth.

I did a tune-up on it two years ago, so I'm going to assume that's not the problem. Coil/igniter are stock, and used replacements didn't change anything. Other than completely re-wiring the damn thing, where do I look?

 

[cruiser88]

It is hooked up, but I put it in the wrong place, I noticed it yesterday when I was messing with my vac lines and it is still grounded the same as if it were in factory location.

I'm thinking it's more on the ignition side, because the last time I had this issue...messing with the plug wires got it back smooth.

I did a tune-up on it two years ago, so I'm going to assume that's not the problem. Coil/igniter are stock, and used replacements didn't change anything. Other than completely re-wiring the damn thing, where do I look?

Have you ever tested each and every terminal on the computer? There is a test for it in the fsm. I know it is a pain in the ass but that is what i really think your looking at. And if you get a wrong value on one circit you know where to start.

 

[alkaline747trio]

That is one of those things that I doubt I have the patience for...but I may end up trying that over Thanksgiving.