Erratic idle and stalling at stops (1 Viewer)

[Traakon]

Well if your pump is turning off and on you would be stalling

Agreed but if the pump was shutting off no amount of throttle exercise would keep it running. It stalls when you throttle lift and don't catch the RPM plunge. And it does not always stall, it will sometimes catch the plunge and then chase the idle between 300 and 1000 rpm.
The relays sound like a decent "just 'cause" item on a 24 year old vehicle.

 

[ajax1]

Ok I understood that you would be driving and it would die, I'd replace both relays like you said at 24 years old they have done there job for you

 

[ajax1]

So first thing it list in fsm is iac valve, then egr, then afm, then emc

 

[Traakon]

So first thing it list in fsm is iac valve, then egr, then afm, then emc

The only item on that list not replaced is the Idle Air Control and the one I have tests good per the two procedures in the FSM. For nearly $700 I am not replacing it unless I know for certain it is bad and per the FSM it's not.

I also checked with my Toyota place when I was there picking up the Booster check valve and line and the Circuit Open Relay is $127 and the EFI relay is $12. They showed two different PN for the first so i need the number off the one in my 'cruiser to make sure of the the right one.

 

[ajax1]

Iac from Yota is round 400 online if you unplug it then start your idle should bounce around big time

 

[ajax1]

Have you checked all your vacuum lines including underneath top manifold, did you replace vsv for egr? Have you tried just loping off the egr vacuum lines so it's not on?

 

[Traakon]

Have you checked all your vacuum lines including underneath top manifold, did you replace vsv for egr? Have you tried just loping off the egr vacuum lines so it's not on?

All the vacuum lines checked and double checked. Replaced the VSV when I did the EGR.

It all keeps leading me back to the IAC and it looks like i may have to bite the bullet and order one even though the FSM says this one is within spec.

 

[ajax1]

you have also clean the throttle body thru where the iac bolts in make sure no carbon plugging there, and also the manifold where egr bolts into and the passage that goes to the egr by where throttle body bolts on , also the thru line where the egr vacuum line runs to the egr, it is a thru line that is by brake booster other end is under the manifold , that metal line also usually has bunch carbon, and if you pull top half of intake manifold clean the manifold also

 

[Traakon]

Yes, yes, yes, yes...and yes
What I have not done is pull the entire intake assembly.


The 89422-35010 Water Temperature Sensor will be here Monday and the IAC will be here by mid next week.

 

[Traakon]

Installed the PN 44730-28010 Vacuum valve on the brake booster along with the new PN 90480-24015 grommet and PN 44773-60150 manifold to check valve hose. Now all that area is verified tight and no vacuum leaks.

I would have never thought it but it seems that this did the trick. Put about 50 miles on it and it is back to running perfectly.
Either a vacuum leak in/around all the old joints or a bad vacuum booster check valve...replacing all those associated items did the trick it seems.

Now, what to do with a new IAC

 

[MDarius]

Congratulations!

 

[Traakon]

I think what I am learning from the last couple drive-ability issues with the 'Cruiser is:

Review all the possible causes, find the one I think is least likely and least expensive and start there first.

 

[ajax1]

Glad you fixed it

 

[Traakon]

OK, I just have to laugh at this point.

Drove the 'cruiser for 2 weeks and it ran perfectly, as of Friday, back to acting up in exactly the same way again.
I swear this thing has a remote connection to the parts department at Toyota that tells them when I need to bring my wallet in for a
Benjamin-ectomy.

Going to install the new IAC tomorrow and see what comes of that.

 

[ton504]

Have you done any recent work that required removing engine ground wires? If not, I would still check if they're tight/clean.

 

[Traakon]

Have you done any recent work that required removing engine ground wires? If not, I would still check if they're tight/clean.

Thanks for the suggestion. I have indeed been over all the grounds and repeat doing so every time one of these oddball issues arises. The only "ground" related thing I have not done is actually replace the positive and negative battery cables on whole. That is on the schedule of "To Do" items but I end up chasing these other issues instead.

I will install the new Idle Air Controller (IAC or as the box calls it "Idle Control Valve") PN 22270-66010 tomorrow mainly because it was one of the suspected culprits when this began and I have already spent the $450 on it. I also have the PN 89422-35010 Water Temperature Sensor on the bench as yet another of the possible culprits.

 

[Traakon]

Installed the new IAC and it is once more running very well and will idle properly. Did that fix it, history says I need to give it more time for a final verdict.

In the "Oh looky there" category...the low oil level light came on today. Stayed on for about 2-3 minutes then went out and did not return. Got the girl home and let her sit for 5 minutes on the level drive and checked the oil level...completely full. Not mid point, not almost full but to the "Full" line. My wife says she has had that happen once or twice before but it always had oil pressure (as it did this time) and never lasted more than a minute or so.

Looks like another trip to Mr. T's Parts department for a new sensor may be on the agenda.

 

[MDarius]

Installed the new IAC and it is once more running very well and will idle properly. Did that fix it, history says I need to give it more time for a final verdict.

In the "Oh looky there" category...the low oil level light came on today. Stayed on for about 2-3 minutes then went out and did not return. Got the girl home and let her sit for 5 minutes on the level drive and checked the oil level...completely full. Not mid point, not almost full but to the "Full" line. My wife says she has had that happen once or twice before but it always had oil pressure (as it did this time) and never lasted more than a minute or so.

Looks like another trip to Mr. T's Parts department for a new sensor may be on the agenda.

I've heard of people having success just pulling that sensor and cleaning it up. Clean the contacts also and make sure the connector doesn't wiggle. Get a new gasket from your buddy at the dealership for the reinstall. Cheap and easy first, right?

 

[Traakon]

I've heard of people having success just pulling that sensor and cleaning it up. Clean the contacts also and make sure the connector doesn't wiggle. Get a new gasket from your buddy at the dealership for the reinstall. Cheap and easy first, right?

"Cheap and easy first, right?" LOL, seems I have been doing it wrong from the very start. I read some of the few threads on the OLS and the results seem to be mixed on if the cleaning resolves the problem. OSO is due for an oil change very soon so I guess I have until then to make the decision. I found the PN 89491-60010 for the sensor but will have to let the local guys find the PN for the gasket.

 

[Nay]

"Cheap and easy first, right?" LOL, seems I have been doing it wrong from the very start. I read some of the few threads on the OLS and the results seem to be mixed on if the cleaning resolves the problem. OSO is due for an oil change very soon so I guess I have until then to make the decision. I found the PN 89491-60010 for the sensor but will have to let the local guys find the PN for the gasket.

I'm chasing the same thing right now, except one morning when I fired her up it just wouldn't hold idle. No braking issues, no recovering as it dropped, just straight to dead once off the throttle, every time, 100% repeatable condition.

I replaced the PCV and VCV with grommets and hoses today, and that definitely needed to be done as some of the hoses and the grommets were brittle. But it didn't affect anything. So I have an IAC on order, which I got for $150 so not bad and hopefully that's the fix.

I'm too lazy to look at the FSM right now - what's the gasket for with the IAC since it's a plug in component?