YAIT - Yet another idle thread...

[FMC80]

Such weird behavior. Have you ruled out the VAFM? I’m not implying it has anything to do with your issues specifically, but I had idle issues on my 94 that were resolved with a refurbished VAFM. Mine was in range per the FSM but the spring tension was weak and was allowing the door to open and close when it shouldn’t have. It produced weak and stuttering idle and it would stutter in drive too. It would never be as systematically reproducible like yours though. Yours is a weird case my friend.

 

[mudgudgeon]

You could try a little more timing advance.
Use a paper clip to bridge the terminals in the diagnostic port, and increase timing to sonewhere in the 6⁰ to 10⁰ range.

Some 1fz-fe won't tolerate 10⁰, so be aware you may get pinging with 10⁰, and may have to settle for closer to 6⁰.

 

[gummycarbs]

replaced - All the small hoses. Cracked hoses, or hardened hose ends with a loose fit

Did you replace *all the hoses* or did you replace all the hoses that you deemed cracked, hardened, or loose?

 

[FMC80]

Did you replace *all the hoses* or did you replace all the hoses that you deemed cracked, hardened, or loose?

Gummy were you a Gunny in your previous life?

 

[CharlieS]

Did you replace *all the hoses* or did you replace all the hoses that you deemed cracked, hardened, or loose?

every single hose except the brake booster hose

 

[gummycarbs]

every single hose except the brake booster hose

Then why the second sentence?

And you mean every single hose except for all the ones you removed entirely while pulling out emissions equipment, right?

I deleted

• egr valve removed and temp probe bypassed with huddexpo jumper, home made block off plates new factory gaskets, removed egr pipe
• pair assembly
• all vsv related items, capping all unused ports
• intake manifold coolant lines, capped with silicone caps and clamps at head and water pump

Incidentally, I'm completely mystified by that last one. Also, wrapping the wiring harness with insulation *after* removing the EGR valve.

 

[CharlieS]

Then why the second sentence?

And you mean every single hose except for all the ones you removed entirely while pulling out emissions equipment, right?



Incidentally, I'm completely mystified by that last one. Also, wrapping the wiring harness with insulation *after* removing the EGR valve.

Correct

All hoses currently in the engine bay except the brake booster hose are new factory parts not brittle, and crack/leak free.

 

[CharlieS]

Such weird behavior. Have you ruled out the VAFM? I’m not implying it has anything to do with your issues specifically, but I had idle issues on my 94 that were resolved with a refurbished VAFM. Mine was in range per the FSM but the spring tension was weak and was allowing the door to open and close when it shouldn’t have. It produced weak and stuttering idle and it would stutter in drive too. It would never be as systematically reproducible like yours though. Yours is a weird case my friend.

I haven't tested this yet, but will do that. The connector is very firmly attached and I am concerned about damaging it. Is there a procedure to measure spring tension in the fsm?

 

[FMC80]

I haven't tested this yet, but will do that. The connector is very firmly attached and I am concerned about damaging it. Is there a procedure to measure spring tension in the fsm?

Okay, don’t mess with the connector two screws. The connector may have the rectangular shaped spring clip around it which you have to remove first to get the connector off.

I don’t remember reading anything about the spring tension in the FSM, but I spoke to the people who refurbished my VAFM about it and they tightened it up for me. They had to service mine a second time because according to them, although the parameters were within serviceable limits, the spring tension was was correct during operation. So they tweaked it and my cruiser runs like a dream now. The place I sent it to is called Bavarian Restorations, or BavRest.

 

[12bit]

Okay, don’t mess with the connector two screws. The connector may have the rectangular shaped spring clip around it which you have to remove first to get the connector off.

This is important advice. If you remove the screws, you have a 100% chance of destroying your AFM. Please don't ask me how I know this.

 

[OffRoadScott]

Having had idle issues similar I tested my AFM and it was good but still bought a known good one and am currently running it.

Check the O2 sensors, mine were causing a high CO/HC readings and the idle was affected by it too.

Also, check the wire harness near the EGR. Hopefully you do not have any shorts in the harness there.

I do not recall but under load while driving does it stumble or feel like you have a miss? Mine did and it was due to the wire harness. The sad thing about older model Land Cruiser the wire harness is no longer available.

 

[CharlieS]

You could try a little more timing advance.
Use a paper clip to bridge the terminals in the diagnostic port, and increase timing to sonewhere in the 6⁰ to 10⁰ range.

Some 1fz-fe won't tolerate 10⁰, so be aware you may get pinging with 10⁰, and may have to settle for closer to 6⁰.

I adjusted to 10 degrees and it is much happier. It is idling better, running better, has less hesitation and feels more peppy. Thank you.

 

[CharlieS]

Having had idle issues similar I tested my AFM and it was good but still bought a known good one and am currently running it.

Check the O2 sensors, mine were causing a high CO/HC readings and the idle was affected by it too.

Also, check the wire harness near the EGR. Hopefully you do not have any shorts in the harness there.

I do not recall but under load while driving does it stumble or feel like you have a miss? Mine did and it was due to the wire harness. The sad thing about older model Land Cruiser the wire harness is no longer available.

Fortunately, I don't have a stumble while driving, so that's good. It is only a symptom at idle.

 

[CharlieS]

I ordered the brake booster vacuum line, check valve grommet, a new dipstick seal, and an IAC oring, so we'll eliminate those as potential issues.

So far it likes that 10 degrees BTDC timing a lot!

Here's what we're working on:

 

[sbman]

Mine was having an erratic idle, rough that eventually graduated to an occasional misfire. It would idle low, sometimes die entirely, but did better/smoother at higher RPMs.

It was tired/old injectors. I replaced them (they had been cleaned/flowed previously) and it idles better than it ever has (I got it with 220K on the clock, it's at 340K now). Before replacing them, it would move up/down RPM as the A/C cycled on and off and when I put it from P-D it would change idle speeds significantly. All that is gone now and it idles rock solid at the proper RPM no matter if A/C is running or it is in P/D/R or not.

 

[CharlieS]

Mine was having an erratic idle, rough that eventually graduated to an occasional misfire. It would idle low, sometimes die entirely, but did better/smoother at higher RPMs.

It was tired/old injectors. I replaced them (they had been cleaned/flowed previously) and it idles better than it ever has (I got it with 220K on the clock, it's at 340K now). Before replacing them, it would move up/down RPM as the A/C cycled on and off and when I put it from P-D it would change idle speeds significantly. All that is gone now and it idles rock solid at the proper RPM no matter if A/C is running or it is in P/D/R or not.

May I ask what injectors you went with? I found this part number (23209-74080). This particular Toyota parts is pretty pricey! I can't see spending $1100 to $1500 on six fuel injectors though. I see a lot of aftermarket options, but am leery of using an unknown part or company. I'd love to know if there are any good aftermarket options.

 

[sbman]

May I ask what injectors you went with? I found this part number (23209-74080). This particular Toyota parts is pretty pricey! I can't see spending $1100 to $1500 on six fuel injectors though. I see a lot of aftermarket options, but am leery of using an unknown part or company. I'd love to know if there are any good aftermarket options.

Yeah, the OEM ones are expensive. I went with a set of 12 hole Denso injectors. After a whole lot of research on my part, the Denso injectors I selected are Denso Part Number 297500-0940. These flow 305cc and have 12 holes, are 14 ohms, and have an identical electrical connector. So the brand, the flow, the resistance and the connector are the same, but they flow through 12 holes instead of 2. They are 'short' style while the cruiser needs 'long' style so they need an adapter, it's a fairly specific adapter but they can be found. I know this won't be a popular idea, but I wanted to try it. If I have problems, I can always find some OEM injectors to put back, no modifications had to be made to install them with the proper adapters. I'm sure some new OEM would be great, but this is what I opted to do. If you want a source, I'll PM you but I don't have enough miles on them yet to call it 100% success. So far it runs better than it ever has. It has never idled great, even right after the rebuild and I had the injectors professionally cleaned and flowed during the rebuild, with the complete misfire starting about 100K after that.

 

[ZackR]

Before I messed with the injectors I'd run a few tankfuls of injector cleaner through, combined with some highway driving.

 

[sbman]

Before I messed with the injectors I'd run a few tankfuls of injector cleaner through, combined with some highway driving.

For me, one injector started failing entirely (#5) so that helped nail down the diagnosis. I had been through all the hoses, vacuum lines, all the same stuff described in this thread. I never messed with IAC though. As I said, it's not a popular decision to blame injectors, but for me it fixed all the idle issues.

 

[gummycarbs]

all the same stuff described in this thread

Your engine revved to 2,200 RPM at startup, with the AC off?