Idle rpm in gear too low

[Kinecty]

Hello there gang.
I've had an issue with my 86 2wd auto cargo van for some time now and it's about time that I sorted it.
Out of the blue my van started idling very low while in gear, so low that the engine was shaking and sputtering. Somewhere in the neighborhood of 300rpm. However the idle rpm in park is 850rpm. To remedy this so I could get to work reliably for the time being, I jacked the idle screw up to 1400rpm in park so it would idle at 850 in drive and kept driving my van for a few months. The problem with this fix was extremely hard shifting from park to drive and when cold and the engine is at high idle it's at about 2 grand in negative 30 weather. Yeah. I replaced the vacuum lines thinking I might have a had a vacuum leak and no change. I replaced my leaky intake boot and that actually made the problem worse slightly.
Basically my idle drops way too much when I put the van in gear, so unless it idles super high in park it will barely run while in gear or idle so low the alternator can't charge with only a few accesories on and the fan can't cool the engine adequately causing the engine temp to climb drastially while sitting at a stop light. If it idles in gear at 700rpm+ these aren't an issue.
I assumed there's gotta be an idle up solenoid for automatic transmission models which many newer cars incorporate but one of the Facebook guys insisted our vans don't have anything like this.
Anyone have any ideas? The service manual has zero information on diagnosing a high idle or idle issues related to gear selection.

[Burntboot]

Have you checked for stored codes?

[Kinecty]

Honestly no I haven't. I don't have a check engine light illuminated however I should check anyways I suppose. I know there's a grouping of connectors next to the airbox. Which connector am I looking for?

[Jdelgado]

https://www.toyotavantech.com/forum/content.php?196-Engine-Service-Connector

[Kinecty]

No codes unfortunately

[boogieman]

seems like a transmission issue to me...do you have any service history on it? im not an automatic transmission guy, but maybe time to drop the pan, replace filter, and see how much crud is in the pan if it hasnt been done lately...maybe someones put wrong oil or additives to help with slipping or something...

[Kinecty]

I have zero service history although it appears to have been serviced very well. Every time I go in to replace or refresh something I think after 270,000km would be worn out or in need of freshening up. Someone has already been in there and done it.
I change the transmission fluid regularly and it was clean when I got the van, no transmission issues so far.
I'm not sure where to look to be honest

[boogieman]

the factory service manual has a few tests you can perform that dont seem to involve special tools..it could be a simple cable adjustment...theres pdf manual on this site i believe, and also on fb..good luck, maybe someone with more auto experience will chime in..

[Burntboot]

When you start the vehicle and the instrument pack does its self check, does the check engine light come on then?
Maybe try inducing a code, just to make sure the management end of things is working.

[Kinecty]

Yeah everything is all good there. I tested it anyways unplugging stuff like you mentioned and I was able to code it out and then clear them

[Burntboot]

How long have you had it and how long has it been acting up?
Have you done any standard maintenance (plugs, filters..., compression test.....) since you've owned it?

[Kinecty]

I've owned the van for a few years, It's been doing this for about 3 months or so. I maintain the van meticulously, and it appears to me the last owner did as well. All the maintenance is up to date

[Burntboot]

Out of curiosity, how does it run outside of the idle issue, any stumbles or lack of power or bad mileage, noisy &/or smelly exhaust......

Assuming that tune up stuff is all up to date (especially the air filter), I think you need to start assessing the basic parameters.
I'd start with a compression test as well as checking static timing and just work thru the list from there.
As with most things in life, the devil is in the details.

In the "olden days" (like when you're van was built) we only used idle up solenoids when a load was induced, like when the AC was turned on.
Auto trans is just part of the crowd and no extra idle was required or supplied, and shouldn't be needed.

What part of the province are you in?

[Kinecty]

I'm in the GTA. The van runs amazing otherwise, lots of power and right on par with the rated fuel economy. I deal with low compression forklifts a lot at work and I really don't think that's the issue here. Although I really appreciate everyone's suggestions!

From what I've heard so far the only thing that makes sense is possibly a torque converter issue. Apart from that everything engine mechanical on my van is exactly the way it should be

[boogieman]

had another thought, not related to transmission, could it be something to do with a faulty brake booster? when putting into D or R im assuming youve got your foot on the brake. if you can try the parking brake or chocking the wheels and see if it has the same symptoms..i would think if the booster were leaking air it would idle up not down but maybe worth a try...the other thought was tps...im not sure it communicates with the idle air control like other cars, but maybe jump the connector to see if your at least getting the rpm drop...i guess some volvos used the same trans so maybe theres some more info over there...

[Kinecty]

Those are some great ideas!

[Kinecty]

I'll have to look into those more, might be exactly my issue

[Burntboot]

I know very little about the internal workings of an auto trans, but don't believe convertor failures are common, at least not on 80's technology.
I would have thought that if the torque convertor was locked up, it would have to be in neutral to start.
In Park, it would be cranking against the parking dog, no?
A failed booster would induce a vacuum leak and raise the idle, so not very likely.

Perhaps Tim will happen along and provide some guidance.

[boogieman]

true, but i did have an 85 that had a bad master..leaking out the pushrod shaft..the van had been neglected in other ways too, when i 1st went to check it out we got it fired up, but it died when the brakes were applied...this was with the pedal going to the floor, thought for sure the booster was done, but after the master replacement however everything was fine...i was prepared to just block of the manifold vacuum. ..maybe unrelated, but since we're grasping at straws..

[Kinecty]

If there's a small leak it would most likely cause I high idle. If it's a large leak it may induce the opposite

[Burntboot]

I've never known a vacuum leak that could cause a low idle.
Ahigh idle, sure, most of the time, but a big leak, that usually induces a stall.
I've never known a big leak to create a low idle, that feels like a stretch to me.

There is only one thing I have ever found to be at fault with a low idle and that is a cylinder running below its potential.
Under load and at speed it can ride open the coat tails of the others but at idle, that weak player will show his cards.

Fire it up, set the idle speed to spec in park/neutral (850?) then start pulling wires, one at a time and see if they all produce the same amount of work.
My money is that one of the cylinders is not pulling as hard as the rest.

Could be as simple as an oil leak into a spark plug well shorting out the plug or something as sinister as a burnt valve, but diagnosing the actual cause before pulling the trigger on the parts canon, is a much more satisfying method of reserve depletion.

All TV's are a negative influence on cash reserves, 4WD just cuts the commuting time in half!

[boogieman]

all that definitely makes some good sense...cant wait to find out the issue

[Jtbechtold]

So I was just having some similar issue and it was a spark plug that was fouled and gap was to large. The spark plug was showing a fat blue spark outside the cylinder but once installed if did not fire.

[MyToy]

Hmmm, same thing happened to be recently. After amost 70K after engine rebuild it started doing the same thing. Cold start perfect, idle down to 900rpm stick it in drive and the idle drops, engine shakes like a SOB then stalls. If I pick the idle up it is better but after up to operating temp if I am at a light and in gear it will slowly start going down in idle with a tiny bit of shake. Once I apply gas she runs fine. Checked all hoses, fuel lines, and check engine lights. Wasn't considering a spark plug problem. Was your problem ever solved?

My Toy

[Kinecty]

Honestly man I can't remember what it ended up being but I did get it sorted out. It ended up being something small but I don't remember what. Nothing crazy either.
I don't own the van anymore.

[timsrv]

I'm sure you checked the intake tube for cracks....right? This is the classic symptom for intake tube cracks. Try squeezing the tube during idle to see if the same thing happens. If it does, remove the intake tube and inspect around the ribs while squeezing/stretching. Tim

[MyToy]

Thanks guys. So Tim, when you say tube you mean the intake boot?

MT

[MyToy]

If it is the boot and is not salvageable is there any place I can get one?

MT

[timsrv]

The rubber tube that goes from the Air Flow Meter to the Throttle Body. I don't know if they are still available. Last one I bought new was ~ 15 years ago. Tim

[MyToy]

If it is the boot and is not salvageable is there any place I can get one?

MT


Checked the boot. It is ripped almost completly around the air intake side. Not sure if I can glue it.
A new one is best but I am not finding that anywhere.

MyToy

[timsrv]

I just checked too. It's Toyota part #17881-73020. Even megazip.com says "discontinued". Major bummer. Looks like used is your only option. There are guys who have repaired using silicone & tape, but to me that's pretty sketchy. I still use my van for a daily driver business vehicle, so this parts situation is getting serious. My wife and I have been talking about switching to a different vehicle for this very reason. Good luck with your search. Tim

[Gareth]

It's basically impossible to find a new OEM air intake hose. Supposedly "Dayco Air Intake Hose Toyota Tarago & Spacia YR22 2.2L 4Y 4YEC" (DAH122) works but you'll have to find a vendor in Australia that's willing to ship to the US. There used to be someone on eBay that would https://www.ebay.com/itm/222892268538, but there are no current eBay listings that ship to the US.

[timsrv]

I just sent an email to "Auto Parts Guys" in Australia asking if they'd ship to USA. I also asked if they would consider a bulk order of 10 or more. If they respond I'll let you know what they say.

[Jan-Willem]

The aussies have the toyota tarago 2.2, which I think has the same one, and it is available aftermarket. The trouble will be the shipping…
like the dayco dah122
https://www.ebay.com.au/itm/403596050790 (https://www.ebay.com.au/itm/403596050790?_skw=DAH122&epid=5054837177&itmmeta=01JA8MJWA6HX1P0CRMFSZSHHCM&hash=item5df8330166:g:1FgAAOSwv9JiU~4e&itmprp=enc%3AAQAJAAAA4HoV3kP08IDx%2BKZ9MfhVJKkM3z9 EAbBCnbM%2BJ4lHlklxdNf9UydFGMphmoGD9b0RLMV6mZjWw1G qBsDHazNGuCIq9D0pm%2FZ6dlLCeFGyDMxAmhVlOGj22wTJVG% 2FsZVppqV7wqQPs7NSyvDiOpiVcaA%2BuKy71pxy%2FqmyUqKZ dPy5%2B0K8rSeD9pOHZ57sfXNoUVo8skBgIZGtuGvuRgFrc045 Ib2rkD0PKJyRKpCwafFw6S5EWoKwDk1GdyiEie%2BG61e0D99% 2FAAD89mCPuMKvasyHX4HI2dS0aWRn1OSw0skV3%7Ctkp%3ABF BMksXLlNJk)
Or maybe https://www.ebay.com.au/itm/233350109700 (https://www.ebay.com.au/itm/233350109700?srsltid=AfmBOoqRXjxYWr7U9hxWhDDG7_-IAbHpwlgqZR57FmFnvYAu3XancrTQ)

[MyToy]

Well sounds like at least something. For I am in Tim if that works.

I think I am going to temporarily use a scat hose that I used on my airplane. These hoses are not rubber but more of a fabric. FAA approved for fire, spiral spring in side for strength and flexibility. The side port I can cut out and seal to attach the other hose to. And they last for ever.

I will get to the hangar and see if I have the right size. I have an assortment of them. Will keep you posted.

MT

[timsrv]

Thanks for the links. Unfortunately nobody offers shipping to USA, but I suspect somebody might if the order is big enough. I personally would want 3 or 4 of these. If anybody else is interested, please state how many and how firm your commitment is. The bigger the purchase the more likely they are to agree. Even if combined I expect shipping to be high (I'm guessing $30 or so each). Tim

PS: I'm hesitant to order in volume without 1st verifying these will fit our vans. Has anybody actually purchased and installed one of these? If so, what are your impressions?

[timsrv]

I just sent an email to "Auto Parts Guys" in Australia asking if they'd ship to USA. I also asked if they would consider a bulk order of 10 or more. If they respond I'll let you know what they say.

Auto Parts Guys responded saying the Dayco tubes are No Longer Available. Major bummer, by the time I found out about these they are all gone. Maybe I can talk one of the eBay guys to ship whatever they have left to me??? MT, please post a picture of what you come up with and report back with how it works.

[MyToy]

Hey Tim:
Wow, now that sucks.

OK, I will get over to the hangar and match one up. I will let you know how it works and send pics.

For sure it won't look like a factory product.:no: But who cares if it works.

MT

[MyToy]

Oh and by the way I am in for one for sure.

MT

[89van]

Yea, intake boot rips suck especially for cars, like our Vans, that don't have any available!! I have not inspected mine but I should considering my van has mostly? been running lean ever since I got it; that or a vacuum leak but I have not verified the correct idle speed too.

I should check that, and if it is torn, then yes I'd be down to order one of these intake boots for science! :silvervan:

[MyToy]

OK boys and girls, reporting in on my intake boot. After many hours the scat hose did not cut the mustard. It was fine except for the mechanical integrity of the bypass hose fitting that goes to the warm up regulator and a sensor. We tried reinforcing it with different types of material but the scat is so light and flexible it would not hold well.
So we ended up taking the boot, matching the rip to each side of the two pieces and using RTV. I was not very hopeful here but my buddy did the squeezing and I held it together. We just did enough to make it hold. Then, 24 hours later applied a second coat only this time it was a heavy amount getting the large hole left from the rip and the inside seam where to two pieces came together. It didn't even look so bad. But still the rubber is so old and brittle super care is advised putting this puppy back on. So I waited another 24 hours for it to really set up, and that it did. I then made ready for the install only this time I brought out to the van a tall pot of boiling water. I soaked the accordion portion in the water for about 5 minutes. It did wonders for its flexibility. I got it in without even swearing:dance2:

Hooked up the remaining hoses and crank her over. As expected, it raced at about 2K RPMs, which is where is should have been after cranking the idle up so high. Reset idle and she runs perfect.

Not an answer for the part but can surly get you back on the road.

I also ordered in a couple of boots used for 4 runners. Not sure if they are even close but I will send them back in not. But maybe we can find one, there are tons in use, that can be modified to work.

So all is good here. Thanks for all the support.:wave2:

[timsrv]

Glad to hear you got a temporary fix. I contacted all 3 of the Australian eBayers and all replied "we don't ship to USA". Even though I offered to buy all their product and pay actual shipping. Does anybody know why that is? Just seems odd as you would think they'd like to make the sale. Tim

[Gareth]

Probably because of returns/scams. It's too easy for buyers to make a "not as described" claim or other reason for return and then the seller is expected to foot the shipping bill for the return (as well as the original shipping AND hope they don't get an empty box returned).

Side note: I actually did return an empty box to a seller once because they never sent me the item and due to some eBay stupidity (order was bundled with another item I did receive), I had to do a return to get a refund instead of an "item not received" case.