AdmiralYoda

So after two long years of restoring the my 87 22RE 4Runner its finally on the road and is my daily driver. Over the past few days I've been finding all sorts of small problems that need attention.

One problem is that I have no fast idle at startup. I've set the timing per the FSM and adjusted my operating temp idle to 850RPM but I'm having an issue at startup.

Normally when you start an engine it idles at 1500 or so RPM and then gradually goes lower as the engine warms up. Mine isn't doing that.....at all.

It starts right up but the idle is real low, like 300-500RPM or so. A slight blip of the throttle and its at my set 850RPM idle. If I let the engine run on its own the idle will gradually get to 850RPM on its own over 10-15 seconds.

It doesn't matter what the engine temp is when I start it...it does this every time. What gives? The Idle Air Control Valve? I thought when those went bad the cold start idle was too high or there is surging?

Another cold start switch? Any ideas would be greatly appreciated! If it is the IAC I'm going to try and rebuild it as its one pricey item from the dealer.

Thanks!

osv

i think that '87 has the old idle air control valve system? rather than fix that dog, you'd be better of in the long run with the later model 22re intake system:

http://siestaoffroad.com/tbody.html

AdmiralYoda

That was on my list of things to do someday.....it may get pushed closer to the top of the list.

I'd like to narrow down the problem first and attempt to fix it without shelling out some $$$. If it is going to take some cash to fix it, and I have a dead IAC I'll probably just go with the late model plenum.

Does this sound like a bad IAC? I usually don't hear of a low idle until the throttle is pressed....

osv

http://www.autoshop101.com/forms/h60.pdf
http://board.marlincrawler.com/index.php?topic=36294

you can make the old throttle cable work on the intake swap, by using a die grinder to cut off the last 1/16" or so, and a barrel nut kit from pep boys... that's a trick you won't see anywhere else, everyone else swaps the cable as well... of course, if i break a throttle cable i got a problem, lol

AdmiralYoda

UPDATE!!! As I feared, the problem has gotten progressively worse as the past two days have gone by.

I just went outside to start the engine and make a quick errand and it was a PITA to get started. I had to feather the throttle just to get it to fire up and have enough RPM's to stay running.

Once it finally fired up it idled perfectly at 850RPM. It drove fine. We'll see what happens tomorrow AM when the engine is fully cooled down. It had only been sitting for a couple of hours when I just went outside.

Thanks for the link OSV....starting to think the IAC is definitely the culprit.

osv

there is also a cold start valve, located on the intake plenum, that injects fuel to help the initial startup.

make sure that it's plugged in.

AdmiralYoda

Is the cold start valve related to the cold start injector? I thought the cold start injector only fired when it was colder than 40 or 50 degrees? It hasn't been any colder than 75 for the past couple of days here....

AdmiralYoda

Okay so I checked the resistance of the cold start valve (aka cold injector timer) and it seems to be out of whack. According to the FSM the resistance should be 30-50 Ohms below 50F and 70-90 Ohms above 77F.

The engine had been off for about 3 hours and was still pretty warm to the touch. If I had to guess it would be 100-120F or so. The resistance was 53.3 Ohms. Obviously too low, which will make the cold start valve think the engine is colder than it really is.

The Cold Start Injector was 4.0 Ohms. Factory spec is 2-4 Ohms.

I didn't get to checking the IAC, which I believe is the real culprit. I'm at work and its a bit more to get at than what I can do during my lunch break. I'll take it out for inspection when I get home. I'll report back with resistance readings and pictures. I'll give it a good cleaning and see what I can do with it.

Will I need a new gasket when I take the IAC off or is re-usable?

osv

good question on the cold start injector, and how long it runs for... you could try unplugging the wire to it, and see if the symptoms change.

wyoming9

iTrader: (1)

First off it is a Auxiliary Air Valve not a IAC and they die of old age

I can`t recall if I ever had one that ever worked.

A Bi metal piece effected by the coolant temperature allows more air into the engine most all fail in the closed position every once in awhile you get a open one.

AdmiralYoda

Okay I'll start calling it the Auxiliary Air Valve.

I'll take it apart and clean it in the hopes that it will start working. What have I got to lose?

If its junk after I clean it I'll have to make the decision to buy a late model intake/TB or find a used Auxiliary Air Valve, as new ones are $200+. I actually couldn't find any intakes/TB on ebay at all surprisingly. There were 2 of each in my state according to car-part.com. Someone here will just say to go to my local pick n pull but these older toyotas didn't survive at all. They rot so bad all that would be left is the tires.

But cleaning this will have to wait until later today or tomorrow. I blew a fuel line on the way home from work yesterday and pumped 10 gallons all over the highway. The joys of discovering all the weak links after restoring a vehicle that has been sitting for 15 years....

osv

they all fall under the heading of iac, per the toyota autoshop document... more specifically, there are two different types of aav, is this the one with a wire connected to it? if so, i would try ringing out the electrical portion of it with an ohmmeter before tearing it apart.

looks like it's called iac when it's controlled by the computer, and aav when it's standalone, or held open 100% of the time via a 12v connection... so you could check for 12v, also continuity/resistance in the aav itself... there should be a procedure in the manual for this? also read page 4 of the autoshop document, it talks about idle speed changing when the hose is pinched, even after the engine is fully warmed up.

keep us posted!

AdmiralYoda

The AAV/IAC is going to take the back seat for a little while. The truck starts fine enough in this warm weather with a quick blip of the throttle at start up. I've got some other gremlins that need squashing before I conquer the AAV.

As I said above on Monday PM I blew a fuel line. I had it towed to my fathers shop (lucky me) on Tuesday and found that the return line blew out near the tank. It was spraying the fuel above the tank and it was running down on the frame rail which made it hard to find in my driveway.

Then on the way home I lost my brake pedal. I thought I blew out a rear brake line but I think my right front caliper is hanging up just slightly. The left front wheel wants to lock up when the brakes are pressed. It stinks like burning brakes too so I think its just overheating the caliper and fluid. I think the fluid was starting to boil giving me the squishy pedal. It didn't leak any fluid anywhere.

And then last night was the first real rain storm the 4Runner has been in since it was restored and I've got some leaks to deal with. The seal between the top and the cab must not be sealed well enough because water is running along the bed rail and pooling up in the rear quarter panels. On top of that there is a huge leak behind the fuse box causing pooling on the drivers floor.

Sorry....just ranting. But these are the things I can expect when driving a vehicle that hasn't hit the pavement in 15 years.

osv

if the brake hoses to the calipers are really old, they could look good, but be swelled up inside, which means that they clamp tight, but then don't unclamp quickly, because it's taking awhile for the residual pressure to bleed back up the brake line.

if it's been sitting for 15 years, you are probably looking at replacing all masters, all hoses, and all slaves... good opportunity to consider upgrading the brakes to the bigger front slaves, bigger mc, and bigger brake booster, since most of it has to be replaced anyway.

leaks... i had a bad one into the front passenger floorboard area, it turned out to be the seal around the antenna wire, where it went into the cab... had to pull the inside front fender skirt to see it, i think.

AdmiralYoda

I replaced the front/rear hoses, new caliper hard lines, new T100 V6 calipers/pads, used T100 dual diaphragm booster new T100 master cylinder, new stock 4Runner rear wheel cylinders, and new shoes. The rear hardware looked okay. Adjusters are adjusted and seem to be working properly. I also removed the LSPV and replaced it with a manual proportioning valve.

I think I've got a defective left front caliper that isn't releasing all the way and is overheating. If it makes a difference I also hear a click noise when I hit the brakes at low speeds. I only hear it on that caliper. I double checked and all the hardware is present and the caliper is tight. I just think I got a bad one. Its Raybestos which should be good thing....but a reman one.

As far as my leak goes...I have a sneaking suspicion its leaking through the cowl at the seam where it meets the cab over the fuse box.

wyoming9

iTrader: (1)

For what it is worth I ran my 22REC for years with the AAV disconnected and the coolant lines in a loop and a plug in the air line going to the manifold.

AdmiralYoda

Well after close inspection this weekend, the AAV was leaking coolant out of the body of the housing. I bypassed the coolant lines but left the air lines and electrical connector on for now.

The air line will need to be disconnected eventually, but since the AAV isn't working at all it isn't effecting my idle whatsoever. I'll fully bypass it and attempt to take apart the AAV and fix it. If that doesn't work it will be time for a early to late model intake swap.

Thanks!