Does this model year have a test port that needs to be jumped to set the idle and timing?

 

My FSM says nothing about it, but I did read in another thread from almost a decade ago that it should be done. Once the rain clears up I'm going to give it a try.

 

Timing belt marks pic.

Maintenance & Repair Questions - my 1985 toyota camry died when i pulled into a gas station. it turns o... - CarGurus

my 1985 toyota camry died when i pulled into a gas station. it turns over, its not the fuel pump or plugs, but its not getting a sprk. What could it be??? ...

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idle adjust no mention of test mode jumper.

idle speed 1985 toyota camry - Toyota Car And Trucks Forums

 

Ok it looks like the 1985 Camry has the same diag connector as the 1988 thru 1991 Camry. Thus jump pins te1 to e1 then adjust distrib timing and idle speed until both meet spec.

 

I'll give it a shot when I'm available. I've poured over my FSM and Chiltons and can't find any mention of needing to jump the diag connector but I'll try it out. I won't be able to bring the RPM's down but I should(?) be able to see if there's a difference in the timing with the connectors jumped.

I want to save the idle screw adjustment as a last-resort option as my issue could easily lie elsewhere. Still need to rip out the IACV and whatnot.

 

On the gen2 Camry, you can adjust the timing if the engine speed is up near 1k rpm. I just don't know if the gen1 only uses vacuum advance or if it has the ESA (electronic spark advance) system. If it has electric advance, you'll need to use the jumper. If not, just pulling vacuum should work.

Looking at the pics, the distributor is pretty far from the middle, so I would guess your timing is not correct.

-Charlie

 

It has a mechanical and a vacuum advance. The ignition timing is definitely off but it still start's and runs fine, I actually drove it for a very long time with this timing without any problems. It's not the issue of actually setting the ignition timing itself but getting my idle low enough to set/check it. 950rpm is the max per the FSM. I'm going to look into the CA/US timing marks and make sure I have it on the right one. It could be on either one, easily overlooked in my rush to do my timing belt, luckily not that big of a problem to fix.

 

Timing and idle adjustment are tightly coupled and not independemt. Thus set timing first then the idle then the timing and then the idle again etc. once no adjustment of either one is needed then everything should be good to go.

 

Will be doing this after I confirm my timing marks on my cam pulley are in the correct spot.

On a brighter note I took it in for an alignment. It feels so good to get it back on the road again, with a straight steering wheel nontheless!

Thanks for everyone's help.

 

Don’t confuse the idle adjust screw with the idle stop screw. The factory sets the idle stop and people play with it anyways. The adjust screw is meant to be adjusted after tuneups and tbelt changes. Later cars now use a maf thus no idle adjustment is available.

 

Do you have a picture of it? I know what I'm going to be turning is the idle speed adjust screw but have never heard of an idle stop screw.

 

Apparently your model year doesn’t have an iac.

1985 Toyota Camry 1985 2.0L Gas Engine Camry Will Not Idle

Hi, after I changed my plugs, oil filter, oil and air filter, I started my car to back it off the stands to find that it would not idle, it was not ...

www.2carpros.com

 

Also your car might have carb thus no idle stop but some people call idle set or maybe mixture screw.

https://califcarb.com/carb-rebuilding/how-to-adjust-your-carburetor-at-idle/

 

It's fuel injected and it does has an IAC of sorts, in the FSM it's called an "Air valve" but it's purpose is to control the amount of air going in according to the temperature, increasing or decreasing idle. It's a silly little thing but I know it's on the car. I read an old thread about how to free them up if they get stuck. It's not an IAC in and of itself but it's close enough I think it fits the definition.

 

Since I don’t have any info on your car other than confusing info I’ve found from others on google vs what you have it’s difficult to advise.
I’d think since you have fuel injection then an idle stop should be there.
I guess a close up clear pic of throttle with cables and screws would be better than a vague diag from various 1985 Toyota’s on google.

 

Since I don’t have any info on your car other than confusing info I’ve found from others on google vs what you have it’s difficult advise.
I’d think since you have fuel injection then an idle stop should be there.
I guess a close up clear pic of throttle with cables and screws would be better than a vague diag from various 1985 Toyota’s on google.

Yeah there's not alot of information about these cars anywhere. I know quite alot about them but not everything so I just go off of the FSM for the most part. I have this picture for now. Where you see the two hose clamps doubled up on TB is right above the port for the idle adjust screw. The third pylon from the right.

 

When looking at the TB pulley I can’t see the idle stop screw which controls how much the throttle plate closes. So do you see anything that will prevent the TB plate from completely closing when car is idling? The idle speed/mixture screw adjust that you have just controls the air bypass around the TB plate when TB plate mostly closed at idle. Similar to 92 corolla timeframe.

 

Correct, there is no idle stop screw. The throttle plate closes fully, and the throttle cable has the specified amount of slack. I've been wondering about the TPS, I need to take it off and bench test it. There's only a few things that can affect my idle speed other than the idle screw and the TPS is one of them. I have faith in my 36 year old Nippon Denso electronics, but I do need to bench test it and the IACV as well as check it's operation. I also need to get a reliable tachometer preferably in a cluster so I don't have to fiddle with the inductive clamp on my timing light, although im sure it works fine.

 

From poking around I find that the Air Valve is highly suspect. It draws air before the throttle plate and dumps it in the surge tank (maybe wrong terminology). I'm gonna have to rip it out and test it for sure.

 

I got the air valve out and it sure was stuck and caked up with carbon. Freed it up with a couple drops of ATF and some krud kutter, time to check it's resistance now. Should be 40-60 ohms with the valve closed for anyone who needs to know. I got 49-50 so I'm excited to see what difference this will make.

 

You can also use foamy engine bright with a q-tip or old toothbrush to clean AC valve and throttle body plate.

 

Turns out my "Air valve" isn't operating properly but since it sits in the "closed" (warm) position I went ahead and set the idle lower using the screw with the engine warm. Now I just have to see if the timing light will play nicely with it.

 

Even after cleaning it’s closed? How can you tell? Some people test by dropping it in a pot of hot water on the stove and checking the flow but I don’t think these totally close when hot. Then in the freezer to open it back up.

 

I popped the upper hose off the next day early in the morning while it was still very cold and saw it was still closed from when I had brought it inside and warmed it up the day before. It also didn't have it's specified gap at room temperature while I was cleaning it, nor could I get it to its spec with it's adjustment screw. I put it back in the car anyways because that's where it belongs lol. It's not too big of an issue as it's primary function is a choke and controls high-idle for cold starts. I don't mind holding the throttle down for a little bit if I have to. It's a funny little gizmo, I already sourced one on eBay that I'm going to throw some money at and see what happens.

 

Sounds like it is basically a wax thermostat for air. Interesting. No electrical connections?

-Charlie

 

There is a 2 pin connector on it with a resistance specification for when the plate is closed (warm). I'm not entirely sure what role it plays exactly as the ECU gets it's ambient temperature reading from the AFM. I'll have to dig in the FSM a little more.

 

Years ago I bought a new AC valve and cut it apart to see how it worked. It’s not a thermal couple but acted like one. When the valve was removed from the cut apart housing and placed in a hot pot of water the wax or material inside would push the pin out and when cooled in fridge it would recede. The pin pushed a flexible plate out to close the passage way and when pin receded, the flex plate would return back opening the passage way and help push the pin back in.

Modern AC valves are electrical and with no voltage or ground have a preset opening ,and when a voltage is applied, the valve swings open. I don’t think there is an in between gap that varies as temp increases from cold to normal operating temp. This is why there is a throttle pot that is vacuum controlled that controls fast idle on some cars. I.e. 1992 corolla. More modern ones rely on MAF to function the same way.

 

I did some poking around the electrical diagrams and found where this "Air Valve" comes into play. In the diagram it's identified as a coil? Then going into a switch for the "circuit opening relay". Sparing the lengthy dialogue I see that it does get intercepted by the ECU at one point, and the EFI fuse at the other, also running into the AFM.


Just curious to see what everyone thinks about this? To me it almost seems redundant, obviously the car doesn't need a functioning unit to run. But on the other hand it seems there's a possibility that the ECU takes some sort of information from it? The FSM is very vague and Chilton's got nothing. It doesn't show up in their diagrams.

Sorry the picture is upside down!

 

It isn't connected to the ECU at all. It is just constantly powered when the vehicle is on (well, when in the STA key position or the AFM flap is opened - the same as the fuel pump). Looks like it is not a solenoid coil but a heater coil.

So, it likely stays open when cold and the heater coil heats up around the same speed as the engine combustion chambers, lowering the idle as the engine can handle the lower airflow amount.

-Charlie

 

It isn't connected to the ECU at all. It is just constantly powered when the vehicle is on (well, when in the STA key position or the AFM flap is opened - the same as the fuel pump). Looks like it is not a solenoid coil but a heater coil.

So, it likely stays open when cold and the heater coil heats up around the same speed as the engine combustion chambers, lowering the idle as the engine can handle the lower airflow amount.

-Charlie

I haven't experienced any startability issues thankfully. The car just starts and begins to idle at it's regular hot idle speed. I've just been giving it a little bit of gas for the first minute of running so it can emulate some sort of a coldstart high-idle.

Thanks for the explanation. That makes alot more sense now that it's been bisected a little bit more. Still a funny little part to me. 22RE's have a very similar situation but theirs is vacuum instead of electrical (however that works.)

 

This is a pretty simple valve operationally.

The bimetal is the thermocouple part of the valve and when heated by the coil (probably tungsten wire and the resistance measured limits the amount of current pulled thru it) due to the battery being connected, the bimetal flexes. The spring on the gate valve puts constant tension on the gate valve but is being stopped by the bimetal not flexing so that the gate valve can move which closes the valve. The vacuum from the Throttle body is bled to the atmosphere based on a predetermined hole size that was calibrated to be 100 rpm change - like a vacuum leak - which cases the rpms to be higher and when warmed up, the gate valve is closed stopping the vacuum leak and thus lowering the rpms.

So the pics in the FSM shown don't mention to check for a vacuum or forced air on the other side of the valve once cooled down by applying a vacuum pump to the opposite side, or forced air, and when hot, no vacuum or forced air is felt. To check the valve while on the car, you can use your finger to sense a vacuum/no vacuum while the car running when cold or after warmup.

 

That was a perfect explanation. I knew it was simple but couldn't wrap my head around it. Thanks alot!

 

If a recall, there is a coiled version of a thermocouple on the 1995 camry to control the rpm during warmup. The coiled version is held rigid at one end and as it heats/expands the spring action tightens or loosening with the other end pulling a i.e. a lever. It looks like a flat metal bar looped in a spiral shape where the surfaces of the coiled metal bar don't touch so that it can expand/contract due to spring action. The one on the camry could be adjusted a little to control the high/low idle points by slightly rotating the coil. The one on a friends daughters camry had to be replaced since any adjustment done wasn't enough.

BTW, thermocouples can wear out since after so many on/off (hot/cold) temperature cycles the bimetal will loose its springyness causing the high or low idle to be out of calibration. In your case the heated part may not move far enough to completely close the gated valve. The other way that they wear out is the resistance of the coil wire is such that the bimetal can't get hot enough or is to hot.

 

I got the new part in the mail and it works as it should. I did notice a crack in one of the tubes so that will need replacing eventually but is effectively bandaged with a zip tie

 

Just to add on, I’ve found that my valve seals are leaking a bit. I think the PO turned the idle up to rid of the blue smoke after idling for awhile. This is fine and dandy with highway driving but makes for a drastic and severe drop in city MPG.

Ive found a remanufactured head for a pretty penny which I will gladly dump out my wallet for. So my next update will be probably be that project. My decision to replace it is based on the overall mileage of the engine. I might play around with the old head and try some porting and polishing.