High idle speed question (4 Viewers)

[Damcowboy]

Hey guys, my 97 80 series was idling at around 900 rpm, both in park and shifted into drive. After i fixed the cruise control it mostly now idles at 1,100 rpm in park, still at 900 rpm when shifted into gear. Once or twice it will still idle at 900. Also now when I start up it revs pretty high (1,700 rpm) a couple of times then settles down to 1,100. I’m not sure that hooking the cruise control cable back up to the throttle body is related. The throttle body is at rest in its fully clockwise position (when facing the rear of the engine standing at the front) when the accelerator is not pressed.

Its my understanding the idle cant be adjusted? I cleaned the MAF sensor already and the air filter is basically new. Any other suggestions/solutions?

 

[devo]

I’ve heard that this could be symptom of a bad heat sensor, the 2 wire one?

 

[Damcowboy]

I’ve heard that this could be symptom of a bad heat sensor, the 2 wire one?

Where is that located? Are you referring to the O2 sensor in the exhaust pipes?

 

[BILT4ME]

Hey guys, my 97 80 series was idling at around 900 rpm, both in park and shifted into drive. After i fixed the cruise control it mostly now idles at 1,100 rpm in park, still at 900 rpm when shifted into gear. Once or twice it will still idle at 900. Also now when I start up it revs pretty high (1,700 rpm) a couple of times then settles down to 1,100. I’m not sure that hooking the cruise control cable back up to the throttle body is related. The throttle body is at rest in its fully counter clockwise position when the accelerator is not pressed.

Its my understanding the idle cant be adjusted? I cleaned the MAF sensor already and the air filter is basically new. Any other suggestions/solutions?

Get a new throttle cable and properly adjust it. If yours is missing most of the rubber sheathing on the outside, then you need a new one. This is not uncommon on these.

 

[Damcowboy]

Get a new throttle cable and properly adjust it. If yours is missing most of the rubber sheathing on the outside, then you need a new one. This is not uncommon on these.

I thought of that. If the throttle is fully rotated clockwise (when facing the rear of the engine from the front, i said counter clockwise originally, that was backwards) in the at rest position wouldn't that preclude the throttle cable being the issue? I’ll probably replace it anyway, but all three cables, the cruise control, the throttle kick off and accelerator cable all have a tiny bit of slack in them when the throttle is in the idle (at rest) position.

 

[BILT4ME]

I thought of that. If the throttle is fully rotated clockwise (when facing the rear of the engine from the front, i said counter clockwise originally, that was backwards) in the at rest position wouldn't that preclude the throttle cable being the issue? I’ll probably replace it anyway, but all three cables, the cruise control, the throttle kick off and accelerator cable all have a tiny bit of slack in them when the throttle is in the idle (at rest) position.

Typically the throttle cable is the culprit.

I thought the same thing, had similar issues, swapped it out, problems went away.

I think the trans kick-down cable is NLA.
They all need to be properly adjusted.

 

[Damcowboy]

Typically the throttle cable is the culprit.

I thought the same thing, had similar issues, swapped it out, problems went away.

I think the trans kick-down cable is NLA.
They all need to be properly adjusted.

Being a new 80 series owner I am surprised how many NLA parts there are. I thought my 96 Bronco was bad, but the aftermarket parts for that is waaaay better then the 80.

 

[jonheld]

You can't adjust idle speed. It is set by the ECU which pushes the ISC valve. As stated already, the most common culprit is the throttle cable. However, if you think that the throttle plate is against the idle end stop then it could be a misadjusted ISC. Proper idle speed is 650 at normal operating temp.

 

[BILT4ME]

Being a new 80 series owner I am surprised how many NLA parts there are. I thought my 96 Bronco was bad, but the aftermarket parts for that is waaaay better then the 80.

Are you being told this by your local dealer?

If so, they are pulling the wool over your eyes. These were built in other countries until 2007 (the 80 series) so depending on which version you have, there are tons of parts available. I'm pretty sure your 1996 Bronco has more discontinued parts than a LC because US automakers are only required to make parts for domestic vehicles for 10 years. Now aftermarket, maybe so, but that's not OEM.

Toyota dealerships are NOT equal. They make up their own MSRP and discount levels and some just decide they don't want to supply some parts. There are a few online places to buy parts here that are very responsive.

Toyota Online Parts | Genuine Toyota Parts | Toyota Parts Online - https://toyotaparts.ourismantoyotaofrichmond.com/?referrer=toyotaparts.mcgeorgetoyota.com (not 100% sure about these guys now....they just changed ownership)

Toyota Genuine Parts - Olathe Toyota

At Olathe Toyota we stock Toyota Genuine Parts designed specifically for your vehicle. Whether you are looking for wiper blades for your Toyota, cabin air filters for a Camry or timing belts for older Toyota vehicles, our team of trained Toyota parts experts are ready to help you find the right...

www.olathetoyota.com

www.partsouq.com

I usually use partsouq to plug in my VIN, search the part number, then either buy from them or shop it with other dealerships.

 

[Damcowboy]

You can't adjust idle speed. It is set by the ECU which pushes the ISC valve. As stated already, the most common culprit is the throttle cable. However, if you think that the throttle plate is against the idle end stop then it could be a misadjusted ISC. Proper idle speed is 650 at normal operating temp.

Is adjusting the ISC something I can do or does Toyota have to do that?

I disconnected the throttle cable entirely from the throttle body and it made no difference to my idle rpm’s

 

[jonheld]

Is adjusting the ISC something I can do or does Toyota have to do that?

I disconnected the throttle cable entirely from the throttle body and it made no difference to my idle rpm’s

Download the Toyota factory service manual (FSM) from the resources section. Everything you need is there.

 

[Damcowboy]

Ok, an update. I was literally driving to the local Toyota dealership to see if they had any ideas, and the first stop light I hit my idle was down to 630ish rpm. Never seen that in the month and ~1,000 miles I have had the FZJ80. I shut off the engine, restarted it, no surging, no high rpm, and it settled down to 630 rpm immediately.

Huh!

The only things I did was clean the MAF sensor with MAF sensor spray and the electrical connection with electrical connection cleaner spray, add some dielectric grease and plug it back in. The other thing I did was to add a can of high mileage sea foam to my fuel tank, cause that worked to sort out an idle issue on my 96 Bronco.

I have driven about 20 miles since I did those things.

I dont know which “thing” I did fixed the issue, one or all three or some other combination but as for me I am a firm believer in Sea Foam. Some may think its snake oil but its been a part of fixing idle issues in a 96 Ford and now a 97 Toyota. So every 2,000 miles or so I am putting a can of that stuff in both trucks.

 

[BILT4ME]

Ok, an update. I was literally driving to the local Toyota dealership to see if they had any ideas, and the first stop light I hit my idle was down to 630ish rpm. Never seen that in the month and ~1,000 miles I have had the FZJ80. I shut off the engine, restarted it, no surging, no high rpm, and it settled down to 630 rpm immediately.

Huh!

The only things I did was clean the MAF sensor with MAF sensor spray and the electrical connection with electrical connection cleaner spray, add some dielectric grease and plug it back in. The other thing I did was to add a can of high mileage sea foam to my fuel tank, cause that worked to sort out an idle issue on my 96 Bronco.

I have driven about 20 miles since I did those things.

I dont know which “thing” I did fixed the issue, one or all three or some other combination but as for me I am a firm believer in Sea Foam. Some may think its snake oil but its been a part of fixing idle issues in a 96 Ford and now a 97 Toyota. So every 2,000 miles or so I am putting a can of that stuff in both trucks.

I see how you are.....

 

[Damcowboy]

I see how you are.....

I hope thats a good thing!

All I can say is I leave for a 3,000 mile road trip to Canada in 3 days for the deer hunt and I have been working like a crazy person trying to get the 80 ready (replace leaking rear main seal, remove the seized viscous coupler, replace broken switch on transfer case, replace leaking seals, new bearings and races in the rear axles, new track bar ends, new u joint in rear drive shaft, new radio receiver and back up camera, cup holders, arm rest ….), and the idle issue went away with 20 bucks of spray and cleaner.

I’ll take the win.

 

[BILT4ME]

I hope thats a good thing!

All I can say is I leave for a 3,000 mile road trip to Canada in 3 days for the deer hunt and I have been working like a crazy person trying to get the 80 ready (remove the seized viscous coupler, replace broken switch on transfer case, replace leaking seals, new bearings and races in the rear axles, new track bar ends, new u joint in rear drive shaft, new radio receiver and back up camera, cup holders, arm rest ….), and the idle issue went away with 20 bucks of spray and cleaner.

I’ll take the win.

Maybe post your route so we can all keep track of you........


Seafoam is evil. But its yours. Do what you want to do.

 

[Malleus]

Ok, an update. I was literally driving to the local Toyota dealership to see if they had any ideas, and the first stop light I hit my idle was down to 630ish rpm. Never seen that in the month and ~1,000 miles I have had the FZJ80. I shut off the engine, restarted it, no surging, no high rpm, and it settled down to 630 rpm immediately.

Huh!

The only things I did was clean the MAF sensor with MAF sensor spray and the electrical connection with electrical connection cleaner spray, add some dielectric grease and plug it back in. The other thing I did was to add a can of high mileage sea foam to my fuel tank, cause that worked to sort out an idle issue on my 96 Bronco.

I have driven about 20 miles since I did those things.

I dont know which “thing” I did fixed the issue, one or all three or some other combination but as for me I am a firm believer in Sea Foam. Some may think its snake oil but its been a part of fixing idle issues in a 96 Ford and now a 97 Toyota. So every 2,000 miles or so I am putting a can of that stuff in both trucks.View attachment 3474663

I'd bet your IAC was stuck.

 

[Damcowboy]

I'd bet your IAC was stuck.

What is an IAC?

 

[jonheld]

What is an IAC?

Idle air control valve. It's what the ECU uses to adjust idle speed.

 

[Damcowboy]

Idle air control valve. It's what the ECU uses to adjust idle speed.

Update:

OK, the high idle issue did not, in fact, go away with Seafoam. It did for a while but came back after about 400 miles. So I followed jonheld's advice and looked into the IAC valve. I didn't know where it was but it wasn't hard to find, it is facing the front of the engine attached to the throttle body opposite where the accelerator, cruise control and throttle cutoff cables are (on top of the engine). See the picture below, its the black circular object in the middle of the picture.

I replaced the IAC (part 22270-66011), along with a new O ring (part 90079-60004, the new IAC valve normally does not have a new O ring) and that solved the problem for good.

Of note, there are 2 Philips head screws that hold the IAC onto the throttle body and mine where locked in place. I got the top one out but the bottom one is in an awkward spot and you cant get a tool straight in on it so its really easy to strip the screw if you are not careful, like using a drill to try to twist it out (ask me how I know). If you have a cordless driver or some such use that and be very careful in trying to remove it. I eventually got mine out with an easy out and driver but it took a while, I had to buy some tools I didn't have, and I was very close to having to disconnect the entire throttle body off the engine to be able to get at the stripped screw on the IAC. You can see in the zoomed picture I replaced the screw with a machine bolt so its less likely to strip if I ever need to remove it again (the thread is #10-32 x 5/8"). A dab of anti seize was also applied.

 

[jonheld]

the thread is #10-32 x 5/8").

What is the possibility of Toyota using an SAE thread considering that every single other fastener is metric?