I bought an 87 4Runner with the 22re yesterday and noticed that when I first start the truck sometimes the truck idles rough almost to the point of cutting off. After you get on the road and give it a little gas, it runs just as smooth as any I have driven. Any idea of what I need to check on this thing first to fix this problem? Thanks for any help

 

Since you just bought this I would think the first thing would be a good tune up.

Once all the tune up parts are new it is easier to fine tune the trouble shooting if the tune up fails to fix the idle issue.

Could be the cold start injector circuit is not working correct.

 

I just read where someone else had the same issue, it doesn't do it unless the truck is run shut off and then restarted. They called it a warm start issue that is apparently common, now if I can just figure out how to fix it

 

When i went to leave for work it cranks fine, but it took it a while to catch. Unsure of what exactly is going on, dont want to dive into too much without having something to start with. I dont know, it wasnt doing it at all when I drove it or started it yesterday. Any ideas?

 

This is a picture of it actuallly in really good shape.

 

Ahh the infamous warm start issue (that's what I have named it lol)

Here read this. My post from a few month ago. Very good info in there.
https://www.yotatech.com/forums/f116...-issue-288051/

 

I actually read that whole thread earlier, but didnt see a permanent definite fix for the problem. Did you ever figure out what was causing it and get it fixed?

 

Not permanent fix. The toggle switch to the FPU works great. I use it everyday and love it. But it's definitely just a bandaid...

As also mentioned in that thread, there was a factory service bulletin for a new and improved switch that corrected the problem. But switch is no longer available.

As for now the only option a member named Grumpin came up with the toggle switch. We've still been trying to figure out more about the issue.

As of now I've got every thing on my truck operating correctly. Down to every switch, knob, and pulley lol. Everything but this. Very frustrating.

 

I just went out at work for a short break and tried to start it, its been sitting for 4 hours. Truck took 4 different cranks to get it started. Really hoping I didnt buy something thats gonna have hidden surprises everywhere. I dont even know where to start. The old carbuerated trucks I know but these EFI trucks I know nothing about.

 

Yeah that's a different issue. I don't have an "starting" problems. Fires right up every time, just idles really low on warm starts.

 

I dunno, may have bit off more than i feel like chewing on at the moment... hoping its not hg related or timing chain. I dont know, im going to talk to the guy tomorrow and see what he says. He works on them all the time. Maybe he will ahve an idea.

 

Well I guess at least i still have the 93 at the house. If i cant figure it out right away I have something else to drive.

 

is it on cold starts where there's extended cranking? Or hot? Both?

Personally from what you've explained, I don't think it's anything major. So don't go getting rid of it too quick, nice rig you got there!!

 

well i just went out again and tried something a little different on startup, and it started right up. Doesnt make sense to me, but i guess anything is possible, especially with a 28 yr old system. I did it almost like a glow plug on a diesel, turned the key on and let it sit for a few seconds before turning the key. It fired right up with no problem. Dont ask me... does that make sense to anybody or was it just a lucky start where the truck decided to do what it was supposed to?

 

Could be either just luck or the fuel system loses pressure when sitting .

see how it goes starting like that.

 

Don't rule out vacuum leaks. For the past two months I was chasing bugs like this. The tiniest vacuum leaks contributed significantly. Do a smoke test.

 

I thought a vacuum leak would have more affect once the truck was runnning and not as much during the initial startup. But im no mechanic just trying to learn. I will definitely start checking the vacuum lines.

 

So wyoming if the fuel system is indeed losing pressure, which is what it seems like it could be, what steps would i need to take to fix this issue?