Thoughts? Rough start/low idle

[Beach Runner]

Hey guys,
My 96 SR5 has the 3.4L with 151K on the clock. When I first got it, it would idle around 1100 rpm's. I've since completed the ISR and deckplate mods as well as cleaned the TB and MAF sensor. After that it started and idled fine (700 rpm's), but within the last week (driving it a lot more, lost my company truck) it doesn't want to start until the 3rd or 4th try. When it does finally start, it now idles around 500 rpm's. I've doubled checked the vacuum hoses that were involved with the ISR mod, but they are all still snug and in place. Also, at the moment, I'm running with the deckplate closed because I've yet to add screen to the backside of the trim ring. And one more thing....I did remove the EFI fuse when while I was cleaning the TB/MAF and reinstalled it when I was through. Any ideas?

 

[Beach Runner]

C'mon, 63 views and not one idea???

 

[t4r4life]

i sounds like it's either fuel of spark, take one of your spark plugs out and check them, also low fuel pressure caused by a dirty fuel filter, take a cigar(cheap one)fire one up, unplug one of the vac hoses right behind the MAF blow into it see if there is any leaks

 

[zcruiser]

C'mon, 63 views and not one idea???

We prefer to read other people's opinions and then tell them why they're wrong.

If your EFI fuse was re-installed incorrectly, you wouldn't have jack. When's the last time you changed your plugs? Another member on here got the lucky job of getting his uncle's crappy-running 4Runner running right, and he replaced plugs, wires, cleaned the MAF and the throttle intake plate and now it runs like new.

{Edit: that was one of the worst run-on sentences I've ever written.}

So - How are your plugs and wires? '96 is pretty old for original stuff.

 

[Beach Runner]

Thanks t4r4life & zcruiser! Bear with me, this is the first forum I've ever joined
I got my T4R about 6 weeks ago and I just got laid-off so I haven't changed the plugs. I plan to do this as soon as possible. While I'm at it I'll go ahead and replace the wires too so I can establish a baseline. I'm not sure how old they are.
I'll have to look into cleaning the throttle intake plate. Any advise on how to do this? When I cleaned the TB I carefully tried to pull all the gunk out of it after I sprayed the cleaner. If some the gunk went further into the TB, could it have affected the intake plate?

 

[t4r4life]

now new people on the forums are gonna get a lot of @#% from old timers(lol i sound old) when they ask question that can easily be answered by using the forum searching function(i've done that), and always remember to understand everything before actually doing the task to avoid messing up stuff

 

[Beach Runner]

Gotcha. Ok, so I'm off to use the search function! If I still have questions, I'll be back. Thanks for the insight t4r4life!

 

[BrianSD_42]

about searching ....

TIP:
enter into google exactly like this >

site:toyota-4runner.org searchWord


BTW, to me your problem sounds exactly like the classic Idle Air Controller or AIC issue. Do a search for idle air control and see what pops up.

I have had the same issue for many years. It will not cause a CEL (typically) and it does not harm your engine. If it is the IAC then it should smooth out at about 800-1000RPMs.

My symptoms of AIC issue are: does not start without putting extra foot on the gas. problems go away after running it for a few minutes. very intermittent, could work fine for a week then have the issue again.

 

[Beach Runner]

Thanks Brian. I just got home from work and read your reply. My symptoms are exactly as you described. If I give it a little extra gas for a minute or so, the idle smoothes out. And today I've had no problems at all. One turn of the key and it started and idled with no problems. I guess I'll do some checking into the IAC issue. Thank you for the tip on searching as well!

I really appreciate everyone's help!! :thanks:

JB

 

[Trevloc]

We prefer to read other people's opinions and then tell them why they're wrong.

i thought docmt and jed were banned..... :lmao:

 

[Beach Runner]

Update:
Last weekend I did an oil and filter change, and replaced the pcv valve, spark plugs and plug wires. Since then, I have not had any issues with starting or idling. When I 1st start it, it idles around 1k rpm's and once warmed up, it settles in around 700 rpm's. I guess the new plugs and wires must have done the trick. Next up, transmission flush. Thanks again for all the tips!:thumb3:

 

[zcruiser]

:guitar3: