Stuttering fixed and idle still off

[CorsePerVita]

I replaced most all the seals for the intake runner.

I also replaced the fuel filter and routed the vacuum lines to a shorter distance (lobbed off some excess so the route wasn't super long).

The car now runs smoothly, feels like the power is back, behaves as it should and the stuttering of all things is now gone. I drove the car around for a while because the hesitation and stuttering would come back on and off as the car warmed up but this time there is none.

However... now that it runs smoothly, doesn't stutter, my next issue is that the idle is now about 100rpm higher than it should be. The high idle goes up about normally and drops down when the car warms up, so that seems normal. But the idle now sits at about 1100rpm and hunts up and down between 1150 and 1100. (but hey that's better than hunting between 1000 and 1500 like it was)

So I am not sure if I've still got some sort of vacuum leak, or if maybe the idle was messed with when the car wasn't running right and now it's off?

Would it be recommended that I set the idle again? Or is there perhaps something simple I'm missing?

[Scott R]

You fixed a lot of leaks from the looks of it, mixture is probably a tad off and the idle is a probably set a bit high.

[Bob Kontak]

Yes, reset the idle. Screw it in after it warms up - use a dime - the big air bypass screw.

You could have more air leaks but that is the nature of the beast till you identify them all.

Have you performed additional air (sucking) leak tests? Like spraying starting fluid (many say to use carb cleaner) on potential leak points while the engine is running? Engine will change rpm where it is sucking air.

I suggest plugging the blue hose to the distributor and the hose to the decel valve with a fat nail to eliminate those variables. The blue hose is the retard hose and I have had mine plugged for two years now. Starts way better now on first key turn. Not a purist method and masks some of the true issues but the car is 30 years old and these band-aid tricks can save you some heartache.

[CorsePerVita]

Originally Posted by Scott R

You fixed a lot of leaks from the looks of it, mixture is probably a tad off and the idle is a probably set a bit high.

Yeah I noticed after I replaced the seals it was good for like a day (the first side I replaced, did the other side today) and then days later it was being a pain again. Retorqued them back down and it's running right again, so I am guessing the seals needed to seat.

Originally Posted by Bob Kontak

Yes, reset the idle. Screw it in after it warms up - use a dime - the big air bypass screw.

You could have more air leaks but that is the nature of the beast till you identify them all.

Have you performed additional air (sucking) leak tests? Like spraying starting fluid (many say to use carb cleaner) on potential leak points while the engine is running? Engine will change rpm where it is sucking air.

I suggest plugging the blue hose to the distributor and the hose to the decel valve with a fat nail to eliminate those variables. The blue hose is the retard hose and I have had mine plugged for two years now. Starts way better now on first key turn. Not a purist method and masks some of the true issues but the car is 30 years old and these band-aid tricks can save you some heartache.

Thanks Bob! I will do that tomorrow. Thanks for the tip on doing it when it warms up. I figured that would probably be the way to go but wanted to make sure.

I haven't done any additional tests yet but that is a very good suggestion. I think tomorrow I'll give it a try and see if that sorts them all out. I'm glad to mostly have this car sorted at this point. It had several things when I bought it that needed done that are pretty much all done now. It's been a great car so far.

So you plug your retard hose? I think I read of someone else doing that somewhere. I lobbed off the excess vacuum (the vacuum line was VERY long and I wasn't sure why it was so darn long) so I routed it differently and lobbed off the excess and the car behaves well now.

[Bob Kontak]

The retard hose "delete' will help the car start better but it is masking imperfect operation of other parts or minor vacuum leaks. Not a crime to do this as long as you are ok with the hiding of the symptoms.

The vacuum hoses take a really long route. Trimming them back is ok as long as there is no interference (e.g., throttle linkage).

[CorsePerVita]

Alright...

I replaced about half the injector seals this morning. The stuttering and stepping feel I had is pretty much gone.

I drove it around till operating temperature was normal. Then let it cool off, started it again to see if I could reproduce the issue and it /seems/ gone. Idle on cold start is high, like 2k and very very slowly makes it's way down to idle. I would attribute that though to a sticky air valve since it does go back down eventually.

However, the rough idle seems fine. It feels much more smooth.

Upon pulling the 2 injectors closest to me at the back of the car, I noticed I could physically wiggle jiggle and move them around in the collars. Pulling them out was relatively EASY. After I took them out they were hard as freaking rocks.

I replaced them with new seals and the difference was obvious in fitment.

Power felt a lot more smooth, none of this weird sudden wake up stuff or hesitation type stuff.

Also, my idle did NOT hunt this time. It still barely pokes up in a range of about 50-100rpms, maybe... very small. But it is not the 500rpm hunt I was getting last time where it'd just jump from 1k to 1500 every second or so.

I had also planned on taking the distributor out and cleaning it per the really awesome tutorial we have on here. However, I was freezing my balls off outside so the progress I made tonight was fine by me.

Thank you for all your help!

[Bob Kontak]

Good job. 2000-ish RPM is not Abby Normal with a cold car on a cold day.

[CorsePerVita]

Originally Posted by Bob Kontak

Good job. 2000-ish RPM is not Abby Normal with a cold car on a cold day.

Ah ok good. That's reassuring. So mostly I just need to see if I can adjust the idle with the screw and see how it handles itself after that.

[CorsePerVita]

Idle screw brought her down. She had lots of adjustment left

[Bob Kontak]

You are ready to dig into the CO setting now as Scott R notes in the 2nd post. You can do it with a dwell meter and a 3mm wrench. There will be come crafting require for the 3mm wrench as your SC has metal fuel lines but it is a very rewarding process to get a leg up on the workings of the K-Jet with Lambda without springing for an exhaust analyzer.

It is simple once you have done it a few times so help is available if you are interested.

[CorsePerVita]

I think before I want to go that route I would like to clean out my distributor and make sure that's also operating as intended since I've read they tend to get sticky when dirty. From the crap I saw in the injector seals, I think I want to take a second look around the engine bay and just go through everything to ensure smooth operation, then go tackle down the settings

I greatly appreciate everyone's help though, thank you very much everyone. It's become a very happy 911.