Idle correction on stock ECU
 

So I utilized the factory procedure for setting the idle. The car has always ran at 1,500 rpm when warm since I bought it. I looked over the TB, vac hoses, sprayed and checked for leaks, etc. Possibly I may have the dreaded LIM/engine gasket leak. Anyway, so per the manual, I let the car warm up, made sure the fans were not on, factory temp gauge was where it should be.

* Car at operating temp

* Fans not on

*Jumpered TEN and GND using jumper wire

*Adjusted idle screw under throttle elbow. Disconnected TEN & GND jumper wire.

At this point the idle was at 1,000...Maybe high 900's. The idle screw is all the way in, it would not go in further. So my next step was the screw it instructs you to adjust on the side of the TB facing the front of the car if the idle is still off and the screw is adjusted all the way clockwise. I noticed the paint marks on the TB did not line up. So I loosened the nut, and adjusted it, it is already at the point where it was not touching the linkage. Essentially the only adjustment it would make is increasing the idle, the idle had been decreased by this method already as much as possible. So I secured the nut and called it a day.

The car idles warm at 1,000~ like I said now, which is still a bit off, and I have yet to find the culprit for what could be causing the idle to be off. If the screw with the nut was off its marking, I wouldn't rule out the possibility that maybe the other screws were "adjusted" as well, but the FSM does not cover anything else for warm idle adjustment.

Otherwise the car starts normally, the god awful AWS kicks in on cold starts (which I blip the throttle right away to disable), Idle hovers at 1,500, and slowly drops down to 1,000~. The car will bump the idle up for the headlights being on, etc, and it will settle down when those are turned off as well.

Just curious as to if anyone might have any ideas that I'm just not currently thinking of.

Have you checked the throttle plate bores to assure that these areas (both primary and secondary) do not have some carbon buildup that is keeping the plates from closing as far as they should? I had to clean mine to get them to close properly w/o binding when they tried to open due to this sort of buildup.

Link to related post (thanks, Dale): https://www.rx7club.com/3rd-generati.../#post12311153

My linked post there will give you a place to start. Most likely adjustments to the TB won't get you where you need to be, you have either a sizeable vacuum leak or the TB is stuck open.

Dale

Keep in mind with the old vacuum lines, although they may look like they're on there they might not be. A great example of this is the pcv hose on the filler neck. Although I'm sure it was rubber at one point, most have turned to plastic. If you tug on it, it slips right off. Its creating the illusion of a seal, when in reality it isnt. Cumulatively, over the 639 vacuum lines in the bay, this effect can create a difficult to find problem like what you have now.

Of course I could also be completely wrong and your issue could be elsewhere. It's for reasons like this I say non-seq is better. You cut down to a total of 5 (five) 「五」vacuum lines TOTAL. who doesn't want that?

I'll get on those suggestions tomorrow when its light out. I won't rule out the possibility of a vacc leak, I checked what I could, but it easily could be where I have not checked. Would a smoke test be worth it? Where would be the best place to introduce it?

Someone who wants an actual powerband and low-end torque :). 138,000 miles on my car and I've only had to replace one solenoid, works perfectly.

That said, the smoke test can be a tricky way to find a vacuum leak. Get a can of starting fluid and slowly spray where you think it may be - the engine will smooth out and rev up when it sucks in the starting fluid. It will only be between the throttle body and the engine. Unfortunately it could very well be a lower intake manifold gasket leak, that can happen if the car has the original paper gasket there.

Dale

mr.clark, " low end " is subjective. not having power below 3k is a minor trade off for the simplicity of a non-seq set up. man....... should i get the opportunity, i would love to do a hard core side by side to prove this fact. non-seq is better than seq in all aspects to include the most important one: MAINTENANCE.

The biggest concern I have is the vacc leak being on the LIM gasket and hosing that area with starting fluid...next to hot turbochargers I don't want to cause an engine fire, haha. Though starting fluid does evaporate quickly, It does make me nervous. I wouldn't be surprised if the car was on the original gasket =/.

it will only burn for a second :burn:

Check the operation of the thermowax/ fast idle cam. Is it stuck?

https://www.rx7club.com/3rd-generati...needed-841706/

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