Trouble Tuning idle without a bac valve
 

I am having trouble getting my idle right, my TPS is a small bit out of range 1k-6.5k, the car will idle at 1100 and I cant get it to idle any lower, I still have my thermowax. I believe it is running lean because its running really ruff and if I push on the AFM and make it think its getting more air it will run good. I messed with the wrong throttle adjustment screw I think (philips head one right near the elbow.) my throttle stop screw is just touching the throttle blade dealie but isnt making it open.

1. How do I adjust the variable resistor, its covered in glue.
2. How can I reset the philips head throttle adjustment if I wasnt ment to touch it.
3. Any other advice would be greatly appreciated, I appreciate your infinite wisdom.

it sounds to me like you have a vacuum leak.

With the variable resistor, just pick away at the glue/wax with a small screwdriver or??? til you see the screw slot. FYI..it only turns three quarters of a turn til it hits a stop. Don't force it past the stops.

Vacuum leak sounds about right or a misrouted vacuum hose. The bottom nipple on the rear of the throttle body. Where do you have it going? Where do you have the other three nipples on the back of the throttle body going?

The top hose on the front of the throttle body. Where is it going? And the two beneath it?

The ACV blockoff plate. Does it have a good gasket? The nipple off the maifold, just aft of the BAC, is it connected up? The air feed line to the BAC, beneath it, is it clamped at both ends?

Got a crack in the turbo inlet duct AT the turbo connection?

I do have a crack in the turbo inlet duct, BUT it doesnt go all the way through. I have the horizontal nipple on the LIM going to the brake booster, All my gaskets looked good, For the ones that didnt I used a healthy amount of super RTV silicone. The top nipple closest to the alternator goes to the Dual scroll solenoid. All the rest on that side are blocked off. On the firewall side I have caps on all of them except the top one, that goes to injector bleed. My FPR is fed from the diagonal one on the LIM tucked under the UIM one. My MAP and BOV are fed from the nipple pointing strait towards the passenger side strut tower. my split air pipe hole the one right above my coolant feed for the turbo is open, everyone seems to think thats fine. also theirs a larger nipple pointing strait up to the hood that is open because its doesnt seem to be connected to the manifold, just a small hole facing the firewall.

I might be a little wrong I am at work and just listed all that from memory. I will see if I can fab up a pressure tester or borrow one from work to test for vac leaks.

I should be looking for 13-14 psi of vac? anything less and I have a vacuum leak no?

First check for vacuum leaks. I use the pressure tester from www.boostpro.net/prodtester.html , but you can fab one for yourself easily enough. Then check the throttle and cruise control cables. There should be 1 - 3mm of free play, per the FSM specs. Most people just do it by eye but if you are really concerned about it, get one of those $15 digital dial calipers and measure the freeplay with that.

Otherwise, if the throttle stop screw is out of adjustment (too "tight", as in screwed in too far) it will idle too high. it's a screw with a nut on it on the back of the TB, you will need to have the intercooler off to see it. Take note that this screw usually doesn't need to be adjusted unless some previous owner already messed with it. It's set ok from the factory.

my car has no BAC but retains the thermowax, and I found that I had to have the stop screw set correctly for it to idle right. But that is on a heavily modded setup with a standalone, bigger primary injectors, etc.

you car should be pulling 15-18 inches of vacuum at an idle of ~750 or so. My car with a big streetport, pressure tested for vacuum leaks, made 15 inches at 850rpm (well +/- 50 b/c of the porting), but I specifically set it to idle higher due to a lack of a BAC. Keep in mind that stock ports (healthy motor) make more vacuum.

okay I am still having trouble, I can almost get it to idle okay then it starts surging, and dieing and catching and surging and dieing again. And depending on how I set the idle I can rev other times it just cuts out :( I am fucked.

Install a verified good TPS and pressure test for vacuum leaks, then get back to us. I don't understand why you are trying to get a car working with bad sensors.

I dont have a verified good TPS nor are their ANY local. My TPS will read a range from 1k-6.5k its not that terrible I dont think. I also dont have a pressure tester though a vac test showed 16 psi. I am thinking of borrowing a smoke machine and blocking off my air filter so I can "pressure test" I am having tons of shit from this thing :( I cant figure out how to set the idle right without emissions, I may have a vac leak though its not showing up from the old carb-clean test and I am loosing my god damn mind! I also need to go back to college in a week and the rx-7 is my only car :wallbash: lol and my college is about a thousand miles away :hahaha:

my main issue is I AM RUNNING OUT OF TIME :( 100$ to anyone in herndon who can get this thing drive-able for me