evoentertainment

So I just purchased my 7. The previously told me he took out all the emmision and added block off plates so it won't idle at 3 before warm up. But now the car starts at reall ylow idle, such as 700 or so. I would have to hold the gas down and rev it to 1500 or so and have it be fully warm or else it would just drop so low the car dies out. I was told a tune would fix that and have it idlin normal. Is that true? Or is there other things I would have to do? Thanks in advance!

mar3

iTrader: (8)

The car in question is a 1988 RX-7, so that takes it out of my sphere of knowledge. This question is really broad but let's see what the 2ndgen guru's have to say.

Mario III

evoentertainment

Yea I felt the question was kinda broad. Is there any additional info I can provide you guys with to help with the assestment? Thanks in advance!

Aaron Cake

iTrader: (1)

Don't you just love it when people hack up cars without any real knowledge?

Based on other botched emissions removals I have seen, they probably took out the cold start thermowax/cold start cam assembly and the BAC valve. If you put those two back in place the car will operate much better since it will now have the cold-high idle and the ECU will be able to regulate idle speed. Now adjust the TPS and make a good check for vacuum leaks.

evoentertainment

So what if I just get a tune. Cause I have a mgasquirt that I've meaning to tune. Would that take away the problem, have the ecu once again be able to regulate idle?

mar3

iTrader: (8)

You just got advice and you just ignored it..."So what if I just get a tune"..? LISTEN to what you're being told and start there! This guy knows his business and has seen a ton of cases just like yours. His best guess is worth more than simply tossing out a question again when you've been given a good place to start. A "tune" won't do a damn thing for you if he's right.

START THERE, then tell us what shape you're in.

RotaryRocket88

iTrader: (7)

Tuning is beside the point. Rotaries don't like to idle low when they're cold, which is why they had the cold start devices to begin with. Getting the thermowax and BAC back on will greatly improve idle, but in the meantime you can adjust the idle speed up above the 750 RPM spec to compensate some. The FSM will tell you the exact procedure for this.

evoentertainment

Putting those things back on, would have to put back on all of the emmision components? And would I have to take off the block off plates?

evoentertainment

What's FSM? Sorry as you can see I'm hella noob

RotaryRocket88

iTrader: (7)

The thermowax and BAC are not emissions related, but people love to take them off at the same time. Block off plates will likely be in place of both of these devices.

Factory Service Manual. There are links in the 2nd gen FAQ to download it. Look at the top of this forum.

evoentertainment

Thanks for all the answers and not being douche about my noob questions!

flipside27

sounds like the same thing happening to my car
let me know if their tips cure your problem! i just discovered that my thermowax-thingy has been removed as well

Aaron Cake

iTrader: (1)

If you are going to go with the Megasquirt, then that changes things. For one, you can use the BAC valve (put it back on and mod the 'Squirt to run it) to regulate the idle. This will allow you to set up a high cold idle just like the factory. TPS adjustment becomes largely irrelevant with a standalone, and any vacuum leaks are usually found at the time of install.

So yeah, in a roundabout way, a Megasquirt would fix this. Sort of like curing the disease by killing the patient.

evoentertainment

yea I was told that, but wanted some reassurance from you 2nd gen gurus before paying for a tune. thanks for being so helpful and patient with my questions guys!

evoentertainment

I was told if I wanted to have the car idling normally on cold starts, I can just set the coldstart anf enrichment on the MS and NOT have to put the BAC back on. Is that true?

And on side not; I would also have to plug in fuel pump lines and vacum lines prior to tune because the car is on stock ecu right now on MAF sensors and the MS is on MAP.

Aaron Cake

iTrader: (1)

No, not true. All ECUs have cold start enrichment. You need a little more air to idle up the engine to get a stable cold idle, which is why the BAC is needed. Without it, the engine will tend to idle lower and erratically until it gets some temperature. This is why almost every factory vehicle has a higher idle when cold.

evoentertainment

So with the tune, I would still have to put the BAC back on in order to rid the cold start idle issue?

Aaron Cake

iTrader: (1)

As I said:

evoentertainment

So what would happen if I were to put the BAC on now, without having my standalone tuned?

Aaron Cake

iTrader: (1)

Since the factory ECU expects to have the BAC, which is how it regulates the idle, your idle will improve considerably and cold starts may be a bit better.

evoentertainment

Well my regular idle (after warm up) is about 1300, and on cold start like I've said above would die out unless I hold the gas. so does this sound normal? Or well at least in my case. And is putting th BAC back on easy

evoentertainment

Ps aaron cake thanks for all your help!

evoentertainment

Also despite just getting the BAC back on and having my stand alone tuned, is there any other compoonents (any emmision components) I have to add back on in order for me to have a "normal" idle?