I have been trying to solve my idle problem for some time now. Today i checked the fast idle operation and saw that the cam was off from the matching mark so i adjusted the screw and got it to within spec. This of corse after i had fully warmed up the car.
The next thing i did was check the BAC circuit by putting a jumper wire in the terminal as described and removing it with the car on to see if the rpms drop and nothing happened. In fact i realized today that i could simply leave my BAC connector off and it made no diffrence in the idle situation.

Before this morning my car had high idle with pulsing but it went away once the car got hot enough. Now after these checks my idle is constantly pulsing between 1300-1500 rpm and will not stop. I need some ideas on where to start with this guys.

Please HELP!!

 

Have you messed with the idle adjust screw yet?

If you're at 1500, the BAC has no need to work...

 

It sounds like the TPS is at idle (1K ohms) and throttle stop, or vac leak, or warm up cam, or bypass air bleed is pushing the RPM >1500; so the ECU give a fuel cut till it fall back down.

The trick (of course) is finding whats allowing more air.

 

Tell me you did not jumper a wire b/t the sockets on the plug of the bac. Naw, you wouldn't do that. Whew! For a moment I thought you blew the transistor in the ECU that drives the bac. Man, I gotta learn how to read better. I'm a functional illiterate, as you know.

EDIT: Did you pull the plug off your tps to see how that effects things? What happen when you did that?

EDIT: Like they said above....the bac makes up for shortcomings UNDER 750 rpm.....not over 750

 

Yeah thats what i thought the FSM said. It says connect a jumper wire to both sides of the initial set coupler, then directly next to this there is a picture of the BAC plug so i assumed that was the initial set coupler.
Welp so now what, Im fucked? I drove my car around today and dident really notice any diffrence.

 

How do i see if i fried my BAC circuit at the ECU

 

Well, since the BAC coil is what, 12 ohms maybe IIRC, jumpering it temporarily might not have fried your ECU, because the circuit would be designed for a heavy initial current draw (I would hope)...Now, back to the "why are you worried about the BAC when your idle is still at 1500" question...You have absolutely no vac leaks, right? And you haven't played with anything recently that has anything to do with idle speed, right?

 

Yes i played with the fast idle system cuz according to the FSM it said it was off, and ever since i adjusted that the pulsing has not gone away

 

I need to know if i in fact blew the BAC circuit at the ECU. How do i check it out.

 

BUMP

 

Did you jumper the yellow (at least on mine) plug next to the air box before messing with the idle settings? I messed with my idle settings once without doing jumping it and my idle went to ****. Then went through the entire procedure step by step, ie: tps setting, mixture screw, however it goes, and my idle was perfect. You need a DMM to do it right, well worth the 10-15$ cost.

Point being, just go back, make sure you do it exactly like the manual says and you should be fine as long as nothings fried. Maybe you missed a step or put it out of order, easy to do really. The FSM can be confusing sometimes.

EDIT: the pulsing you described was one of the problems that developes commonly from the idle cam and the mixture set not being coordinated, the computer thinks it's set one way, the two physical devices set two other ways. Everything's working it's own setting.