Idle and other miscellaneous potpourri
08-28-01, 06:55 PM
#1
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Idle and other miscellaneous potpourri
1990 GXL.
I adjusted the TPS today using an voltemeter and the wires trick, where you get two of them to read ~1 ohm and the other two the same at WOT. However I could not get the two to match; I had to settle on about .85 for the closed and .76 for the open.
The idle is alot better now but not perfect. with the lights on it idles great; I turn them off and it starts to fluctuate 700-800. A/C seems to be smoother too. Overall the car runs much better now but, but I'd like to get the last few kinks ironed out.
On to the BAC...I haven't studied up on this much, I know what it's supposed to do, but I wonder just how the two are related (TPS and BAC).
Where is the BAC adjustment screw? Where is the idle adjustment screw thats supposed to be down by the pass. strut tower? And also, how do I go about adjusting the mixture screw on top of the intake? So far I've left that alone.
One more nag, the auto seatbelt on the drivers side won't fully open. It gets about 4 inches from the stop, then I have to take the tension off the belt for it to go the rest of the way.
Changed the fuel filter finally, made a big difference. But I dropped the old one on my fender and put two small dents there.
so thats my update. any links to pictures of the BAC or idle screw, or just any help at all thanks.
Joe
I adjusted the TPS today using an voltemeter and the wires trick, where you get two of them to read ~1 ohm and the other two the same at WOT. However I could not get the two to match; I had to settle on about .85 for the closed and .76 for the open.
The idle is alot better now but not perfect. with the lights on it idles great; I turn them off and it starts to fluctuate 700-800. A/C seems to be smoother too. Overall the car runs much better now but, but I'd like to get the last few kinks ironed out.
On to the BAC...I haven't studied up on this much, I know what it's supposed to do, but I wonder just how the two are related (TPS and BAC).
Where is the BAC adjustment screw? Where is the idle adjustment screw thats supposed to be down by the pass. strut tower? And also, how do I go about adjusting the mixture screw on top of the intake? So far I've left that alone.
One more nag, the auto seatbelt on the drivers side won't fully open. It gets about 4 inches from the stop, then I have to take the tension off the belt for it to go the rest of the way.
Changed the fuel filter finally, made a big difference. But I dropped the old one on my fender and put two small dents there.
so thats my update. any links to pictures of the BAC or idle screw, or just any help at all thanks.
Joe
08-28-01, 07:07 PM
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Joe,
I thought we showed you the BAC valve on Sunday??? It is a 4 inch cylinder shaped part on the intake manifold, on the passnger side of the engine. It has a hose going into it on each side and a larger hose attached to an elbow on the bottom.
If you are coming up with your car on Sat. I can help you. I just replaced mine!!
As for your seatbelt, I believe they are covered under warranty forever. You'll just need to take it to a Mazda dealer.
Mike
I thought we showed you the BAC valve on Sunday??? It is a 4 inch cylinder shaped part on the intake manifold, on the passnger side of the engine. It has a hose going into it on each side and a larger hose attached to an elbow on the bottom.
If you are coming up with your car on Sat. I can help you. I just replaced mine!!
As for your seatbelt, I believe they are covered under warranty forever. You'll just need to take it to a Mazda dealer.
Mike
08-28-01, 07:16 PM
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The 89-91 NA don't have an adjustment screw on the BAC itself. The 89-91 also don't have the lean/rich adjustment screw located near the boost sensor and strut tower as the 86-88 models. Ground your initial set coupler (single green coupler near battery) before adjusting the idle screw located on top of the throttle body.
08-29-01, 01:15 PM
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Ok, I'll try that.
Should I ground the intitial set coupler before I re-adjust my TPS too? I think thats whats hurting my gas mileage; I must not have done it right.
Phungus did you find out whats wrong with your engine yet?
Should I ground the intitial set coupler before I re-adjust my TPS too? I think thats whats hurting my gas mileage; I must not have done it right.
Phungus did you find out whats wrong with your engine yet?
08-30-01, 09:45 PM
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bump
Just consulted the factory manual; makes more sense to me now. I'll re-re-adjust the TPS tomorrow
Another thing, now my fast idle is acting up. It revs to 1500, stays there for a few seconds, then it lets off and drops to around 1200 or so, then back up, and so on. I think its the thermowax, but maybe its just me messing with a perfectly good TPS. Anyways its time to put an end to these gremlins. I've been reading up and it sounds easy to test the BAC, and now that I know how to ground the isc I should be able to narrow it down some.
Just consulted the factory manual; makes more sense to me now. I'll re-re-adjust the TPS tomorrow
Another thing, now my fast idle is acting up. It revs to 1500, stays there for a few seconds, then it lets off and drops to around 1200 or so, then back up, and so on. I think its the thermowax, but maybe its just me messing with a perfectly good TPS. Anyways its time to put an end to these gremlins. I've been reading up and it sounds easy to test the BAC, and now that I know how to ground the isc I should be able to narrow it down some.
08-30-01, 10:24 PM
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Try this site for visuals of parts http://home.earthlink.net/~burntoast/
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