alritzer

Hi guys, I finally got around to starting my 86 N/A after rebuilding it over the winter. It started really easy. Probably with 10 secs on first crank. After the engine was running myabe 20-30 seconds, I let it return to idle. When I went to check the engine for leaks and such, I found that on of the connections to the ACV was on fire. I had gloves on so I just reached down and snuffed it by hand. But the problem is that the connector has been burned off. The connector that burned was the one that sits toward the back and on the right side of the ACV.

Can this part be purchased separately? Why did it burn?

The engine idled really good at about 1800 for several minutes and then started getting wide fluctuations in rpm. Say 1200 to 1700 continuosly.


thanks...........

Wankel7

Uh, cut off the charred wires and install some connectors your self?

alritzer

I can cut away the charred wires but there is nothing left to hook them back up to. I'm going to have to find that piece. The ACV has two electrical connectors. One with a white connector and one with a black. I need the black. I don't know if there is any difference in them.

WAYNE88N/A

So the solenoid that had the burned wires was the back one on the ACV? That's your split air solenoid, responsible for sending air to the cats.

These solenoids like to short out and start electrical fires, blow fuses, and toast ECU's for some reason...

Do you have to have full emissions on the car?

jhammons01

If you want to fix it right you just need to buy ( or ask if someone will just give you) those same connectors and start stripping back the harness until you get enough fresh unburnt wire to work with. Then attach the new connectors (hopefully whoever you get teh new connectros from will cut the wire way back and give you something to work with.....like 9" back from the connector).

There are various ways to attach the two wires but I would use solder. You can get some cool connectors from radio shack or Lowes that allow you to just put the two wire ends into them and then snap them shut....striping and connecting the wires with one swift motion. But me? I would feel better with good ole solder.

Your idle lurch is from a vacuum leak somewhere in the vacuum harness. C'mon Ash. Tell me you replaced ALL those hoses when you had it apart. Even the brake booster vacuum lines?Or worst case your intake manifolds are leaking at one of the gaskets. Did you check teh FSM for torque specs and tightening patterns?

alritzer

Yes, I torqued everything to specs. But no, I didn't change all of the hoses. I don't remember anybody saying anything about it and I sort of followed the video from Atkins. Could the surge be related to the ACV? Or, maybe its just because its a new rebuild.

The wire burned off right at the ACV so if I can find a replacement it will be really easy to repair. Screw it in, plug in the connector.

jhammons01

No, the surge is most likely a vacuum leak. Your vac hoses are 20 years old and they are dry and brittle and they'll leak causing surging idle. You might be ok just replacing the external ones but the ones on top of the OMP banjos may screw you up.

Go get some new line at any auto parts store. (it will be thicker than the stock Mazda line) Buy about 10 feet. $20 bux worth. Get a nice pair of snips and a stool and sit down and take One (1) line off at a time and replace before moving to the next. Just eyeball the length, cut the new one and put right back where you found the old on. There are few large ones like the ones going to your break booster. you need a few feet of that. Take your time do it right and then let us know how the idle is after.

If you can replace those two lines with aftermarket connectors then by all means have at it. I did not know if you wanted it to be just like original or if aftermarket was OK with you.

WAYNE88N/A

Ain't gonna do any good replacing the wires at this point- you have a smoke checked solenoid, so you're going to need to replace that first before you fix the wiring...

You may have fried the ECU's output circuit for the split air solenoid, which means the system would no longer work correctly anyway, which means replacing the solenoid and wiring is a moot point...

You can check the ECU by running a couple of tests, if you're interested...

HAILERS

Split Air Solenoid only comes on when in fifth gear.

Yes, just buy a solenoid form someone on the forsale section. Just screw it in and plug it up. There is a small spring and poppet valve inside/under the solenoid. Try not to drop or lose either.

To see if the thing works. prior to putting the new one in the ACV, connect the harness up to the solenoid, and turn the key to ON.

Then with the poppet and small spring resting in the bore of the solenoid, have someone put the transmission in fifth gear. If all is well, the poppet will be magnetically attracted to the solenoid and you will be able to invert the solenoid and the poppet will not drop out thru gravity.

The harness probably caught fire because the previous owner (squid), tried to unscrew the solenoid from the ACV with the harness still connected and broke/twisted the two wires at the solneoid. Then later they arc'd and caught the harness on fire. imho

alritzer

Yes, I'm interested.

WAYNE88N/A

Lol, that's a cheap shot, flyboy wanna-be

Ash- Hailers pretty well summed up the tests for you...Me personally, I'd just check for a good 12v in any gear but 5th, and 0v in 5th gear at the ECU pin (0v would mean that the ECU successfully put a ground on the split air solenoid, which would mean that the circuit is working). Hailers likes to tinker with things and reverse engineer the car, but he did quote a valid testing procedure in his post, to his credit. If the Air Force would have educated him a little better, he'd be doing the meter thing at the ECU also....

alritzer

Hey guys, I saw in the past posts section that the ACV can actually be removed and plated over. Is that a viable option? What a pain in the neck.


ash

WAYNE88N/A

Depends on if you have emissions testing or not...

alritzer

The car will probably be registered in WV. No emissions testing there. But, if I register it in PA, they do have emissions testing. So I guess it doesn't really matter. Can I just block off the ACV or should other things be blocked / removed also. The post I saw didn't say if just the ACV could be removed.

WAYNE88N/A

Again, it depends...

If you have the cats still on the car (even with no emissions you may still wish to have the cats), you'll need the ACV to provide the air for them (you could rig something up from just the air pump, but I won't go into that just now)...

The ACV also provides an anti-afterburn valve on decel for driveability...

There are pros and cons for removal, and there are lots of threads that discuss the subject, if you want to search...

FWIW, I still have my ACV on the car even though I have no "working" emissions anymore. It's not like it's in the way of anything. Besides, if your state/ city/ county does decide to instigate emissions testing (more and more are doing this), have the ACV already there makes it much easier to get your car back "up to snuff"...

Short answer- yes, you can remove and block the ACV. Without it, you might as well remove most or all of the rat's nest, because you will no longer need the relief solenoid valve and the switching solenoid valve...

alritzer

One more question. I stopped by the garage on the way to school just to start it up and let it run for a while. When I first start it, it runs really good. Idles at 1800 and only a little pop from the exhaust once in a while. After 6 - 7 minutes the bad idle starts. I watched it more closely today and the idle speed wanders from 1600 - 1800. I let it run for about 12 minutes total and the idle didn't get any worse nor any better. Does it still sound like a vacuum leak?


thanks again

jhammons01

Still............................................. .....sounds like a vacuum leak. Did you replace all the vac lines yet?

My motor has 1400 miles on it. idles at 600 with air off and 775 with air on. "Smooth". before the rebuild the idle would bounce all the time and with the A/C off it would die at the bottom end of the 4th bounce everytime. TPS, Idle screw, etc etc........all came down to the vac hoses were so old and dry that when I tried to unhook them they just crumbled.

I figured that I would work out the idle issues after the fresh motor was put in. I didn't have to......the idle issue was gone becuase I put all new rubber on the rebuild.