KLZE swap, some issues off the bat

[Daninski]

yea I have used the screw on TB to help with idle, but I have never just used that screw to set idle. I've always jumped TEN & GND hooked up my tech meter on the coil or spark plug wire, set the idle with the throttle stop screw which is where you would want it to be when you let off the gas pedal. and I turned the air screw 1-2 turns I believe then pulled jumper out and works fine. but we all have our own ways.

For clarification the throttle stop screw is factory set and is not suppose to be touched,,,ever,,,except for guys from Picton who's car breaks down during the biggest car show of the year with Danny Koker guest celebrity.

[mazdaspeed23]

Hahaha, funny guy you are Dan. The throttle stop was definitely not set by factory on my car for sure. That thing was way out of wack. But hey I got her all fixed top shape now.

[Elli]

We learn about each other a little more every day. I can see a long and frustrating relationship between her and I.

REAL bucky when cold... but holds idle. When the bucking stops, the idle stops. So warming up seems to change it. I know it doesn't go into "closed loop" so I'm confused.

Anyway, changed the fuel filter, the last one had a bunch of black stuff pour out of the inlet side. Held idle on the way out of the garage to the parking lot, may have noticed a little buck... but if that's still around after I get idle set then I'll log that then.

[mazdaspeed23]

Keep us postedd once you do the idle

[Elli]

Well, a few details about idle...

When it holds it, it holds it right around 1,100 RPMS. If it's low and hunting... 700ish, if it's high and hunting, 1400ish. So when I get death, it's not like it's fighting to hold any particular RPM... it goes to needle flat, sputtering and dying. I will adjust the idle but I think I'm gonna have some trouble since when this thing is warm... I couldn't start the car and jump out to adjust anything before it dies, and there's no point adjusting it with my foot on the gas.

So if this fuel filter doesn't work, I'm gonna change the plugs, wires and rotors and clean up the cap (since it's one of those fancy aftermarket modified once costing 60 bucks before shipping). Will keep updating.

[davmac]

Through this whole discussion what I think I'm hearing is that the engine will high idle when cold, but is misfiring. Once the engine warms it will not idle at all. I think there is a fundamental problem. Are you certain the mechanical timing is correct? With everything assembled and the engine in the car I know you do not want to check this. If the base mechanical timing is off (timing belt is off by 1 or several teeth) then it would explain all your symptoms.

You'll have to pull all the front engine accessories and the timing belt covers. Remember that the timing marks on the crank shaft timing belt pulley and the camshaft gears only all line up with their marks every 2 revolutions. Personally, after all that work I'd just re-install the belt and double check the timing marks are lining up.

I wish an injector or fuel filter or spark plug or spark plug wire was the answer, but it really sounds like this engine has not run right ever.

[Elli]

Dav(e?), I'm sitting in my garage at work right now rapping myself in the head.

So this engine, when it ran in the probe, spun like a top.

I took it to Advance and had them check out the battery and alternator, cuz... I wanted to.

He had run the engine to 2500, and turn on the high beams and fan... this thing went immediately down to "HELP ME I'M DYING Revs Per Minute" turned the fan off... beautiful. Even with the gas pressed!

So I'm like "...ground."

Turns out there's a bracket that bolts to the tranny has a ground attached to it. So i followed the black/yellow ground wire... hooked up. Since the bracket didn't do anything else when I put the engine in I never bolted it down... just rested it on the stud. I just went through with an ohm-meter and started straightening everything out. Found that, hooked it up... now this car starts in one crank, JUST LIKE THE PROBE DID! So I'm gonna go drive around now and see if I have the same problem at temp. (I keep saying at temp like it's going to go into closed loop )

[Elli]

Sho' nuff. Worked like a charm. It still hunts around 1K... and when it gets sick of that it idles around 2700. Next I'll swap out the o2 sensor and actually find idle. At least I can drive in traffic now.

I'm really good at stuff the 2nd time around.

[mazdaspeed23]

good to hear you found most of the problem. However ive had bad o2's before and never had this problem your having with the idle ( not saying it cant happen). Sure the TPS is good? or set right

[Elli]

Well, I used the fan trick, and set it so the fan was just barely off.

[Daninski]

Crap plugging your filter will cause bucking and stalling for sure. One tank of dirty gas can ruin your day, happened to me. I'd say remove your fuel line from your filter and pump some fuel into a big clear bag then see if a lot of crap is present, your tank may need to be cleaned. If the bucking persists check the filter screen next to your fuel pump. Next, your a bone head for not hooking up that ground bracket but hey your in good company here. Finally reset you TPS then your idle with Ten and Gnd jumped. Use a tach gauge not the one one your dash. Good Luck

[Elli]

Yeeeah, I was like, "This ground strap is bolted to metal, good." Then on a totally different thought I said, "This bracket isn't really holding anything, I'll just leave it unbolted." Never put the two together... but hey, even Charly Gordon got smarter over time.

[davmac]

Congrats
I'm glad I was wrong about bad mechanical timing. Finding a bad ground is a fundamental problem - so I'm glad you got that one out of the way.

Now you can turn your attention to the crazy high idle. 2700 rpm is hard to explain high. Even cold start idle is around 1500 and certainly less than 2000 rpm. Again, there may be some fundamental issue and an easy fix. My thought: Throttle cable for some reason is holding the throttle plate slightly open. Now that the car will run you can fool around under the hood.

Eventually you'd want to jump TEN and GND and set warm engine base idle to 600 - 700 rpm using the throttle body idle screw. After that fine tuning of the ECU controlled idle involves checking engine coolant temp sensor (green 2 wire is used by ECU), TPS and idle air controller (IAC).

[Daninski]

Eventually you'd want to jump TEN and GND and set warm engine base idle to 600 - 700 rpm using the throttle body idle screw. After that fine tuning of the ECU controlled idle involves checking engine coolant temp sensor (green 2 wire is used by ECU), TPS and idle air controller (IAC).

Didn't I already suggest idle and TPS???? I'm curious, you propose to 'fine tune' involving the coolant temp sensor, what exactly are we doing with /to the coolant sensor that will fine tune the motor (please refer to repair manual)? I'll let the IAC ride for now.

[davmac]

Didn't I already suggest idle and TPS???? I'm curious, you propose to 'fine tune' involving the coolant temp sensor, what exactly are we doing with /to the coolant sensor that will fine tune the motor (please refer to repair manual)? I'll let the IAC ride for now.

The ECU fine tunes the idle using the coolant temp sensor input. The only thing we can do to it is test it to make sure it is sending a good signal and confirm wiring and connectors are good. Air in the coolant can also be a problem because the coolant temp sensor will then send an erratic signal. The IAC is an idle control device - an ECU output. Again, nothing we can do to it except test and confirm it is good.

My post is just a reminder to get back to checking these items as Elli finds and fixes ground connections, etc. I agree my post is redundant. TPS and idle screw adjustment is in almost every post.