Bad Idle...

[christi]

Hey.
Couple of questions..

The car is running fine after start up, every once in a while going up a steep hill she'll lose power, but it has lessen since the guys changed the OMP the other week. I have a new issue. One we think may fix it...

The motor is healthy none the less, I don't think she's going to "blow up" any time soon...

I went to Longmont last night to take a drive and chill - upon leaving the car didn't want to start well again, once warmed up, she started idling like total crap. Where as going from 1000 RPM to 500 RPM to almost dying.

For those that met Jarod a few weeks back when changing the OMP, he is thinking it's a few things:

Spark plug wires
Coil packs
cleaning the MAF Sensor
De-carboning of the car.

He also thinks the spark plugs may be bad again. Here's what they looked like when they were changed - How the car ran, who knows? I ask myself the same question...
http://yfrog.com/h8668hj

What do you think?

[phearless]

Yes, I estimated all those things. But replacing them won't be enough.... I need to also know WHY they went bad, or I'll never be able to truly "fix" the problem. I honestly think the de-carboning will solve the problem with the spark plugs fouling... which may also solve the plug wires and coils going bad.
Also, your power steering pump is starving the engine, at idle. When you turn the wheel, under no throttle, it drops as low as 200rpm, and I'm not sure why it's doing that.

I need to take my multimeter, when I go down to CSprings, for drill, and check the numbers against a factory service manual, just to be sure. I don't want you to spend money on parts, just to find out none of that crap was needed.

But, before anything else, you gotta get the de-carboning done, and fix that damnable exhaust leak.

[chickenwafer]

Start with the simple things, pull the plugs and see how they look. Replace them if needed, if not clean them up.

Bad coils won't effect your idle too much, there is very little ignition output required (plus FC's have tank coils). I would lean towards the MAF sensor being dirty or not getting straight airflow. MAF sensors are very sensitive little boogers.

Make sure your spark plug wires are on good and tight and have clean connectors. Replacing them couldn't hurt if they are old. You can measure the resistance (ohms) and see how good they are.

It also might not be a bad idea to run some fuel system cleaner (I like Lucas fuel injector cleaner) through the motor to make sure it isn't a stuck/dirty injector.

[christi]

I just recently changed the plugs though, not even 1.5 weeks ago. you think they're bad now?
Should I do the de-carboning after chehcknig the MAF?

[speedjunkie]

BS! THOSE are the spark plugs we just put in?!?! Wow. I'm thinking it's burning too hot, but I could be wrong since I don't remember all the signs by looking at the plugs. I don't know how that could be the case since you have a stock computer (right?), but you never know.

[reconbygod12]

could be a faulty coil pack or even could be that the spark plugs werent gapped properly

[phearless]

could be a faulty coil pack or even could be that the spark plugs werent gapped properly

You don't gap rotary spark plugs. If they're fouled, again, it's because she's got dirty trochoid housings.

[christi]

No no, those arent the spark plugs we just pulled out, those were the others. Sorry. I wasn't clear ha ha. I'm not sure what the ones we just put in are like, but the sound of how the car starts up and idles... makes me wonder...

Eric changed them for me, since I couldn't get down in there very well.. I think he gapped them pretty good, though.

[chickenwafer]

Which plugs did you buy? IF you got the NGK's made for the 13b they should be pre-gapped.

Maybe a spark plug wire came loose and fell off? You can peak down there and check easily.

[speedjunkie]

You don't gap the plugs that we got for the car, which are the same type in the pic she posted.

You scared me for a minute, I was thinking those were the plugs we just put in LOL.

[christi]

Sorry for being a little stupid. I really haven't messed with these cars in so long, my semi-knowledge of them has kinda shorten.

Eric.. You should honestly hear how she sounds like now. I'm not gonna boot her up until the weekend or so, but...

I guess I'll start out with the MAF cleaning and De-carboning? Mazda better, or can you actually do it yourself with ATF?

[phearless]

Sorry for being a little stupid. I really haven't messed with these cars in so long, my semi-knowledge of them has kinda shorten.

Eric.. You should honestly hear how she sounds like now. I'm not gonna boot her up until the weekend or so, but...

I guess I'll start out with the MAF cleaning and De-carboning? Mazda better, or can you actually do it yourself with ATF?

In the name of the gods, Christi! Don't EVER pour ATF into your trochoid housings! You'll do to your apex seals what Ike did to Tina!

[iani1.1]

its normal for FCs. usually most if not all FCs ive driven that hasnt had a rebuild or whatever usually idle like crap after a long trip. give it a couple days or a day to sit and itll idle fine.

after a long trip (colorado springs to albuquerque) on my silver fc when it was still stock it idled at about 500-350 when i got to new mexico. it never stalled or died once while i was there and got it home no problem. left it in the garage for about 2 days idled fine once warm.

carbon doesnt affect the idle, it does definitely affect performance. the ignition system should be alright. wouldnt hurt to clean the afm or de carbon it. i use the water injection treatment jus cause its free lol.

also there's an idle screw on the top of the intake manifold you can adjust if your feeling sketch about the idle.

[chickenwafer]

Please, don't use ATF. It works, but it's risky. ATF is a highly corrosive liquid (which is why it eats carbon), but it also destroys the chrome-plating on the housings, oil seals, pilot seats, coolant o-rings, etc. Soft rubber, like the coolant o-rings, are especially venerable.

It's OK, if you feel like risking it, to pump some ATF in through the leading spark plug hole, turn the motor over by hand with a socket and ratchet on the e-shaft nut, so you get some ATF in each working chamber. Then fire the car up immediately and let it burn off- get the motor up to full operating temp and drive it under load.

I mean the stuff literally eats carbon...what do you think it does to soft parts in your motor?

An easier but marginally less effective procedure is water-injection like Ian said. Find a vacuum nipple on the UIM that feeds both rotors (this is key), hook up a vacuum hose to it and run to a jug of distilled water. You want distilled, not filtered, not tap, nothing but distilled.

Start the motor and let it get up to a stable temp (at least 100*F coolant temp) then have a friend hold the pedal at 2500-3500rpm and stick the vacuum hose you previous attached into the jug of water. The motor will bog slightly as it starts to suck in the water, so have your friend adjust their throttle position accordingly to keep the rpm at least 2500. Suck through the entire gallon and your motor will thank you later.

When you're done, remove the vacuum line and connect whatever you disconnected or cap it and go for a drive, and take the motor to red line a bunch of times and thrash it around.

[iani1.1]

Yea distilled only. But 2500 is kinda high. Typically above 1500 gets most carbon out. Above 2500 just burns it off almost immediately.

I usually feed it through the LIM.

With atf you have to replace the spark plugs after cause they usually get pretty fouled. A teaspoon for each rotor face is more than enough.