Okay, first, let me start by saying, I have searched, and I have read a lot of stuff over the -SE idle issues, but the page in the FAQ is no longer available, so i'm kind of stuck high and dry. Kind of.

Let me start by describing what my car is doing.

I'm driving, and the first thing I notice is the throttle response is very horrible, and I can't "feather" my accelerator and cruise at a normal speed without either accelerating or decelerating. If I try to go fast, or try to accelerate very quickly it seems to be lacking power and not performing like it usually does. This was on the way to my classes this afternoon. I took a different route to my campus after my first stop light to avoid stopping so much and when I pulled up to school, it was no longer doing it. I thought it was weird, and it was done being weird on me. Came back out during my break and went driving to see if it was still doing it, it had stoped and wasn't being a nuisance that time either, didn't do it again until my way home from class.

On my way home, it began doing it again before I even left the parking lot. I tried to avoid stoplights again, and when I hit the final stretch of no stop lights or stop signs and I was just cruising, it felt like something that was sticking, came un-stuck. At that point I got the ability to cruise without accelerating or decelerating back, but it stil felt lacking in the performance area, and it still had the rising and dropping idle.

On another note, while it is doing this the whole car is vibrating, and it feels like its about to shake it to pieces.

Does this sound like the same old TPS thing? Or the sticking butterfly valve thing?

And if so, anyone know of a write up for both procedures? I don't really understand what i'm supposed to grease for the butterfly valve sticking thing, or how to get to whatever it is that i am supposed to grease.


okay, that's all I got, so flame if you must for not using the search (even though i did!) or whatever.

 

Fuel filter? TPS could be out of adjustment or failing. Check the smaller hose that comes from the air intake tube to the DEI chamber. Normally with the sticking rod in the throttle body, the idle will hunt back and forth at a stop or slightly off idle.
And it can be intermittent. Do you still have cats?
I think I may have a copy at work about the idle problem on SE's that used to be in the FAQ. I'll check tomorrow.

 

if you can't feather your idle that sounds to be mechanical to me. goto an autoparts store and purchase a can of throttle body cleaner, not carb cleaner. it has lubricants in. spray upper and lower plates well and work them manually with your hand. you can hit the two outer linkages on both sides too.
if your plates are sticking your tps thinks your in one spot while your engine is demanding a different. sometimes my engine idle would just stay high and slowly drop or the idle would do this odd, booopppp boooppp up and down slowly. sometimes it just took a second to blip the throttle good for it to go away or a minute.
i would also check your AFM flapper to see if it's dragging, should push open and close freely with a thunk.

 

Google cached version of page in archives

http://64.233.161.104/search?q=cache...-SE+Idle&hl=en

Once I get a webserver up I'll host a copy of it

Jon

 

What a find! Thank you!

 

you'll DEFINATLY want to check your tps adjustment. also, inspect the BACV for a bad connection or gasket leak. i had a problem with that little guy and suprisingly enough, it was causing my engine to idle rough. it was due to a bad gasket. it does sound like more of a tps issue though.

 

Could you explain some more about this BACV. The Haynes Chilton's manual does not mention that valve anywhere ( that i could find). As another proud GSL-SE owner i have been researching my low idle and the BAC seems to be the most probable culprit.

For the hunting idle that surges up and down i would suggest as stated above to clean out the TB and lube up all the shutters.
Good luck and tell us what you find.

 

this is wher e I got my Idle FAQ

http://members.ij.net/mrmazda/gslseidle.html

 

I just re-read my first post and realized I left something major out, what my RPMs were doing.

I don't know if this will make a difference, but it isn't hunting for RPMs, it's bouncing. It will start at 1000 and bounce to 1500 every half second to a second. It's constant and just goes up down up down up down. If I was to guess (it never sits on any RPM, it just bounces) and it takes about a second for it to go up and back down and then it does it again.

oh, and viper, when i clicked that link, it just took me to google and said "No Results found"

 

That's called 'surging' or 'SE surging' and has been talked about here at length.

What you'll need to do (the short-term fix) is grab a 12mm box-end wrench and remove those two shiny chrome cap nuts that hold your air pipe onto the Throttle Body. Once removed, take a can of silicone lubricant and spray it on each of the throttle body rods in the primary and secondary intake. You don't have to hose the place down, just get some lube in there to allow the rods to move freely. Then replace the airpipe. Look at the outside of the TB and you'll see that the TB rods go all the way through both sides, lube the outsides as best you can with the same stuff and then let it sit for awhile. The lube wil be drawn into the aluminum TB and lube the steel shafts, usually fixing the problem.

If you want to know why this happens keep reading. Otherwise, get to work;

The aluminum TB on the SE's has a minor design flaw, whereby it uses steel TB rods which are attached to the butterfly valves in the primary and secondary intake path (along with the 'secondary throttle' or choke plates). These steel rods will 'gall' the insides of the aluminum TB until there is a buildup of aluminum oxide which prevents the rods from turning smoothly. Once this happens, usually in the colder months (go figure), the TB rods will not react quickly enough to coincide with the BACV as it tries to adjust the idle speed. Thus, you get a BACV increasing bypass airflow to increase a low idle, then the air velocity picks up, allowing the TB plates to open, which increases the RPM. As the RPM comes up, the BACV shuts down to bring the idle down, and the TB plates close, dropping the RPM. You end up with a feedback loop that usually continues until, 1) the engine warms up, 2) you get tired of it and pay the dealer $3k to replace your engine (which still doesn't fix the problem), or 3) go back to the top of this thread and grab a can of silicone spray.

Mazda could have fixed this by installing Oillite bushings or even steel bushings in the TB for the rods to spin through, but that would have added to the machinetime for the TB and increased the cost of the intake assembly.

HTH,

 

Wow, thanks LongDuck!

I just have one last question, you said it usually just does this until the engine is warm? Well, when my engine is cold it idles weird, when i push in the clutch it holds the RPMS then it drops really slow, then when its warm it does this surging thing, does that matter? Or are those still symptoms of the same problem?

Oh, and sorry about the post, I didn't understand that's what Surging meant, i thought it just meant a slight raise in RPMS slowly at idle.

 

Same issue - hot or cold.

Usually, the problem goes away when the engine warms up because the -SE's have a heater hose that comes off the back of the water pump to warm the TB (and operate the Thermowax pellet - don't ask), that tends to expand the aluminum TB enough so that it doesn't impede the movement of the rods once heated up.

If your rods are particularly 'sticky' in the TB, then you'll experience this when it's cold or hot.

My 'surging' problem used to happen on cold start (on a cold day) and would run the throttle up to 3k rpm, drop down to 1k rpm, run up to 3k rpm, and do this over-and-over-and-over in about 2 second intervals, i.e., 2 seconds high then drop, then 2 seconds high, then drop, then... You get the idea.

Surging is pretty easy to fix, just takes some knowledge about what's happening and how to get to the rods to fix the problem.

RESIST THE URGE TO GIVE IT SOME $#!? (as in revving it like mad or driving it like you stole it in an effort to make it stop) - this will only result in you causing additional cold-start oil starvation damage on a cold engine, and will lead to more problems down the road.

(You wouldn't believe how many SE owners think the above is the 'correct method' of fixing SE Surging issues!!!). HTH,

 

Wow, Thanks again.

You should write a book with all this -SE knowledge that is inside of your head.
Hopefully this issue will be fixed tommorow, i've had a rough week between tonsillitis and exams. Thanks for all the help though, I really appreciate it.

 

Well, you're welcome. I hope you get to feeling better.

Anytime for a fellow -SE owner,

 

Hey Long Duck, are you talking about the rods that run through the butterfly valves to control their opening/closing? I sprayed those down near where they run through the body of the TB, and on the outside, but it is still doing the same thing. I tried to manually move the butterfly valves, and they didn't move very freely, they stuck once in the closed position and would barely close back down.

I'm going to try spraying them some more tommorow, it's night here and a little difficult to see.