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Strange idle

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Old 10-12-2011, 08:03 AM
  #26  
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just a question for the guys with idle problems, do you still have the screens in the intake tubes? ive heard when they are removed/damaged it can cause idle problems. did you guys clean the ess?
Old 10-12-2011, 10:45 AM
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Originally Posted by jsudz08

It also "hunts" at around 750 or 800 RPM, starts to shake like it's going to die, then jumps up to around a 1000 for a few seconds...then makes it's way back down.
Originally Posted by DarkHelmet
bump it back up!!

im also having this problem. i'll pull up to a red light and the entire fricken car will rumble and shake for a few seconds then stop for a few seconds and just repeat this process.
Originally Posted by Myterial
No I havnt found a solution yet. 1 person says they fixed it with their ap but I don't have one so I'm boned their. I havent found any vacuum leaks either.

neutral switch on the tranny. causes the hunting idle exactly as Dark Helmet and sudz describe.
Old 10-12-2011, 11:32 AM
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Originally Posted by zoom44
neutral switch on the tranny. causes the hunting idle exactly as Dark Helmet and sudz describe.
so whats the solution?
Old 10-12-2011, 12:11 PM
  #29  
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get a new neutral safety switch. Mazmart sells them for about 40% off what the dealer will sell it. I had AAmco do the work since I couldnt get to it in my garage at home.
Old 10-13-2011, 09:17 AM
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Ok so looking at the couple of options that were presented. My airbox is completely stock except for k&n filter (I know some people hate them). Cleaning the ess. I looked at where it's at.... Do I just take it off and wipe it down or is there a better way to do it? (not much in search for ess). 2nd the neutral safety switch..... I can't find it on mazmarts website and there is no search on it either. Am I just dumb and missing it?
Old 10-13-2011, 10:53 AM
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ess is on the front of your engine on the bottom if that makes sense. looking from the top (hood open) its kinda underneath/right of the e shaft pully "crank pully". i remove mine from the bottom, think its a 10mm bolt and it has a small harness conected to it. you can just wipe it off or use some brake clean. remember to do the 20 brake stomp afterward
Old 10-13-2011, 12:38 PM
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Its not the neutral switch or that other stuff. $50 says that if you read the front O2 sensor you will see the afr make a lean dip just after the idle bobble (slightly after due to delay between when it occurs and when the O2 sensor sees and reports it)

It can be tuned out with an Accessport.



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Last edited by TeamRX8; 10-13-2011 at 12:44 PM.
Old 10-13-2011, 01:38 PM
  #33  
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team could be right as well. but i know mine and several others who had a similar issue had bad neutral switches.

call mazmart for the switch.
Old 10-13-2011, 06:37 PM
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Originally Posted by TeamRX8
Its not the neutral switch or that other stuff. $50 says that if you read the front O2 sensor you will see the afr make a lean dip just after the idle bobble (slightly after due to delay between when it occurs and when the O2 sensor sees and reports it)

It can be tuned out with an Accessport.



.
Anymore insight into this? I noticed the dip as well through logging. I played with the Fuel VE values at idle to make this phenomenon disappear about 80% by increasing the VE values (leaning the mixture out). Do you have a better method for this?

-Lawrence
Old 10-14-2011, 09:09 AM
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The neutral safety switch is usually a hunting idle that rythmically goes from normal idle to about 1200 rpms......

Inreasing the Ve values increases the amount of fuel...it is a multiplier not a Lamba Value

Usually rough idle is too lean and too low...so giving it a bit more fuel usually is the correct thing to do. Mazda does some major timing trickery to get it to idle as lean as they do...and anything that changes where the load value at idle is will take it out of the sweet spot and result in crappy idle.

Check yor trailing plugs /coils as well...you won't notice anything much with a trailing coil missfire when driving....but your idle will be horrible because it is the primary ignition event at idle
Old 10-14-2011, 10:51 AM
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Originally Posted by dannobre
The neutral safety switch is usually a hunting idle that rythmically goes from normal idle to about 1200 rpms......

Inreasing the Ve values increases the amount of fuel...it is a multiplier not a Lamba Value

Usually rough idle is too lean and too low...so giving it a bit more fuel usually is the correct thing to do. Mazda does some major timing trickery to get it to idle as lean as they do...and anything that changes where the load value at idle is will take it out of the sweet spot and result in crappy idle.

Check yor trailing plugs /coils as well...you won't notice anything much with a trailing coil missfire when driving....but your idle will be horrible because it is the primary ignition event at idle
Thanks for your reply! I definitely know its not a neutral safety switch in my case since I have a 6 speed automatic However, increasing the ve values definitely leaned the mixture more, as you said it is a multiplier. If you take 14.7 and multiply by 1.08 instead of 1.04, it would be leaner, not richer. Point being, by leaning the mixture a tad more, my idle is much more stable than before. However, I would be curious to see what TeamRX8 has to say regarding specific tuning strategies to eliminate the idle hunting using the AP.
Old 10-14-2011, 11:13 AM
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You think the multiplier acts on the Lamba/AFR value?...or the actual fuel amount the PCM injects? Or on the actual calc load the engine "sees".....?

Only one will result in less fuel seen from an increase in the Ve table


Maybe I am an idiot
Old 10-14-2011, 11:49 AM
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I'm positive the fuel VE acts on the main fueling table. It may also have an affect on other tables as well, but I am not sure right now. I really find the help file included with access tuner race program very helpful. Also, its fun to play around with different settings and explore how each table interacts with one another.

-Lawrence
Old 10-14-2011, 11:52 AM
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Very important to figure that out
Old 10-15-2011, 12:43 AM
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I have this same issue. At idle, it bounces between 1,000 and 750 rpms.
I just recently cleaned the SSV and the idle didn't vibrate as hard but it fluctuates still.

I have an '04 Auto GT with 63K on it.
Mods - AEM CAI
Old 12-02-2011, 07:05 PM
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I know this thread is a couple months old, but I figured it'd be smarter to ask in this thread. I have the same issue as most other posting in this thread.

It's a rough idle that varies from about 750-1000 rpms. Occasionally it drops way down to 500 but shoots up to 1500 for a second, then back to 1000. I'll clean the air filter as soon as I can (Mazdaspeed CAI).

I recently installed a BHR ignition set-up including new plugs and wires (within a month), replaced the SSV solenoid (threw the engine code), done an oil change with Idemitsu, Optima Red Top battery (brand new). Other details on the car: 2004 m/t 54000 miles hi-flow cat, exotic speed exhaust. My engine light is on now due to a faulty fuel cap (already ordered a new one), I know that I do have a bad motor mount.

Like I said, I'll clean the air filter ASAP, I checked the MAF sensor didnt seem dirty, but I clean it if its recommended. And I'll do the reset. Anything else I should do? The motor mount is going to be changed, just getting my finances situated
Old 12-05-2011, 02:38 PM
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BC

Another NOOB question by me, 2004 6spd 88,000 km (Canada)

My car seems to idle fine rpm stays at 750 or so, but my shifter vibrates like crazy. Is this normal?

The car seems to run great Outside temp here is between -5 deg C and 15 deg C. I have only had it 3 weeks and have read alot of post on this forum, so I am a little paranoid about EVERYTHING strange the car dose.
Old 12-29-2011, 08:23 AM
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I have an issue similar to that that you are having, but mine constantly goes up and down until it is warm then it is good. I don't know what a purge solenoid is or where it is located, but if its super cheap im going to try that. Mine happened after a new engine installed though, so probably not gonna fix that, unless its in the UIM, which I soaked in degreaser and water to clean it out. Maybe F'd up whatever that sensor is inside the UIM.
Old 01-03-2012, 08:39 PM
  #44  
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So far, I've cleaned the maf, changed plugs, wires, and coils, I still have to crank for a little longer sometimes for it to start, and it idles very rough...even worse anytime anything electrical is on, ie. fan for heater (worse with AC) rear window defrost, seat warmer, getting pretty frustrated...not sure what to change or clean next, really do want to get this straightened out though.
Old 01-03-2012, 08:59 PM
  #45  
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have you checked your electrical connections? Test your battery and alternator.
Old 01-04-2012, 10:35 PM
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i just purchased a 2004 6 spd and it seems rough at idle, just below the 1k mark. i havent seen it fluctuate between below the 1k (lets say 750 rpm for ***** and giggles) to over 1k like you described earlier. it seems to just stay below 1k at idle but is still rough, not sure if it coincides with the issues described but any advice to reduce a rough idle is welcomed
Old 01-04-2012, 10:38 PM
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^have you taken any steps, or followed any of the instructions already mentioned in this thread?
Old 01-05-2012, 02:46 PM
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Originally Posted by wahkupup
Another NOOB question by me, 2004 6spd 88,000 km (Canada)

My car seems to idle fine rpm stays at 750 or so, but my shifter vibrates like crazy. Is this normal?

The car seems to run great Outside temp here is between -5 deg C and 15 deg C. I have only had it 3 weeks and have read alot of post on this forum, so I am a little paranoid about EVERYTHING strange the car dose.
mine too stay on 750
what really is the normal rpm at idle.
mine has always been at 750 since day one for 5 years.
it only goes beyond 1000 when engine not warmed up.
the shift *** vibrates but not like crazy.
and i thought this was normal.
Old 01-05-2012, 03:17 PM
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^That IS normal
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