Anybody know what causes this? This is a reoccuring thing. As I slow to stop with the clutch depressed the idle bounces between 1000 to 1700 then stops when I come to a complete stop. What gives?

 

I think there was a TSB for this right?

 

I'm having the same problem. Whats a TSB?

 

T.echnical S.ervice B.ulletin: sort of like a mini recall I guess...

 

How can I tell if a TSB has been done on my car?

 

When I had my engine replaced on my 93, I had the same problem. What it had ended up being was my idle control valve had a tiny piece of plastic jammed in it. This was after a dealer had done a diagnostic on the car with no codes showing up. I had pulled the idle control valve, and found that it was stuck open. This may not be the problem, but it's a place to start.

 

go to a mazda dealer and give them your VIN. they should have all the recalls performed on your car.

 

The dealer said all the recall work has been done...any other ideas??????

 

TSB and recalls are different. TSB are known problems that don't raise safety issues. Recalls are known problems that raise safety issues such as engine fire, brake failure etc.

Mazda is responsible for all recalls. However, TSB were fixed at their discretion on a case-by-case basis. It's primarily common problem fixing tips for Mazda mechanics.

Many sites have a list of TSBs. I think this site has it as well. I think it has to do with the idle control valve that someone mentioned. Do take a look at the list and start from there. BTW, unless you have an extended warranty, forget about trying to get the dealer to pay for it. The only thing they cover is recalls now.

 

I have that same problem.........But mine is an off and on thing....

 

I've gone through every TSB, SSP, recall, and M-tip on the FD, and nowhere can I find any reference to an idle fluctuation. If someone knows exactly what the bulletin number is, I'll post it up here.

 

I have the same problem on mine, but it doesn't seem to be as severe. I don't know what causes it, but I would also like to know if anyone knows where to check recalls

 

Check your mail this evening, Mr. Mahtab.

 

I think on the clutch inside the car there is clutch switch, when u press the clutch the switch send a ground signal to the ecu. If it's broken the ecu won't see the ground and it may cause somtimes to that. I used to have that problem and i found out that my switch was broken and i replaced it and now every stop it idle like the way it should 800 rpm. ALso it's a white switch. good luck

 

My car does this kinda sporadically. Sometimes it'll stick at 2000 rpm until I come to a complete stop, then it'll start bouncing between 1000-1700rpm. Sometimes it doesn't bounce at all. I haven't figured out why, but it started when I replaced my spark plugs and wires (took off the intake manifold, with vaccuum hoses and all). I'm thinking one of my hoses has a crack, or isn't attached correctly. I may have to pull out the carb cleaner and start looking for leaks.

 

BTW: I don't see any TSB about that on www.k-rad.com

 

It's not a TSB, it's an SSP(Special Service Program).
PM me with an email address and I'll send to Mahtab and anyone else interested, or someone can host it on their site. It's an ECU issue that only affects 93's on deceleration.

 

I started experiencing the same problem after removing the intakle and polishing. I suspected a lose vacuum line, but rechecked everything last week. It's possible one of the silicone lines has a leak. I did notice that some of the original hoses didn't adhere to their mating parts too well after I had removed them. I then replaced all of those with silicone. Searching for the problem.....

 

Here is the TSB that I was referring to. I don't know if this is the symptom that you are having. I gathered that you've looked at this one and it wasn't a match to your problem. Maybe someone can post the SSP or a link to all SSP out there.

Good luck...

12. ENGINE STALLS DURING WARM-UP / IDLE FLUCTUATION
Service bulletin #032/92, Category F, issued 12/23/92
Applies to 1993 RX-7 5-spd models with VIN of JM1FD3312P0208703 or lower

produced through July 2, 1992. Applies to 1993 RX-7 automatics with VIN of

JM1FD331XP0210513 or lower produced through September. 30, 1992.


Some 1993 RX-7 vehicles may experience stalling during deceleration with the

throttle released approaching a stop. This occurs during initial warm-up and,

sometimes after the car has reached operating temperature. Also, when idling

with the A/C on, engine speed decreases as the A/C compressor engages and idle

fluctuation may occur. The ECU has been modified as a countermeasure. The

modified ECU is designed to

Make air/fuel ratio adjustments to maintain stable idle at all temperatures

Turn off the A/C compressor when the clutch pedal is depressed or when the

accelerator pedal is released.



WARNING from DZ: The following parts may have been superseded by a

more recent TSB. Have your Mazda dealer check their own TSB list which should

be more up to date.)
Replace ECU under warranty with following part:
N3A1 18 881R ECU (Federal 5-speed)

N3A2 18 881R ECU (Federal Automatic Transmission)

N3A3 18 881R ECU (California 5-speed)

N3A4 18 881R ECU (California Automatic Transmission)

 

Here's the SSP regarding ECU replacement for idle fluctuations. Only 1993 models are covered. It's in PDF/Acrobat format so it takes a bit to download. Can someone host it elsewhere?(Please ask first).

 

I get the idle fluctuation, 1993, but it always fluctuates at idle but idle will settle when the lights are on!! Anyway have that problem? ECU was replaced in 1993 under warranty.

 

well for me was getting it and it made me mad as hell, but come to find out that my O.E.M, main kat was clog and i bought a used one, when i put it on it stop now problem and no smells from the kat. about 4 montjhs later i got it again so now i just bought the random tech main cat. so we will see, if you have more than 50,000 on your kat you should look into gettting a new one

 

it is caused by the ECU. Got my PFC and stopped. I had ECU N3A3 Cali 5 spd.

 

hmm.

I have a '93...
my idle starts hunting when I disengage the clutch.
It will continue to hunt while the vehicle's stopped, but will sometimes settle.
It seems to be affected by ambient temperatures, and I can make it more quickly settle by turning on more accessories.
And my idle is always higher than what is set on the PFC. I have 900rpm set, and it will idle at 1,100rpm.
If I change the idle to much lower, it will hunt even more severly.
On cold mornings (maybe lower than 40C) the idle will keep at 2,000rpm until about 15 minutes after the thermostat opens.

I have a PFC and RX-7 Store just re-did most of my vacume lines during an engine install.

I was thinking of checking my map sensor and idle control valve.

Can this also be caused by shitty tuning?

arghh.

 

i agree, it is a software problem in the ecu. i bought my 7 with 97000 mi and it idle flucked as described by others. seals went and i installed a port motor from pettit. exact same idle flucks. installed new microtech programable and the problem is long gone.................