daem0n

I saw something similar to this in the search, but not quite the same thing. Anyhow the car runs great almost all the time, but if I put the A/C on and am running in 3rd or 2nd and I down shift, unless I shift EXTREMELY fast, the car will stall as soon as I take it out of gear. It won't happen in the higher gears. When the A/C is on, the RPM's dive too fast, and if they hit zero the car will stall. The only thing I can do is shut the A/C off when I know I'm slowing down. This isn't a horrible problem, but it's just annoying. I read somewhere that this could be the clutch switch either being warn or just coming on too late. Anyone else have any ideas? Thanks a lot, -Joe

777rx777

Which ECU are you running? My car did the same thing.....

It would die in neutrol at stop lights and stuff


Maybe you need to adjust your valves...hehehe

lzyassmofo

my rpms bog down at idle with the ac on. theyll go from like 900-1100 rpms to like 6-750 depending on how hard the ac is blowing. and on a hotday if i have my ac on, the car will barely start, and definetely die at idle. i know my problem is some of the programming in my EFI ecu, combined with my light weight flywheel and pulleys. so back to Tripoint to get everything sorted out.

daem0n

Running the stock ECU, so shouldn't be a problem since almost everything is stock for the moment...I don't think it's the valves :-P

dclin

iTrader: (4)

Read the TSB and see if this applies to your car, #12.

http://www.rx7.org/public/3RD.html

Also, could be a sign of low compression. Take it to a Mazda specialist familiar with the FD and have them do a compression check.

daem0n

yeah, I don't know how you figured that out - or remembered about it, but that's exactly it. Thanks a lot for the help. As for the fix, I guess I'll wait for the PFC or something. But thanks a lot, that's at least re-assuring.

daem0n

one more question not related to the first...In the TSBs where it says to replace a part with a modified design part #FD etc, is this part already modified and if so, where do you order it from, a Mazda dealer? and I guess, if it's not modified that answers the question - do it yourself :P Thanks, -Joe

TailHappy

For what it's worth, my car would stall every time the AC was on and it was in gear. If I would put it in N right as I pushed in the clutch, it would always drop to idle just fine. Replaced the clutch switch (which is right on the clutch pedal and takes less than 2 minutes to swap) for less than $10 and the problem's gone. If you have a PFC, the sensor screen will confirm that the switch doesn't work.

Coulthard Fan

Anybody have a part number for the clutch switch?

TailHappy

Sorry, thought I had it but I didn't write it down. Hopefully someone will have it cuz otherwise good luck trying to describe it to the Mazduh dealer!!! They swore to me there wasn't such a thing until I made them pull out their shop manual....

Coulthard Fan

the part # for the clutch switch is HF05-66-4D0

daem0n

thanks for the part #, I'm going to pick one up

r1owner

Let us know if that fixes the problem.

daem0n

I'll keep you posted - I'll try to get one tomorrow, but knowing the dealerships here it will take them 6 weeks to find the actual part.

Coulthard Fan

So I replaced my clutch switch because I have the intermittent stalling with the A/C on, and the problem has not gone away. Getting a lightweight flywheel last year probably didn't help either.

I've read the TSB and I know that the original owner had the updated Mazda ECU put in which was "supposed" to solve the problem, but the stalling resurfaced at the end of last summer. Of course, I waited until now to fix it

By the way, figure on more like an hour to replace the switch. It was kind of a pain in the *** to get off because you have to move the wiring box next to it to remove the switch itself.

So I think my old switch was fine and I just need to tune the car up. Oh well, I figured may as well try the easy stuff first.

TailHappy

I'm not sure that you replaced the switch I'm talking about. It's at the top of the clutch pedal. You remove one nut, pull the wiring harness out of it and it slides out. Put the new one on and you should be done in 5 minutes. I can't think of any box that would have been in the way.

For what it's worth, I also have a 8.5lb flywheel, and my car only stalls about once every 3 months or so now, as compared with every time I pushed in the clutch. So I don't think a light flywheel should be an excuse for stalling. I also put in a PFC which seemed to help the idle quite a bit.

Coulthard Fan

Ok, we are talking about different switches. I'm the one who is screwed up, but of course Mazduh has helped me get to that point. When I called my local dealer, I asked for the "cluch switch" not the "starter interlock" switch" and they looked it up and ordered the part. I get the part (HF05-66-4D0) and it is labeled "clutch switch." Care to guess what it was?

https://www.rx7club.com/forum/attach...&postid=748217

Of course it was the starter interlock switch, so dumbass here replaced the wrong switch, the one at the bottom of the pedal in this photo which is held down by two bolts.

I don't think it is an excuse for stalling either, but I do believe that a lighter flywheel will make the problem more apparent if it already exists since the revs drop so fast when you depress the clutch. Thanks again for your helpful posts.

ronarndt

You may also want to check the refrigerant charge level in your system. If the system is overfilled, the excess fluid causes high pressure and increased resistance whenever the A/C compressor tries to start. This causes drag on the drive belt and slows the engine rpms enough that sometimes it will stall. I had my system checked and a small amount of the over charge removed. Now it's fine.

TailHappy

Oh, man, I'm sorry! I hope I didn't screw up my terminology. I couldn't find any real documentation on it and didn't even really know what I was replacing when I called the dealer. I just knew about where it was and went from there. The one I was talking about apparently is known to wear out. On mine, the spring wasn't popping the switch out anymore, and the PFC verified that it wasn't working. It sure seemed to fix the problem, but again, I put the PFC in at the same time, so it could have been a combination of the two.

Sorry you had to go to all that trouble, but I guess on the bright side it never hurts to replace parts on a 10 year old car!

daem0n

So, what's the right part number? Anybody know?...lol

Coulthard Fan

According to the manual as posted here:

https://www.rx7club.com/forum/showth...threadid=94934

http://www.mazdaformance.com/rx7parts.htm

http://www.abcpages.com/%7Emazda/RX7...%20CHASSIS.pdf

The second "clutch switch" is LA01-66-490A. (Or so it appears from the small print.) The lower switch should be called the "starter interlock" but in the description column it is also called the clutch cut switch . This must be what screwed up my dealer when I called him. Oh well, my bad for not verifying it myself.

ronarndt: My refrigerant level is not the issue. The car stalled before and after I recently filled it up. Thanks for the tip though.

Coulthard Fan

I checked the upper "clutch switch" out this morning by repeatedly depressing the clutch pedal with my hand while I watched the switch. Each time the little pin in the switch did pop out as the clutch was depressed, as it is intended to do. It only comes out about a centimeter, but it does come out every time.

So it looks normal AFAIK, but does this sound normal to you guys? Meaning, can the switch still fail even of it is not stuck in the closed position? Or is it supposed to stick out further when the clutch is depressed?

TailHappy

Yup, it sounds broken. If you push your clutch in and pull on the switch, it should pop out about half an inch or more. It will only move about less than a quarter of an inch when it's stuck depressed. That sounds exactly like my old one was.

blackscorpio

I have the same problem car stalls when AC is on and the car is in gear. This can be quite unsettling as you roll up to a intersection another car infront of you, depress the clutch, and the car dies going 30 mph with no power breaks (Happened to me a few times).

daem0n

blackscorpio - that is the exact problem, I'm going to get the switch, I'll let you know how it turns out once installed.