car stall at complete stop
 

info: 2004 rx8
miles: 109,000
all stocks

whats been done:
1. change ignition coils
2. change spark plugs
3. clean fuel pump according to the DIY posted in here
4. Seafoam according to DIY posted in here
5. New air filter
6. Oil change
7. Clean throttle body
8. Clean MAF
9. change 02 sensor

***i am catless, my cat burn out awhile back and I took it apart and completely removed all the jump in there. So no cat, just a straight through now.

symtoms: CEL light on
My car starts fine in the morning and idles normal when the car is still cold. When car warms up it idle ok too but after I drive it on the highway for 10 to 15 mins and come to a complete stop, the car will idle up and down like its gasping for air and then the car will stall, when it stall i cannot start it back up. I usually have to wait 30 to 40 mins and let the car cool down before i can restart it.

I just took it to a Mazda Dealer and they found I needed a cat (I already knew that) and misfires from ignition coils and bad spark plugs (hence I changed out the ignition coils and spark plugs this morning) but still same issue. The dealer did not find anything major with the car. BTW...do not do a compression test. When I drive the car on the highway, everything is running normal as expected, only when I come to a complete stop when idle is not steady and it stalls. I've done a lots of researched here and done everything many of you recommended. I've done everything that I know I can do to this car but the issue is not going away, I am pretty much stuck. I am ready to trash the car.
I would really appreciate it if someone can help.

btw...i have not clean the secondary shut valve yet. The dealer did not detect a fail code for it.

This is all i can think of right now, if i thought of something i will be sure to post add it. Thank you in advance.

Please HELP!

what were the actual codes that the dealer gave you? Those will help our diagnosis.

Also, just because you drive fine on the highway, that does not mean that you can't be suffering from low compression...

And what is the code(s)?

Which is one of the first things I would recommend doing.

Wouldn't rule out SSV since the very first stuck SSV I worked on was causing the car to stall everytime he stopped.
Though this can easily be ruled-out.

Also, good to note where you're located in case there are local members who can assist you.

RX8Soldier - The dealer did not give me any codes. I was wondering about that too but forgot to asked for it. I will give them a call tomorrow and see if i can get the codes from them.

Jon316G - No did not do the compression test. If it's a compression issue, would that mean I basically need a new engine and would the compression issue cause the car to stall?

How would I test and rule out the SSV?

BTW...I am in the Tulsa, Oklahoma area. If anyone is around here and willing to help. I am willing to drive to where you at. I need help.

ssv thread https://www.rx8club.com/series-i-do-yourself-forum-73/diy-remove-ssv-beta-teaser-video-184663/

Yes, low compression can cause your car to stall

GTX- Take the car up to Autozone and have them pull the code... its free.

Jon316G - I took the car to autozone before I took it to the mazda dealer. Autozone pulled a code for bad 02 sensor thats why i replaced the 02.

RX8Soldier I will go through that thread and get back to you.
BTW...how much is a compression test???

when did you do all of this maintenance, btw?

Compression test, depending where you're located, can cost between $1-200

The ignition coils and spark plugs was done today this morning. All the other maintenance was done a wk ago.

Any other suggestions???

ok, try disconnecting the battery for 20 min (this will reset the ECU)
Also, try cleaning your eccentric shaft sensor https://www.rx8club.com/series-i-tech-garage-22/tired-searching-ess-cleaning-206687/
Once you finish cleaning the ess, turn the acc on (don't turn car on), pump the brake pedal at least 20 times in 8 seconds (make sure the oil gauge sweeps), then turn car on.

Your car may be relearning the fuel trims. You'll need to do a few drive cycles before your car stabilizes itself. If after a few days, the problem does not correct itself, then you most likely have low compression.

RX8Soldier - Sorry I been away. Will do as suggested by you and will report back to you. Thank you for all the help.

Jon316G - i decided to follow your DIY to clean the ssv. I got everything taken apart except the ssv itself, i got it half inch out but it will not come out complete, it feel like something is stuck. I've spent an hour just trying to get the ssv itself out. Is there a certain way that that thing has to come out? Please help

It just pulls straight out, there is nothing other than gunk holding it.

OK guys - I was able to pulled the ssv out and cleaned it. Wow! very dirty. I hope this is what's causing my issue. Anyway, I got it cleaned and installed. I will take it out tomorrow and run some test on it. BTW...I did not replace the gaskets, I used the old ones, will I run into any leaking issues?

UPDATE: Guys, I took the car out for a couple of test runs this morning and it still feels the same but the car did not stall on me. I let it idle for about 10 mins after the run and it did not stall but did notice the rpm still goes up and down and dip below to the 50 percent mark. I am not convince this resolve my issue. My next and last thing is to do a compression test. I'll wait for a couple of days to test run the car before the compression test.

I read somewhere on another thread that its possible issue may be related to ssv solenoid, I am not sure exactly the name of the part but something to do with the solenoid. If someone can point me to the link or how to locate and test or clean or replace. Thanks in advance.

You need the "updated" kit from Mazda to completely solve this issue. it includes a "holy mightly" stronger spring, longer bolt, gasket and other useless stuff.

it's a "200" something bux "fix", if you don't want to clean your SSV every year or so, this might be your solution.

Have you done the ESS profile reset yet?
The 20 brake pedal stomp thing?

Also, have you checked for vacuum leaks?

Is your car an auto or manual? Is it possible its the neutral switch in the transmission causing the rpm hunting?

One last question:

What do you mean by

50% of what?
Do you mean the engine is revving all the way up to 4500 rpms?

BC.

UPDATE: Ok, so I took the car out today and the car did not stall on me when I come to a complete stop. At one point, i turn the car off and came back in in 15 mins and the car will not start. I let it sit for couple of hours and i was able to start it up and drove home. When I got home, I turn the car off and restart and it restarted right back up. I am completely stump now. I seem to got rid of the stalling issue but the car will not want to start back up. When it will not start, it sounds like I am not getting enough fuels in. Is it possible that the fuel pump is weak when it gets hot??? The car will start and run normal when it has been sitting there for couple of hours. ONly having the start up problem when the car is driven on the highway for a while (15 to 20 mins.).

Is it possible the fuel needs to be replace?
How often these fuel pumps goes bad?

BTW...Does any here has a fuel pump for sale if i need it?

Not sure if you solved this problem or not yet but it sounds EXACTLY like what was happening to my car. Get a compression test. I did and mazda ended up replacing my engine (luckily under the last couple months of my warranty). It sounds like a compression issue, my car used to work fine unless i drove it hard for about 10 mins. Then when it idled, the rpms would fluctuate near 500 rpms until giving out. When it didn't stall, i wouldn't be able to start my car up at times. The times that it did catch, I would have to gas it hard to get the engine started.

GTX, did you ever get this issue resolved? My car just started doing same thing, stalling at red light after driving on highway for some time.

My thought was alternator because this morning when I went to start it after letting it sit for over a week, the starter motor ran slower than usual. I have maybe a 1.5 year old Optima battery so this is unusual. When it stalled today I got CEL and check battery lights, but CEL doesn't remain on when it's running, so I don't think there's a code to check.

Codes are typically stored in memory.
Only way you're going to find out is to have a scanner attached to see what's in memory.

BC.

I got home tonight and checked for codes. Nothing. I poked around a little bit and discovered the intake pipe which connects my Racing Beat intake box to the manifold had disconnected!!! :shocking: That means I've been sucking in unfiltered air for at least 60 miles! Oh well... I reconnected it and idle settled back to normal.