Car stalls after 10 minutes of driving
 

Hey, I have the plaguing issue with my rx7 that is frustrating me a ton!

I have searched on this forum and was unable to locate the same issue as mine, but im certain someone else has had this issue as well. If you know of a thread with the same issue post a link please!

First off it is a 94 RHD Mazda RX7 with 70,000 kms. Car is basically stock with a few minor mods like intake, high flow cat, and boost gauge. (fresh oil change, new thermostat and new fuel filter.)

Ok. So the car starts up great, i let it warm up for like 30 secs to 1 minute before I start driving. Car pulls great, perfect boost, and works like a dream... but after about 10 minutes or so the vehicle seems to just stall. I wont be under acceleration, deceleration, or anything just cruising at 90km/h and she just loses power and I roll to a stop.

When on the side of the road it fires right back up immediately and I can drive for approximately 30 seconds to 1 minute before it happens again! Again, I can fire it up right away but again 30 seconds it will do it again.

I generally let it sit on the side of the road for about 5-10 minutes and I am able to drive up to 5-10 minutes before I have the issue again.

The most frustrating part is that it does not do this all of the time, some days I am able to drive 40 + minutes and never have a blink of an issue.

I started with replacing the fuel filter, but that had no effect on the issue. I then replaced the Thermostat but again had no success.

I am trying to avoid throwing parts at the vehicle because that can get expensive and it can take a long list before you solve your issue. So I am asking for help to see if anyone else has heard of this issue before, or can anyone help limit my search down?

I initially was thinking this is a coolant related issue but I am unsure. Would there be a sensor in the coolant system that is telling my car to turn off because it is too hot?

Is it possible my fuel pump shuts off when it is overworked? but my car fires right back up without hesitation so which makes me believe there is no shortage of fuel in the lines from the pump in the trunk to engine up front.

Is it possible I have a bad coil that misfires when hot but when cooled down operates normally? The plugs are in great condition, i took them out to run a compression test in the fall, compression is great as well.

When the car stalls while driving it does not seem to spit and cough and run rough, im just cruising then all of a sudden, no power and I cruise to a stop. I have the ability to jump start it while rolling but like I said earlier it will just cut out again in about 30 seconds to 1 minute. The only thing that seems to fix it is letting it sit for an extended period and let it cool down.

As I said earlier, mysteriously I can go for a 30-40 minute cruise and never have a blink of an issue.

Any information at all would be a great help!! Thanks in advance!!

When the car shuts down, does all power completely turn off? Radio, lights, etc? Sounds like a bad battery terminal connection or alternator problem.

Possibly the sock on the end of the fuel pump is clogging from tank debris? Had a very similar issue in a friends fb. They have an inline fuel filter that kept getting clogged. Would run great for maybe half hour or so, then just die. After it happens and you restart, does it seem to be ok for the minute or so until it dies again, or is it slow to rev up, etc?

1st guess would be fuel pump loosing power. So I'd check all relays, wiring, fuses etc.... associated with it.

Might be a good time to directly wire the fuel pump to the battery and then see if the problem still exist.

(RX007CYM) when the car dies I still have power, my lights work, radio keeps playing. I would rule out battery or alternator because all electrical works and im able to restart the car so battery must be working.

(Rxmfn7) When the car stalls it runs perfectly for the minute until it happens again. I have a new fuel filter on it so cant imagine it clogging but i could be wrong. When the fuel pump would clog on your friends would he slowly lose power and the car spit and cough?

When i lose power it seems to come quite sudden, no hesitation or warning before hand, just all of a sudden no power.

(Fritz Flynn) i have recently done a battery relocation to the trunk so i cant see it being difficult to wire it directly to the battery. What would be the advantage of this?

Thanks alot for your help guys!

Help trouble shoot pump problem vs power to the pump (wire issue) vs relay.
See if pump pulling appropriate power and/or if power to the pump is being lost somewhere.

Had similar issue and my problem was the relay going bad, intermittent open close.


When's the last time you had gas...possible bad gas issue...vapor lock...? Just shooting out things to check

OK. so ive done alot of researching today and I think I have located what the issue is.

Ignition Module/ Control Unit

After talking to a few people at the dealership and researching online it looks like I have the identical symptoms for this failing part. This is what I have found.

"What are the symptoms of defective ignition module?"

A bad ignition module is usually characterized by several frustrating symptoms. A classic example is when the engine will start, but when it gets hot, the ignition module's electrical properties change, cuasing the car to die suddenly, but restart after several minutes of cooling. Some people have reported pouring cold water on the ignition module causes it to start when hot (mearly by cooling rapidly).

My plan is tomorrow to go for a drive until the car stalls, then have an ice pack handy and cool the ignitor down and if this temporarily cures my issue until it heats up again I will have located my issue and will order the part.

A new igniton control module from the dealer runs about $950 but i found some on ebay for $350-$600.

http://www.ebay.com/itm/MAZDA-RX-7-I...ht_1171wt_1833

Would anyone have any advice for another way of testing if the part is faulty? or would anyone know of a better place to order this part at a lower cost? I will update you as soon as I run my "test" lol

Thanks

I'm not sure if the fsm would highlight that part but it might be worth checking. I certainly wouldn't pay that much. I'm sure if you hit up any number of people doing a part out would let that go for $50 or so.

Bump, so what was the issue? Was it indeed the ignition module?

I borrowed an ignition module off of my friends rx7. (he unfortunately has more issues than me) i had the same issue unfortunately but not as bad. I have a friend with a perfectly running car I'm going to borrow his module and update you then. Still driving the car every day an enjoying it very much. Just quits every now an again if I'm driving far :S it's quite annoying

I have a similar problem, but I have traced it to the fuel pump losing power, posted about it today, you can search on my forum name and Fuel System, voltage to the pump. Check it out it might be your problem too, and likely cost less than the igniter.

update:

new igniter and coil pack have solved the problem!

Thanks