dmorales

I have been having a weird problem.

I can walk out in the morning and start my car, and drive away and everything is normal, but if I drive for more than like 10 minutes then shut the car down, then try to restart the car - it doesn't want to start.

After sitting for a few minutes and a few cranks, it starts. Or if I wait for like 45 min. it starts right up, no problem.

I changed the plugs today, and it runs fine, and started noticeably easier, but still had some problems restarting, but it seems a little better.

Anyone have any ideas?

RIWWP

iTrader: (2)

Trouble with hot starts when cold starts are just fine is low compression nearly every time.

It's possible it's a fuel pump issue, and possible that it's an issue where heat is affecting the coils, but usually it's low compression.

dmorales

low compression as in = very bad...engine not healthy..seals not good?

dmorales

I just noticed a new thread in General Discussion about low compression symptoms.

kingdan2

I had same problem with mine and sure enough it was low compression.

RIWWP

iTrader: (2)

Loss of compression could be any one (or more) of the seals from either rotor, be it side or apex. I personally suspect that the symptoms of compression loss can change based on which seals aren't sealing properly, how the seal isn't sealing, and to what degree. But I have nothing to back that up and so avoid making claims that direction.

They could be not sealing properly for a variety of reasons as well, such as
carbon buildup creating an non-smooth surface
carbon in the seal grooves pushing the seal out of place
the seal has worn down
the seal spring has deformed
the seal has deformed
the seal has broken/cracked
the seal has disintegrated
or
the metal against which the seal pushes has worn or deformed too far for the seal to reach

Metals expand when hot, different metals expanding at different rates. Mazda had to make housings of a material that expanded faster than the rotors, or risk having the rotors start making contact with the housing as the rotor expands, possibly locking the rotor against the housing the same way an axe would get slammed into a tree trunk. So the housings expand faster, which means that seal tolerances and gaps change as the engine heats up. There is an expected amount of expansion gap that the seals are able to bridge when everything is brand new. Over time though, the seals have a harder and harder time bridging this gap, and compression is lost.

Compression is already weak at low RPM, and this just compounds that problem. You can "overcome" it by getting the starter to spin the engine faster or have a much better spark, but the compression loss still exists and will rear it's head again.

dmorales

Thanks so much! I will get a compression check and go from there.

dmorales

Update:

Today, I went to AZ to rent a compression gauge. While I was there I checked the CEL I had got checked last week. Instead of telling me it was an O2 sensor the guy was honest and said he didn't know what it was, but gave me the codes, which I looked up, but wasn't sure.

P0661
VIS Control Solenoid Valve Circuit low input
probable causes:
-Open or Short Circuit Condition
-Poor electrical Connection
-VIS Control Solenoid Fault

While I was there I had my battery checked. I took it out and brought it in. It checked out fine. I put the battery back in.

From then on out, I had a hard time keeping the car running. It started fine. Seemed to level off the RPM's but when I began driving it began to die when I let the RPM's Drop all the way. (ex: coming to a stop)

I got the car home, and I started the compression check.

I have never done one before, so here's what I did. Let me know if I did it correctly.

-Pulled Plugs - Trailing
-Removed Fuel Fuse
-Hooked up tester
-Cranked for about 5 seconds and read gauge

Rotor 1
First Crank - 110
Second Crank - 115
Third Crank - 112

Not sure fi I was supposed to do 3 Cranks, but I wanted to see if it would be consistent.

Rotor 2
60, 45, 40

I am not sure how accurate these are. Tomorrow I think I will test again, but Rotor 2 first, pending what people tell me in this thread.

After I put everything back together I went to test drive around the block. It started up fine, no CEL. I drove it around and as soon as the engine got warm, it started to die again at low RPM's. Then CEL is back on and it won't stay running.

help!?

Brettus

iTrader: (2)

When you took the battery out you reset the pcm . It needs to re-learn idle settings so some stalling out is not unusual till the trims are reset.

In saying that you no.2 rotor is way down . Suggest you do a decarb and then retest .

Also - if you want to avoid a rebuild and get reasonable starting make sure :
coils leads and plugs are good
Battery is strong
Starter motor is fast (upgraded one)

dmorales

I know some stalling is normal, but it won't stay started. I got it to start and idle, but then when I drove it and it heated up it started stalling again.

Not sure what a decarb is? Could you explain?

I had battery tested it's good.
I just replaced spark plugs.
I do have the upgraded starter, but it has been a long long time.
Not 100% on the coils BUT if it were something like that, both would be down right? So there shouldn't be so huge of a difference in compression between the two?

Brettus

iTrader: (2)

po661 is SSV (secondary shutter valve)solenoid - would not affect starting but needs to be addressed nevertheless

dmorales

Thanks, what would one need to do to address the issue? Is this something that needs to be looked into further, or is it a component of some part I can replace?

Brettus

iTrader: (2)

Decarb is the procedure to decarbonise the engine . Do a search for a good DIY on that.
The stalling could be as a result of your poor compression in rotor 2 also.
Coils don't affect compression.

Brettus

iTrader: (2)

Do a visual check of the SSV operation first .
With engine running watch the SSV actuator while someone turns off the ignition. The SSV does a test cycle after the engine is turned off .