Wayne in Plano

...thought I might check with my Gulf guys first...

I had a couple of starting issues come up. When I started the car a couple of time last Sunday, it would start, immediately rev up slightly, drop down, then die. It might do this a couple of times, but eventually did start, rev smoothly and drive OK. Then later on that evening I went to go to the grocery store - it started fine, but on the way once when I went to accelerate, nothing happened, no increased rev's etc. - only happened once, then after idling a little more ran fine again. Left grocery store, started fine, seemed to be driving fine, but then kind of shuddered and again no acceleration. Pulled over shut it down, waited, then could not get it to start at all.
After a full day at TNM (Town North Mazda) they said they couldn't figure it out. Then late Tuesday they came back and told me it appeared to be the gas tank sensor/relay was reading incorrectly and car was basically out of gas even though gauge showed over 1/4 full. (must have been something new as I had on other occasions driven it to less gas showing on the gauge)
After de-flooding, and new coils, new plugs, new battery etc. (including filling gas tank) picked it up and drove home fine yesterday. This afternoon it died twice again just after starting.
Obvioulsy I'll be calling Penny at TNM again Monday, but thought I might thow it out to you guys to see if you had any ideas....

Riley Craven

iTrader: (1)

I could be WAYYYY off in this, but do you know if they did a compression test on your engine?

I'm not sure I believe that gass sensor thing. If it was the gas sensor logic would follow that if the car was out of gass it would never start.

But I'm not a car expert by any means.

Wayne in Plano

Yes, while it was in I had them do the 30K mi service (car only has 29Kmi)
Per Penny compression was 7 (?) across the board which she said was better than normal (?)

Haven't tried to start it yet today...we'll see

WTBRotary!

iTrader: (6)

Im not too sure on this one...

JoeHawk

iTrader: (1)

Hey Wayne. Any updates? I'm taking mine in to Penny tomorrow for starting issues as well. Nothing as severe as yours, but aggravating just the same. Mine just doesn't like to start very quickly after it's warmed up.

Wayne in Plano

After driving it Sunday and again today - it seems like mine is doing the same as yours. Both mornings it started up right away (it rev'd a little high initially - 2000rpm and then would drop after a few seconds. But then after driving it and letting it sit for a time 15min - hour + or so - it would turn over, start but RPMs would immediately drop to under 500 or so and stop. it might do this a couple of times before i could get it to start and run for a couple of seconds and then it would even out and run fine.

I haven't called Penny back yet, (weather was too lousy to run it by today)

Like you said, it's starting but aggravating - and of course I'm paranoid about flooding it....

Interesting to see if we're having the same problem...

Wayne

JoeHawk

iTrader: (1)

Mine hasn't died, it just takes awhile to start. I'd hate to think that mine is just in the initial phase of breakdown and will soon start dying like yours... ugh. I'll let you know what Penny says about mine tomorrow.

JoeHawk

iTrader: (1)

So, she's still at TNorth. After "investigating" all day they determined it was 3 bad coils that was causing the starting issues. I suppose it could be, but I just replaced all 4 coils 5k miles ago. If I have to replace coils every 5k miles, thats going to suck. Not sure what to think at this point. They will test compression tomorrow as well.

Wayne in Plano

...well looks like mine's on it's way back to TNM. Was out running around this afternoon, went by the grocery store just down from the house and it now won't start again....turning over - but not starting. Have a call in to Penny to set up a tow etc.
...this is a real pain...

Charles R. Hill

iTrader: (7)

Compression numbers in the 7s is somewhat weak. Not low enough for major power loss or engine replacement but certainly not better than normal. A little lower and you're getting close to engine replacement time. Coils tend to get weak around 25K-30K miles (or so I have read).

Curing erratic engine operation can often be as simple as an e-shaft profile reset, cleaning of the MAF sensor, coil/spark plug/wire replacement, cleaning the air filter, wiping off the e-shaft sensor...... and some other simple stuff that Jon316G may recall.

JoeHawk

iTrader: (1)

Thanks Charles! Yeah, I talked to Jon316 (GREAT guy)some yesterday after reading his DIY threads. Turns out that the majority of my issues were caused by low compression. After the dealer ran the first compression test the numbers came back in the low/mid 600's. The tech called Mazda, they had him do the zoom-zoom/decarb and replace the plugs. That with the new coils seem to have cured my starting issues. After the decarb they ran another compression test with numbers coming back in the upper 700's. I asked Penny for the actual numbers, hopefully I'll have them tomorrow. If so, I'll post them up. Curious if the new numbers are actually as good as I was told.

But, hey, at least it starts now.... lol

Jon316G

iTrader: (1)

That damn air pump situation still confuses me
Lesson learned... if you have trouble after doing something, put everything back to what it was, even if you don't believe it has anything to do with your issue.

Awesome... glad you got it started!
Upper 700kPa is pretty good compression numbers.
Mazda's spec is 830kPa standard and 680kPa minimum.
If you do get the compression numbers, make sure you get three numbers per rotor (since the rotor has three faces) and the RPM.

JoeHawk

iTrader: (1)

I knew about the three numbers, but wouldn't have guessed to ask about the RPM. I don't see why they wouldn't give me the numbers, but who knows.. lol

I may still try some of your cleaning DIY's - I figure it couldn't hurt, right?

Jon316G

iTrader: (1)

The Mazda specs are for 250RPMs, but if your RPMs are lower, the compression numbers will be lower.
This is why we have to "normalize" the recorded numbers to see if its really within spec.
Here is an example of a compression test I performed on a motor that was pulled out of a wrecked 8:

Note the values I have are in PSI instead of kPa.

Depends... if its something that requires you to remove multiple components, anything could happen if not reinstalled properly.
Example is the SSV... since you need to remove the thermostat housing and hoses, you could experience coolant leaks if the clamps aren't tight or the gasket is damaged.

This is why I stress not to perform some of the tasks unless you're experiencing a problem and know that it will correct the issue.
But if you're like me and just like to take stuff apart to learn/understand better, I'm not going to stop you.
Just be aware of the possibility that you might make it worse and have to tear everything back down again.

xsnipersgox

they are really throwing parts at problem with their standard protocol, if you want i live around 75/190 and we can compare it / swap parts to see if any parts gone bad, record it put on youtube for ppl to see. let me know, jobless so always home.

Charles R. Hill

iTrader: (7)

Have you heard what Kane's numbers were after I built his engine?

Wayne in Plano

OK - after car sat for 2hrs and 45 min went back to give the tow truck operator the keys...and car started right up...still didn't rev smoothly though fluctuating like I had mentioned earlier...so went ahead and had them take it. Can't wait to hear what they find now.
Think when I talk to Penny in the morning I will use some of Charles R. Hill's comments -
"erratic engine operation can often be as simple as an e-shaft profile reset, cleaning of the MAF sensor, coil/spark plug/wire replacement, cleaning the air filter, wiping off the e-shaft sensor..... "
and hear what she says.

When I spoke with Penny at TNM she did mention Rowlettrx8er's new compression numbers were slightly higher than what mine were so will be interested to see what numbers you get back.

Jon316G

iTrader: (1)

No... but I'd be interested to hear about it sometime!

Charles R. Hill

iTrader: (7)

Cranking compression in the high-8s/low-9s, and ceramic apex seals are known for low cranking/idling compression. Yes, I am jealous of that ***** and shoulda kept that engine for my-damned-self.

JoeHawk

iTrader: (1)

Here are my numbers..

Before decarb:
Rotor 1 670, 710, 690
Rotor 2 670, 690, 670

After decarb:
Rotor 1 730, 760, 750
Rotor 2 760, 750, 760

RPM=250

Riley Craven

iTrader: (1)

Could the decarb thing be not driving your car hard enough? I was under the impression that carb buildup shouldn't be an issue with a redline...

Maybe Charles, or one of the other posters know more about this and could comment.

J8635621

iTrader: (10)

The redline a day thing isn't a cure-all. It's just supposed to help. There are still some people that say redlining the car isn't necessary and may be too much. Eric Meyer said his cars were set to somewhere in the 8300ish range instead of 9000 I thought.

JoeHawk

iTrader: (1)

I think the prevailing thought on the forums is that it definately helps. But
like j8635621 said, I don't think it totally eliminates it. Apparently, at least according to Penny , the summer mix for gas here in NTX is also a heavy contributer towards carbon buildup. Take that for what its worth...

WTBRotary!

iTrader: (6)

dang joe, I bet you would have loved a new engine before the texas state meet

Wayne in Plano

just heard from Penny...
rimmediately after I picked the car up last Friday, i took it and had a new Optima red top battery installed. TNM is saying changing it caused crank shaft programmin issues. (Is that the e-shaft profile reset Charles R. Hill mentioned ? - told you I'm mechanically challenged). Penny says they've reprogrammed it and everything is fine.
On my way to pick it up later.

I have to admit I've never heard that simply changing a battery would cause "programming issues"...and I'
m somewhat skeptical. Is that another "secret" gem that only applies to rotary engines?