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Any slow starting when hot?

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Old 07-07-2005 | 08:39 PM
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Any slow starting when hot?

My 04 8 starts fine when cold but once in a while it takes quite a bit of cranking to start it. Again, should not be a flooding issue because it normally happens when full warmed up. Any one else have this problem? haven't read any threads about it on here.
Old 07-07-2005 | 09:26 PM
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yes. Oil is a huge factor in rotorys. Oil makes the seal between the apex seal and the housing. no oil, no compression. When yous car is cold the oil is thick. which makes a good seal. The hotter your car ets the thinner the oil gets. Thus redusing the compression. There also is some left over gas that has not evaporated yet. Its a very common problem usualy on flodded engines (gas washes the oil away) and on newer engines (apex seals are not fully broke in yet). What you can do is when ever you are going to start the car when it is all ready at operating temperature crank it with the gas pedal fully depressed first. It will cut off the fuel. how many miles do you have? i also think there is a new flash out that helps with that problem.
Old 07-07-2005 | 10:33 PM
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I have this exact problem. When it's dead cold, the car starts up instantly. After the first start of the day though, the car gets hard starts, particularly if the day's hot. I took it into the dealership for an oil change and mentioned the problem and got flashed, but I still have hard starts...maybe even worse than before. I think my battery's still the weak and puny stock one, that might be the next thing I look into, or tell the dealership to look into.
Old 07-07-2005 | 11:02 PM
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Originally Posted by Rival
What you can do is when ever you are going to start the car when it is all ready at operating temperature crank it with the gas pedal fully depressed first.
doesnt the manual say to NOT do that?
Old 07-07-2005 | 11:31 PM
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ohh maybe im wrong ill have to check that. i thought that choked the fuel. And a slow cranking battery makes rotarys extremly hard to start
Old 07-08-2005 | 12:18 AM
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Originally Posted by Rival
ohh maybe im wrong ill have to check that. i thought that choked the fuel. And a slow cranking battery makes rotarys extremly hard to start
page 5-4 of the '05 manual

"Whether the engine is cold or warm, it should be started without use of the accelerator"

My guess is it could lead to flooding (fuel injected cars dont like the gas being used to start as far as i know)

Old 07-08-2005 | 08:41 AM
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Originally Posted by Frostee
page 5-4 of the '05 manual

"Whether the engine is cold or warm, it should be started without use of the accelerator"
Yes, but on the RX8 product update DVD, they give an example of how to start a flooded car--by depressing the accelerator fully to the floor, and cranking for 7-8secs (no longer than 10). Release the accelerator, and turn it over again.

My guess in the descrepenacy between the two, is that the MSP04 updated flash possibly added the "cuts the fuel pump with the accelerator is depressed", not present before. I do believe in the TSB's they gave a different technique to the mechanics to cut the fuel pump, and it involved unplugging wires. I assume this new deal was for consumers not to have to pop the hood at all.
Old 07-08-2005 | 09:07 AM
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yeah i thought that mazda had learned from there mistake. To cut the fuel on the s4 rx7s you has to pull a fuse under the hood. When they designed the s5 rx7 they programed it if the pedal was fully depressed it would cut the fuel.
Old 07-08-2005 | 09:07 AM
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I have hard starting if I drive it somewhat and don't give it time to cool down enough before I start it again. Next time I go to start it, it will crank about 3x as long before it starts.
Old 07-08-2005 | 09:11 AM
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how many miles do you have on the car??
Old 07-08-2005 | 12:46 PM
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i have problems with starting it in hot weather as well... Well it always fires up, but i've had to crank it as long as 7 - 8 seconds!
Old 07-08-2005 | 12:51 PM
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time it next time with a stop watch
Old 07-09-2005 | 11:35 AM
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hard starts on cars with M or later pcm level should have a compression test done and have the plugs checked

Using WDS, perform compression test. Print or copy compression test
results.
3. Document all DTCs and Freeze Frame Data.
4. Note condition of spark plug condition. (Example- normal, excessive
carbon build up, fuel flooded etc...)
5. Contact the National Technical Assistance Hotline for more
information.
Old 07-10-2005 | 08:25 PM
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Try this:

Put the key in and turn it to the ON position, but not START. Wait for 3-4 seconds, until the "mazda rx8" logo comes on the display screen, then start it. Ever since I did this, my dragging/hard warm starts have been cut down by 99.9 percent.
Old 07-10-2005 | 09:01 PM
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heheh "initializing" i coined that word for that action ^^
Old 07-10-2005 | 10:17 PM
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Originally Posted by max5roadster
Try this:

Put the key in and turn it to the ON position, but not START. Wait for 3-4 seconds, until the "mazda rx8" logo comes on the display screen, then start it. Ever since I did this, my dragging/hard warm starts have been cut down by 99.9 percent.
Yes this does seem to help with the hard starts...I count to about 20 myself before firing it up. It's just sometimes, somebody else gets into the car with you, and then they see you just turn the key to ON and just sit there waiting and they look at you like you're wierd... :o
Old 07-10-2005 | 11:24 PM
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Originally Posted by scottmhr1
My 04 8 starts fine when cold but once in a while it takes quite a bit of cranking to start it. Again, should not be a flooding issue because it normally happens when full warmed up. Any one else have this problem? haven't read any threads about it on here.
Yup... never had a cold start problem, but it occasionally takes much longer than usual to fire up when it's hot. Scared the heck outa me the first few times (oh no! it's flooded and not gonna start!). Now I'm used to it.

And yes, I *always* wait awhile to let the fuel pump prime itself before cranking it over.
Old 07-11-2005 | 01:38 PM
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I have experienced this. From cold (even very cold), the engine starts after two or three cranks, but it took more like fifteen or twenty cranks after a highway run with ambient air temps in the low 90s. It started, thank goodness.
Old 07-11-2005 | 07:06 PM
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I had the same hard starts when engine was hot. The first time, the dealer did a reflash (not the usual ones, like P or R) - did not help. Next time I went, they changed the battery and installed updated spark plugs. Problem solved (they said old spark plugs were OK at 16000). I think that the culprit is the weak stock battery. When it is hot, it just doesn't have enough amps to crank. This is also in line with the above procedure of waiting before energizing and starting the car....
Old 07-13-2005 | 12:14 AM
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I have had this problem lately. First thing in the morning it will usually start right up. But going out for lunch, or making a series of stops after driving around, it doesn't want to start up. It will crank for a good 5 seconds or so before starting. Or, I'll crank for 5 seconds with no results, think it's really flooded this time, and then on the second attempt it starts right up. I'll try the "insert key, wait a few seconds, then crank" thing tomorrow and report back.

I suspect that it's mainly just a small battery, almost 2 years old, exposed to loads of heat. I think I'll probably replace it next spring whether it needs it or not. If I tell my dealer about it, they'll no doubt tell me it's due to lost compression caused by synthetic oil eating up the seals. (They actually did tell me synthetic oil would damage seals and lower compression)
Old 07-13-2005 | 08:39 AM
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My car is in the shop for failure to start when hot. It dosn't seem to be a flooding issue. The de-flood routine failed to work. The car sputters sometimes but will not start. With a push start, the car fires up.
Old 07-13-2005 | 09:21 AM
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Originally Posted by zoom44
hard starts on cars with M or later pcm level should have a compression test done and have the plugs checked
My car is new (around 250 miles) and is supposed to be on the latest flash - I asked the dealer to flash it before I picked it up.

The car has a build date of 08/2004, so it has been sitting on the lot close to a year.

No problems starting normally, but the battery "seems" weak.

I drove home from work yesterday but made a stop close to the house. I was away from the car for 45 minutes or so and when I came back it spun 20 seconds at seemed to be a slow speed before it fired. Ran fine once it was fired. This morning after sitting overnight it fired much faster. So it is not the charging system and shouldn't be the flash (assuming the dealer did it) - sounds like I just have the weak battery?

I guess I could try to get the larger battery free from the dealer, or just buy an Optima for myself?

Dennis
Old 07-14-2005 | 08:56 AM
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Thanks for the "delay start" tip folks!

I had to run to the DMV yesterday to transfer tags and the car sat for 30 minutes or so - pretty much like the day before on the way home. When I got back in the car I waited after key on but before start - and bingo it fired up MUCH easier.

I still think my battery is weak, but I will need to use less of its (limited?) capacity by delaying the start when the engine is hot.

Thanks again!
Dennis
Old 07-14-2005 | 07:29 PM
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Is anybody using a super-capacitor to take the high demand loads of the stock battery?
Just curious....
Old 07-14-2005 | 09:31 PM
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Today, mine started almost instantaneously as I turned the key. My first thought was, "that's odd" :D


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