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Dead Acceleration Spots

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Old 03-07-2006 | 07:11 PM
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From: Central - New Jersery
Exclamation Dead Acceleration Spots

My car is back at the dealer for the 2nd time. I'm hitting flat spots around 6K RPM's. They replaced a coil originally and said that would fix the problem but a few days after i got it back the problem happened again. This only occurs when the engine is cold though, it seems to run fine and accelerate normal when it is running warm. They have had the car for two days now and are running test to make sure the engine is not losing compression. I am now much more worried. Anyone have any recommendations or thoughts on what is wrong? The 626 i'm currently driving just doesn't do it for me.
Old 03-07-2006 | 07:13 PM
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umm... why are you even taking it up to 6k cold?
Seems a lot of people who have tried to rev while cold have encountered this.
Old 03-07-2006 | 07:24 PM
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I do have a heavy foot and understand I shouldn't, but nonetheless this happens and CEL flashes at me. All that being said and behind, it's still in the shop and having these problems which were actually succesfully reproduced by the tech, believe it or not.
Old 03-08-2006 | 12:56 AM
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From Section 5.4 of the owners manual:

To protect the engine, when the engine coolant temperature is low,
the engine does not run at high speeds. The fuel supply will be cut
at an rpm lower than the red zone.

By design, the ECU is limiting the RPMs until the engine warms up. Redlining a cold rotary is a good way to warp the housings. Take it easy until it warms up or you'll be seeing your dealer a lot.
Old 03-08-2006 | 01:27 AM
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Wile E. Coyote: Being a genius certainly has its advantages. [notices lit fuse, dynamite explodes]
Old 03-08-2006 | 01:41 AM
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my car does the same thing......good accel all the way up then levels out at 6000rpm and kicks back in at 6500rpm. i've heard that this is normal even if the car is warmed up. Some port opens at 6000rpm, that could have something to do with it. I don't think warming up will solve it. It doesn't cut out it kind've peaks at 6k rpms then starts climbing again at 6.5k rpm's.

Last edited by Rich Rx-8; 03-08-2006 at 02:28 AM.
Old 03-08-2006 | 01:56 AM
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you have a nasty hole in your fuel map, ajust the nos timing and you'll run nines. whats this fool sandwich crazy????
Old 03-08-2006 | 02:11 AM
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So it def should not level out at 6000 rpm's then get more accel at 6500 rpm's ??
Old 03-08-2006 | 02:14 AM
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Anyone have an answer? Cause i'm takin mine to the shop if this is abnormal.
Old 03-08-2006 | 05:07 AM
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On a cold engine, the ECU will limit the available RPMS =>REV LIMITER! This is done by design to protect the engine. Think of it as a sandwhich with each slice made of a different metal, some metals expand at different rates when heated. If you continue to do this, your sandwhich will become a leaking pile!!! It is not an engine problem, it is a driver issue.

Rich, the slight hesitation or fall off at around 6k is normal, assuming accerlation increases/ resumes afterward. You are experiencing the ports operating. When my car was newer, this operation seemed to be more abrupt, but has since mellowed out. Please, try to understand that a rotary is not like a conventional engine. Seach this board and the rx7club to help you learn more, then you'll be able to relax and enjoy your car more.
Old 03-08-2006 | 07:04 PM
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Thanks for all your helpful criticism..., dealer found that the ignition coils were fowled and is replacing them.
Old 03-08-2006 | 08:29 PM
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If you can rev past 6k on a cold engine (which you should never do) then there is something wrong. Coils not withstanding, your car will behave this way when it is cold.
Old 03-08-2006 | 08:39 PM
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Thanks Max, you stated the obvious, which is a trend around this forum, but still your input is appreciated.

Last edited by Rich Rx-8; 03-08-2006 at 08:44 PM.
Old 03-08-2006 | 08:42 PM
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Basically I've properly warmed up my car everyday that I've turned the key without fail since I bought last June and I dont put the car in reverse to back out of my driveway till the temp is halfway.

Last edited by Rich Rx-8; 03-08-2006 at 08:46 PM.
Old 03-08-2006 | 09:21 PM
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Just tryin to help...shrug... dunno? Did your 8 do this since new? 04 or 05? Have you had the thermal recall/lastest flash? From your prevoius posts it was unclear if your car was warmed up or cold. You could take it in for peace of mind. I don't think from your description that anything is wrong, but I can only offer you my experience up to this point. Maybe you have a sticky port..?..?..

BTW, iuf everything here were as obvious as we both think it should be then we wouldn't have 2-3 current "car won't rev past 6k cold" threads, or "my oil is milky", or... well you know what I mean.
Old 03-09-2006 | 06:33 AM
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The temp needle being halfway means nothing... you can drive the car almost immediately when the rpm gets down to 1.5k then dont exceed 4krpm.
Rich, have you totaly been warming the car up before booting it?? you need at least 10 minutes of driving to propely warm all the fluids up in the engine and gearbox etc.
Old 03-09-2006 | 04:41 PM
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I'm sorry, but I think some people are being really REALLY prude about the engine temps. The engine is fine to run cold...you don't need to let it sit in your driveway for 10 freaking minutes before going anywhere.

I drive my car daily 30 seconds after I turn the key. I also give very light gas if the engine is cold, accelerate very slowly early on, and don't rev over 3500 or so. The car will be sluggish and unresponsive when it's really cold. Listen to her She'll tell you when it's ok to really drive. Am I the only one that feels the 8 talk based on engine temps? It seems pretty intuitive to me...
Old 03-09-2006 | 08:53 PM
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Yeah the whole Rev Limiter thing is kind've obvious and I don't think that it causes the hesitation at 6k rpm's when the car is warm. I've noticed hesitation at 6k even when fully warmed and driven for quite a while. And you were also telling us that this car has a rotary engine and that we should use search, which is coo, i just think it's funny. Thanks for your info anyway, I had a feeling and already said that it was the ports opening, I just wanted to know if the hesitation was normal.
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