Mazda Rotary Club

General => General Technical => Topic started by: framey on March 23, 2005, 11:20:22 AM

Title: Bogging/Popping until 2500 rpm
Post by: framey on March 23, 2005, 11:20:22 AM
Hi,
I\'m writing this in the hope someone will save me having to make the expensive journey over to the UK and it turns out to be something simple.
I have a 3rd gen (92) auto.
When I try and accelerate the car from low revs, it pops, stumbles and generally bogs down until I reach 2500 rpm when everything then seems normal. This happens hot or cold but is worse when warm. Boost seems normal. I have no mods and a standard ecu. I\'ve recently had the engine re-built and although I\'m not sure I had the same problem then, but I may of. If I did, it seems worse now. It has new plugs and recent magnacor leads. Checking under the bonnet everything looks ok, and in any case as the engine has been apart, I\'m sure it has been put together right - vacuum lines etc etc.

Sometime after a longish run, when I restart it it cuts out when pulling away/idling. Maybe something to do with a "cold start" system? It starts ok again after this.

Is there some significance in 2500 rpm?

HELP please!
Thanks
Title: Bogging/Popping until 2500 rpm
Post by: Big Stu on March 23, 2005, 11:41:52 AM
Has the engine been ported at all?? And do you have any mods on the car?
Title: Bogging/Popping until 2500 rpm
Post by: framey on March 23, 2005, 12:27:55 PM
No, no porting and no mods.
Title: Bogging/Popping until 2500 rpm
Post by: gsb876 on March 23, 2005, 12:58:48 PM
Sounds like the ECU needs setting up properly ?
Title: Bogging/Popping until 2500 rpm
Post by: Donato on March 23, 2005, 01:00:51 PM
The ecu might need reset...

There is a procedure for resetting the ecu, cant remember it exactly, i think you have to disconnect the battery and hold down the brake pedal for 20 secs the reconnect the battery....might be wrong though...
Title: Bogging/Popping until 2500 rpm
Post by: Big Stu on March 23, 2005, 01:09:29 PM
http://www.mazdarotaryclub.com/forums/showthread.php?s=&threadid=11925&highlight=ecu+reset

Donato\'s right for the ECU reset.

Might be worth a go
Title: Bogging/Popping until 2500 rpm
Post by: framey on March 23, 2005, 03:53:59 PM
Hiya,
tried resetting the ECU some time ago - I seem to remember it made things better for a few mins.
I\'ll try it again  - just in case.

Anyone else know if 2500 rpm has any signifigance?
Thanks
Title: Bogging/Popping until 2500 rpm
Post by: Ricco_04 on March 23, 2005, 05:08:12 PM
Clueless person responding...... :rolleyes:

Isnt 2,500rpm about the time that the first tubby comes online?
Title: Bogging/Popping until 2500 rpm
Post by: Shark on March 23, 2005, 07:54:12 PM
first tubby is spooling from the start and should be up to full boost between 2 and 2.5krpm.

2,500 rpm is roughly when the airpump kicks in.  You could just unplug it to see if it makes a difference but I can\'t see how it would.  
:confused:
Title: Bogging/Popping until 2500 rpm
Post by: saxon on March 25, 2005, 08:29:10 PM
funny! i have a 92 auto with no mods, apart from no cat exhaust and mine keeps doing the same thing from 1500 to about 2200 then clears. its been driving me nuts now for months, has cost me £600 with no improvement. been told it could be the idle control valve now, here we go again!!!
Title: Bogging/Popping until 2500 rpm
Post by: clive on March 26, 2005, 09:27:47 AM
Hiya,

Does the engine idle properly ?

If it\'s flutuating it could a vacum pipe, have a special look at the Map sensor.

The other one is, check that you have the injector wireing clips are on the right way round and that you havent got the primarys on the secondarys and vice versa.
Title: Bogging/Popping until 2500 rpm
Post by: saxon on March 26, 2005, 01:44:01 PM
hi,
the car idle varies but not constantly. one day it will be at 900, then the next 11 or 12. also while it is stuttering smoke pours out of the exhaust. If you feather the throttle it eventually goes. it never does this above 2000 to 2200 rpm. thanks for your help.
Title: Bogging/Popping until 2500 rpm
Post by: TonyBlair on April 03, 2005, 09:15:14 PM
Saxon, did you resolve the problem with your car?

The problem you\'ve described sounds similar to the problem I had; the bearings on the primary turbo were knackered. At idle it smoked, under load the smoke cleared.

Have you thought about getting it to a local specialist?

Cheers
Jon
Title: Bogging/Popping until 2500 rpm
Post by: saxon on April 06, 2005, 09:48:13 PM
has been to one and cost me quite a sum but to no avail. will hv to go again soon, when money allows!!!
Title: Bogging/Popping until 2500 rpm
Post by: scooby_si on April 07, 2005, 07:13:30 AM
who did you go to?
Si
Title: Bogging/Popping until 2500 rpm
Post by: saxon on April 07, 2005, 07:15:47 PM
far east in radlett, herts. they were ok but they had it twice, charged me twice and didnt sort it so i wont be back!!
Title: Bogging/Popping until 2500 rpm
Post by: Warthog on April 07, 2005, 07:58:33 PM
I live the top end of Northamptonshire and i go to Geff at Reworx in Portsmouth. I know if i have a problem it\'s sorted, no returns. We all suffer from trying to get our FD\'s right and it does take time as a lot  are up to 10 yrs + old. The choice of where to go is up to you, check out the company reviews on this site and FDUK, then make an informed choice. Don\'t rush in to get it done asap. You may well have to travel some miles to a good RX-7 garage as they are few and far between, so do your research and you will not be putting your hand in your pocket for no return. Good hunting. :wave :wave :wave
Title: Bogging/Popping until 2500 rpm
Post by: framey on April 13, 2005, 04:33:45 PM
Hi,
Been told that my “Knock” sensor is goosed. Would this have anything to do with my problem?

Where can I get a new one â€" Mazda? Anyone have any idea how much these run to?

Can someone tell me where it is? A diagram would be peachy!

Thanks
Title: Bogging/Popping until 2500 rpm
Post by: nikp on April 14, 2005, 02:12:45 PM
If your knock sensor is screwed, i would not drive your car any longer. Rotaries do not like knock at all - not even for a fraction of a second. A knocking rotary is likely to throw an apex seal, and require a rebuild.