MSM gurus, report to this thread, ........ Please :) brain teaser inside

[ZQQMIN]

ok, when i purchased the car its had the current issue of bogging down after a rev . which i was told had always been like that and then was told "how to drive it" when coming to a stop you have to follow the car down to 1000 rpm before depressing the clutch, or it will bog down and back up a few times and possibly shut off, if it doesn't shut down it will then find its natural idle.

this cannot be normal, and after I'm thinking MAF. i checked codes and guess what MAF was one, so i reset and it popped up later but ONLY after gettin into it from a stand still puttin the shifter through the gate, 1st through 3, a loud , POP POP POP POP ... then engine light. BUT letting out of it it ran normal .

checked the CEL and it was the MAF . i didnt reset it , but it did itself after being cycled a few times. as wierd as it may sound i dont like it at all BUT ive gotten used to it and didnt want to replace it for a few reasons . Im not 100% sure its bad , as it corrected itself, maybe it just cant read that amount of air blasting through it under hard acceleration, and the fact i may go to MAF delete once i learn more.

BUT , here more recent.. the reason for finally just sitting here and typing this all out is due to whats also going on now in conjunction with the bog down issue. just to be clear .. ( both these problems happen no matter whether cold or operating temps)

now, to the issue: if sitting still it idles fine, but once clutch is depressed ( still idling normal) once placed into gear , ANY gear 1-6 or R. it revs up approx 400 rpm all by itself,

if you go back to N, idle comes back down...now that i have a coupound problem i figured id rack some of the GURU's brains, there seems to be quite a few guys here that know their stuff.

( i was one of those guys on the SE-R forums ;) ) anyways , ANY and all help is appreciated , so i thank you in advance for your input!!!

[—atank—]

Is your throttle body inlet tube and diverter valve (BOV) stock?????, if so then they both need to be replaced, the OEM units are rubber and plastic and they both leak. I would say that the "POP POP POP POP" is you hitting the stock rev limiter, its set at 6700 rpm.

[SM16RMSM]

I do recommend replacing them but that won't cause his issue. I won't be able pin point the issue but I can point you in a direction that could lead to fixing the issue. To me, it sound like the typical BOG symptom that is related to all MSM. When you leave a light, does it just bog and doesn't want to go? Another item to look at is to see if the MAF sensor is dirty. You can buy a can of MAF cleaner and spray the sensor down.

P.S. A video will help show what it is doing.

[—atank—]

The bog is caused by a sticking 3-way solenoid valve. See:
http://www.mazda-speed.com/forum2/in...ic,9885.0.html

For more than you'll care to read about the subject:
http://www.mazda-speed.com/forum2/in...c,14858.0.html

[ZQQMIN]

Is your throttle body inlet tube and diverter valve (BOV) stock?????, if so then they both need to be replaced, the OEM units are rubber and plastic and they both leak. I would say that the "POP POP POP POP" is you hitting the stock rev limiter, its set at 6700 rpm. No Sir , they arent , nothing is stock , other than the block and that has Carillo rods, new bearings and rings about 40,000 miles ago. ... all polished aluminum tube , Turbonetics T3/T4 turbo, 57 trim, HKS SSQ blow-off Valve, Tial wastegate- 38mm
and the POP POP POP POP, HAS A SPLIT SECOND BETWEEN EACH "POP" rev limiter , is a quick "pop" or "rev" (sounds more like , yen,yen,yen,yen on the limiter)


I do recommend replacing them but that won't cause his issue. I won't be able pin point the issue but I can point you in a direction that could lead to fixing the issue. To me, it sound like the typical BOG symptom that is related to all MSM. When you leave a light, does it just bog and doesn't want to go? Another item to look at is to see if the MAF sensor is dirty. You can buy a can of MAF cleaner and spray the sensor down. it will leave the light fine , provided you understand the way a manuaql vehicle works. no bogs or bucking, it has good power, its just .... say your at 3 grand cruising, and u need to come to a immediate stop you press the clutch and brake, or even if you were to just press in the clutch , it will bog down , and possibly die UNLESS you follow it down IN GEAR to 1000rpm.. i was planning on cleaning it , but i havent done so yet, any particular brand cleaner u recommend ?

P.S. A video will help show what it is doing. good idea and i will certainly see if i can make that happen... Thanks Guys !!!

[ZQQMIN]

atank... thanks for the link , but all i get when i click on either .... Not Found

The requested URL /forum2/in...c,14858.0.html was not found on this server.
Apache/2.2.3 (Red Hat) Server at www.mazda-speed.com Port 80

[bigx5murf]

clean bog solenoid

[SM16RMSM]

it will leave the light fine , provided you understand the way a manual vehicle works. no bogs or bucking, it has good power, its just .... say your at 3 grand cruising, and u need to come to a immediate stop you press the clutch and brake, or even if you were to just press in the clutch , it will bog down , and possibly die UNLESS you follow it down IN GEAR to 1000rpm.. i was planning on cleaning it , but i haven't done so yet, any particular brand cleaner u recommend ?

No Sir , they arent , nothing is stock , other than the block and that has Carillo rods, new bearings and rings about 40,000 miles ago. ... all polished aluminum tube , Turbonetics T3/T4 turbo, 57 trim, HKS SSQ blow-off Valve, Tial wastegate- 38mm
and the POP POP POP POP, HAS A SPLIT SECOND BETWEEN EACH "POP" rev limiter , is a quick "pop" or "rev" (sounds more like , yen,yen,yen,yen on the limiter)

Saying if I know the way a manual works is a understatement. I race Miatas and I have a MSM for a daily driver, one has a 5-speed and the MSM has the 6-speed version. Are you running a stock ECU by any chance? Any piggyback system or fuel management at all? How much boost are you running? Stock MAF can only handle something like 14 or 15 PSI before the are unable to read and/or damaged. Also, if your running the stock ECU, the ECU can't handle the changes that have been made and it most likely the point of the issue. It might even be that it getting to much fuel and that is causing it to have the pop pop sounds. like it backfiring. As for MAF cleaner, I recommend CRC MAF Cleaner. That is what I use.

[bigx5murf]

What kind of fuel mgmt?

[ZQQMIN]

Saying if I know the way a manual works is a understatement. I race Miatas and I have a MSM for a daily driver, one has a 5-speed and the MSM has the 6-speed version.( TRUE , maybe i wasnt as clear, i dont know if wording it as ... the "FUNDAMENTALS" or "DYNAMICS" of how a manual / stick shift work. or maybe letting MRN(Mazda Roadster.Net) know that ive been driving/ riding vehicles with clutches since i was 5, however you not knowing me , i do see your point.). Are you running a stock ECU by any chance? yes i am. I cant decide if i should just go Hydra or back tio the Apexi piggy back fuel mgmnt/ Boost cntrlr. or any other piggy back for that matter. Any piggyback system or fuel management at all? No, not since ive had it , BUT it did have the Apexi safc and theAVC-R, but those have been removed before i purchased it so i dont know how it ran WITH them How much boost are you running? about 7psiStock MAF can only handle something like 14 or 15 PSI before the are unable to read and/or damaged. Also, if your running the stock ECU, the ECU can't handle the changes that have been made and it most likely the point of the issue. this is definatly a concern and and the part the reason im thinking about puttin the apexi stuff back in , that and the fact that the sub harness for them still seems to be in tact. It might even be that it getting to much fuel and that is causing it to have the pop pop sounds. like it backfiring. it does sound like backfiring BUT from the engine bay not the exhaust. I WILL say from time to time i DO get a "POP" from the exhaust from time to time, just going through the gears, normal driving NOT getting into it. doesnt seem to be an issue however id like to know if im shooting a flame ( i cant tell from the drivers seat) As for MAF cleaner, I recommend CRC MAF Cleaner. That is what I use.

i use CRC products all the time, "lectromotive" contact cleaner, "BRAKLEEN" , "carburetor cleaner", etc. i dont think ive EVER come across thier MAF cleaner. ill look into that tomm. after i send the guys to lunch.. Hey , just so you guys/girls know i appreciate the time taken to help another out . so again , i say THANKS...

[ZQQMIN]

What kind of fuel mgmt?

STOCK ECU , at the moment.... read above in Blue. I hope that is easy to understand we use that method at work , so you can get an idea of whats being answered without constantly scrolling, it also helps me as i can answer each individual question as its easy to read , its right there, not having to try to remember exactly the way it was worded ect.

[bigx5murf]

STOCK ECU , at the moment.... read above in Blue. I hope that is easy to understand we use that method at work , so you can get an idea of whats being answered without constantly scrolling, it also helps me as i can answer each individual question as its easy to read , its right there, not having to try to remember exactly the way it was worded ect.

well symptoms sound like either the infamous BOG, or a vacuum leak

[ZQQMIN]

YEA, im working on replacing all (or most of ) the vacuum lines as that was the first thing i was thinking. i found one that seemed brittle and was reason to start counting linear feet and diameter... the infamous BOG im not aware of,.....yet here comes da search !

[SM16RMSM]

( TRUE , maybe i wasnt as clear, i dont know if wording it as ... the "FUNDAMENTALS" or "DYNAMICS" of how a manual / stick shift work. or maybe letting MRN(Mazda Roadster.Net) know that ive been driving/ riding vehicles with clutches since i was 5, however you not knowing me , i do see your point.).

No hard feeling. I been driving and racing since I was 11 so I pretty good behind the wheel. You could be just as good too.

yes i am. I cant decide if i should just go Hydra or back tio the Apexi piggy back fuel mgmnt/ Boost cntrlr. or any other piggy back for that matter.

The Hydra is overpriced and not worth it. There is a limited amount of support and it very hard to find a tuner locally for one. You will have to ask a few tuners to see what aftermarket ECU they can tune. Hydra is 95% of the time not on the list. Just in Orlando, I found one shop that can tune a Hydra but they charge extra since it very difficult for tuning. For a good standalone ECU, look into MegaSquirt. Best bang for your buck. bigx5murf can chime in a little about Reverent, he has a custom built MS2 Enhanced unit.

about 7psi

That is under stock boost level. The guy who you bought it from must have backed it down since he took the Apexi units out. These units are pretty much out of date. A Stand Alone ECU like the MegaSquirt can do way more than the Apexi units. The Apexi Safc tricked the ECU to bump the fuel curve up with the increase amount of air. The Apexi AVC-R was a boost controlle. Booth can be replaced by a fully customized MegaSquirt unit. And, you can get a MegaSquirt from Reverent much cheaper than buying the two Apexi units.

this is definatly a concern and and the part the reason im thinking about puttin the apexi stuff back in , that and the fact that the sub harness for them still seems to be in tact.

From what I can now tell, the main issue now falls on the factory ECU. It the main cause, not the MAF like I thought or the classic BOG symptom bigx5murf is thinking. The factory ECU can't adjust outside the set parameters and it causing the idle to drop below and stall the motor out when slowing down. It can be cased by too big of fuel injectors and the ECU is dumping too much fuel,

it does sound like backfiring BUT from the engine bay not the exhaust. I WILL say from time to time i DO get a "POP" from the exhaust from time to time, just going through the gears, normal driving NOT getting into it. doesnt seem to be an issue however id like to know if im shooting a flame ( i cant tell from the drivers seat)

Again, I go back to what I said above. If your hearing a pop from the engine bay, you could have a intake backfire. I seen this happen a lot when around older generations of American muscle. This is caused by improper tuned ECU and timing is backward, meaning the factory ECU sucks. Period. As for another note, since your running a vent to atmosphere HKS SSQV, you can be dumping metered air and that can also upset the fuel air ratio. It not recommended running a VTA on a metered car unless the MAF is between the BOV and Throttle Body.

[bigx5murf]

For infamous bog check here.

http://www.mazda-speed.com/forum2/in...c,21621.0.html