rought noise during moderate acceleration
#1
rought noise during moderate acceleration
Hello I have a 2004 rx-8 with a 13b motor. Car has 55K miles but motor is only 18K on it. (hydo locked with a stupid cold air intake live and learn huh)
okay here is the situation, car starts rihgt up every time cold or hot. I always use 91 93 octain depends whats advailable. oil change regulary between 3-3.5K miles. the car sat when i was deployed for 15 months. when i got back i changed coil packs, plugs, plug wires, and did a oil change and fuel stabilizer in the 1/8 tank i left in it and topped with fresh gas. the car idles very smooth but when i go to drive it it makes a rumble noise and engine vibrates. i cleaned the MAF sensor and it picks RPM's up faster still rumble present. I sea foamed the motor still present. I pulled the plugs and put 2oz of MMO in each rotor houseing spun by hand with 17 mm socket, cranked to removes left over MMO with plugs removed, rumble still present. I did a compression test got FrontRoter trail plug 95 dry 115 with a bit of MMO same for the Front Rotor lead plug. and the rear rotor housing I got 112 dry and 115 wet. i removed the shreder valve and got 3 even pulses from each rotor housing all about 38 PSI. what could be causing the rumble. I have a missfire code but cleaned my rx8 eccentric shaft position sensor and drove it and only git a miss in high above 6.5k rpm any ideas? going to remove exhaust and check for restrictions today.
Also have a new air filter installed.
* when the car was in storage it was supposedly started and idles for 30 mins every 1st of the month i know that can fould plugs hence whil i replaced them.
any help will be greatly appriciated. I have a cobb tuner so I can look at PIDs but all seem normal. AVG 22 MPG curently driven 282 miles since i took it out of storage sorry for the long write up just wanted to give as much info as possible
Ryan
okay here is the situation, car starts rihgt up every time cold or hot. I always use 91 93 octain depends whats advailable. oil change regulary between 3-3.5K miles. the car sat when i was deployed for 15 months. when i got back i changed coil packs, plugs, plug wires, and did a oil change and fuel stabilizer in the 1/8 tank i left in it and topped with fresh gas. the car idles very smooth but when i go to drive it it makes a rumble noise and engine vibrates. i cleaned the MAF sensor and it picks RPM's up faster still rumble present. I sea foamed the motor still present. I pulled the plugs and put 2oz of MMO in each rotor houseing spun by hand with 17 mm socket, cranked to removes left over MMO with plugs removed, rumble still present. I did a compression test got FrontRoter trail plug 95 dry 115 with a bit of MMO same for the Front Rotor lead plug. and the rear rotor housing I got 112 dry and 115 wet. i removed the shreder valve and got 3 even pulses from each rotor housing all about 38 PSI. what could be causing the rumble. I have a missfire code but cleaned my rx8 eccentric shaft position sensor and drove it and only git a miss in high above 6.5k rpm any ideas? going to remove exhaust and check for restrictions today.
Also have a new air filter installed.
* when the car was in storage it was supposedly started and idles for 30 mins every 1st of the month i know that can fould plugs hence whil i replaced them.
any help will be greatly appriciated. I have a cobb tuner so I can look at PIDs but all seem normal. AVG 22 MPG curently driven 282 miles since i took it out of storage sorry for the long write up just wanted to give as much info as possible
Ryan
#3
Yes all lead and trail plug wires are seater properly. And lead and trail plugs are in the proper location just incase anyone suggest this.
update did not pull exhaust off some bolts are rusted and will need replace will drop it when i pick some new bolts up.
Any info on clogged cat causeing a rumble? is this rumble what pre ignition/detonation sounds like on a rotary?
only thing i can think of is a exhaust or base engine problem if anyone has any other ideas i will gladly try them out.
I am going to try a octain booster and run it again tonight.
I currently am back to the stock ecu tune and no change, any one use COBB tuning software what is the ign seperation at idle and 5-6k rpm's i would like to check with a known good motor.
thanks in advance
update did not pull exhaust off some bolts are rusted and will need replace will drop it when i pick some new bolts up.
Any info on clogged cat causeing a rumble? is this rumble what pre ignition/detonation sounds like on a rotary?
only thing i can think of is a exhaust or base engine problem if anyone has any other ideas i will gladly try them out.
I am going to try a octain booster and run it again tonight.
I currently am back to the stock ecu tune and no change, any one use COBB tuning software what is the ign seperation at idle and 5-6k rpm's i would like to check with a known good motor.
thanks in advance
#4
Separation at idle is -15, it will vary from 5 at low load to 15 at high load at 5-6k rpm.
Detonation sounds is metallic sounding, like pennies in a can at low rpm, or like someone crushing an aluminum can at high rpm (this is the bad kind.)
Detonation sounds is metallic sounding, like pennies in a can at low rpm, or like someone crushing an aluminum can at high rpm (this is the bad kind.)
#5
Could be a stuck SSV or APV? Normally SSV opens at 6250rpm.
APV is always open on stock tune, but probably won't cause problems until past 4500rpm if it is stuck closed. You can try manipulating them with a long screwdriver to see they move freely. Should throw a code, but maybe not right away.
APV is always open on stock tune, but probably won't cause problems until past 4500rpm if it is stuck closed. You can try manipulating them with a long screwdriver to see they move freely. Should throw a code, but maybe not right away.
#6
Alright what is the SSV and APV and where are they located and what is there intended purpose for operation. sorry not to familure with these parts. Im still learning. if you give me a fast overlook on how to test i sure i will figure it out.
#7
Grasshopper
iTrader: (1)
Though its easy to check for cracks.
Plus, when doing a compression test, you also need to account for the RPM and make sure the engine is warm
Normal compression is 120psi with a minimum of 98.6psi
Will it rumble if the vehicle is stationary and you rev the engine?
Might be easier if we could hear this rumble.
Possible to take a video of this?
Not a bad idea..
More like 3250rpm
Last edited by Jon316G; 07-02-2011 at 07:49 PM.
#8
I'm sure you can find detailed instructions with a search, but they are valves on the intake manifold that open at different times during operation to improve air flow. Sort of like piston engines have variable valve systems.
They are controlled by solenoids, which can fail, and oil blowby in the intake can also make them stick.
Look behind the alternator under the intake, they are yellowish plated steel. You can find a tab on them that the solenoid pushes on to open them, and they spring shut. Should move with little resistance.
They are controlled by solenoids, which can fail, and oil blowby in the intake can also make them stick.
Look behind the alternator under the intake, they are yellowish plated steel. You can find a tab on them that the solenoid pushes on to open them, and they spring shut. Should move with little resistance.
#13
Surf Hard, Drive Hard
Join Date: Feb 2007
Location: Indialantic, Florida
Posts: 7,840
Likes: 0
Received 12 Likes
on
9 Posts
Rumble.....not a chatter or clicking sound?
That's the first thing we need to know......if no video of sound.
I was thinking motor mounts too Jon, but not now.....just like you.
Guess we could ask if the idle is okay? Forget it, I see that it is.
Is the car shaky at idle? Forget it....I see it's not and it's okay at idle.
By the way, didn't I read you had a misfire or CEL? If so, get it read..............It's entirely possible that it's a bad coil....even thogh recently changed I suppose......right?
For the sake of argument, do you do the 20 brake stomp reset after any of this?
And for the love of God, please use the "Enter" key!
Oltmann, Jon316 is one of the most knowledgeable guys on here....especially when it comes to the SSV and APV. Don't get all torqued out cause he point out that you were wrong.
That's the first thing we need to know......if no video of sound.
I was thinking motor mounts too Jon, but not now.....just like you.
Guess we could ask if the idle is okay? Forget it, I see that it is.
Is the car shaky at idle? Forget it....I see it's not and it's okay at idle.
By the way, didn't I read you had a misfire or CEL? If so, get it read..............It's entirely possible that it's a bad coil....even thogh recently changed I suppose......right?
For the sake of argument, do you do the 20 brake stomp reset after any of this?
And for the love of God, please use the "Enter" key!
Oltmann, Jon316 is one of the most knowledgeable guys on here....especially when it comes to the SSV and APV. Don't get all torqued out cause he point out that you were wrong.
Last edited by Mazurfer; 07-02-2011 at 08:43 PM.
#16
Release the twins.
still amazed at the rx8 club ethics policy. otlmann, you could have look in Accesstuner Race for the numbers of when they open/close, and what not.
I really wish i would have taken my APV System apart... i now have a APV stuck open code... but then again, i bought the car blown, so i wouldn't have known about it, and the books says you gotta pull the motor to get to the APV... right.... the book also said pull the motor out the bottom..
EDIT: just saw your SSV VDI AVP VIdeo ...Jon316g... looks like i was right and getting to the avp is going to be easy. thanks.
+1 for sound clips.
and +1 for getting your misfire sorted, why chase one problem down and leave another? who knows they may be tied together after all.
Consider this. you can hold a hose to your ear and use it as a stethoscope. use for vacuum leaks and smalled rattles..
(like loose exhaust heat shielding)
I really wish i would have taken my APV System apart... i now have a APV stuck open code... but then again, i bought the car blown, so i wouldn't have known about it, and the books says you gotta pull the motor to get to the APV... right.... the book also said pull the motor out the bottom..
EDIT: just saw your SSV VDI AVP VIdeo ...Jon316g... looks like i was right and getting to the avp is going to be easy. thanks.
+1 for sound clips.
and +1 for getting your misfire sorted, why chase one problem down and leave another? who knows they may be tied together after all.
Consider this. you can hold a hose to your ear and use it as a stethoscope. use for vacuum leaks and smalled rattles..
(like loose exhaust heat shielding)
Last edited by lastphaseofthis; 07-02-2011 at 08:51 PM.
#17
Grasshopper
iTrader: (1)
Its fine to be confused... there is a lot to comprehend and even I still have much learning to do.
Best thing is to research (since much has been discussed) and ask questions.
Worst thing you can do is argue with those who are trying to teach you, even if you take it as a personal "shot" (which isn't always the case).
Admit you're wrong and people might actually give you some lessons, fight them and you'll be left confused...
Best thing is to research (since much has been discussed) and ask questions.
Worst thing you can do is argue with those who are trying to teach you, even if you take it as a personal "shot" (which isn't always the case).
Admit you're wrong and people might actually give you some lessons, fight them and you'll be left confused...
#18
Grasshopper
iTrader: (1)
I don't wish to thread jack or deviate too far from the OPs problem...
That code could be the a result of faulty wiring or connector to the APV motor (or its simply not plugged in).
I use a 12VDC supply and a DPDT switch to cycle the valves (as shown in my link above... post #7).
Here is what it looks like in the car:
You can actually hear the valves cycling and it'll give you an idea if the valves are truly stuck (and also check the wiring/connector too).
That code could be the a result of faulty wiring or connector to the APV motor (or its simply not plugged in).
I use a 12VDC supply and a DPDT switch to cycle the valves (as shown in my link above... post #7).
Here is what it looks like in the car:
You can actually hear the valves cycling and it'll give you an idea if the valves are truly stuck (and also check the wiring/connector too).
Last edited by Jon316G; 07-02-2011 at 08:50 PM.
#19
Jon, you're ridiculous. I asked about the ECU table, and I didn't get a response, you simply insulted me. What is that about? I'm a noob, but not noob enough to help? That makes you pretty useless to me.
lastphaseofthis, I have looked in AccessTuner, that is why I was (am) confused.
lastphaseofthis, I have looked in AccessTuner, that is why I was (am) confused.
#21
-okay checked motor mounts only found 2 one on each side near strut towers both are clean and show no cracks in the rubber.
-the engine was cold when i did compression test this might account for the lower numbers but they were not to low from what i have read here.
-yes it rumbles/chatters in neutral not engaging the transmition will try to make a vidieo of the sound tomorrow to clearify if its a rumble or chatter from a experienced ear. many thanks.
-yes all 4 coils i replaced and all wires are routed to the correct plug 99% sure.. second guesing now but it made same noise before i replaced coils.
-will read up how to check ssv and apv and get back to you with my findings.
***so i found a small vac line in rear of the throttle plate on upper intake manifold it has a one way check valve in it and its sucking in air like a vac leak, can not find its origional location maybe i knocked it off doing my coils and plugs any ideas i looked at a diagram https://www.rx8club.com/series-i-tech-garage-22/vacuum-hose-diagram-214910/ and i think its the one high lighted in green going to the VDI sol valve. once again not sure what VDI means but i know it needs to be connected will find its location in the day light tommorow.
For all the positive help thanks and no need to insult people here fellas we are all car enthusiast.
-the engine was cold when i did compression test this might account for the lower numbers but they were not to low from what i have read here.
-yes it rumbles/chatters in neutral not engaging the transmition will try to make a vidieo of the sound tomorrow to clearify if its a rumble or chatter from a experienced ear. many thanks.
-yes all 4 coils i replaced and all wires are routed to the correct plug 99% sure.. second guesing now but it made same noise before i replaced coils.
-will read up how to check ssv and apv and get back to you with my findings.
***so i found a small vac line in rear of the throttle plate on upper intake manifold it has a one way check valve in it and its sucking in air like a vac leak, can not find its origional location maybe i knocked it off doing my coils and plugs any ideas i looked at a diagram https://www.rx8club.com/series-i-tech-garage-22/vacuum-hose-diagram-214910/ and i think its the one high lighted in green going to the VDI sol valve. once again not sure what VDI means but i know it needs to be connected will find its location in the day light tommorow.
For all the positive help thanks and no need to insult people here fellas we are all car enthusiast.
#22
Grasshopper
iTrader: (1)
so i found a small vac line in rear of the throttle plate on upper intake manifold it has a one way check valve in it and its sucking in air like a vac leak, can not find its origional location maybe i knocked it off doing my coils and plugs any ideas i looked at a diagram https://www.rx8club.com/showthread.php?t=214910 and i think its the one high lighted in green going to the VDI sol valve. once again not sure what VDI means but i know it needs to be connected will find its location in the day light tommorow.
If so, that is the VFAD (orange highlight in your link).
Is the one-way valve between the throttle body and the air box?
#23
Surf Hard, Drive Hard
Join Date: Feb 2007
Location: Indialantic, Florida
Posts: 7,840
Likes: 0
Received 12 Likes
on
9 Posts
Well, it should either have a hose on it or be capped, let's put it that way.
Also, check all hose connections that lead to the accordion tube. Lots of times the plastic elbows right at the accordion get busted or cracked. that's not good either.
Last edited by Mazurfer; 07-03-2011 at 07:27 AM.
#24
the tube is capped now since i have a aem cold air intake i now recall during the install i just reversed the one way check valve because i never had a cap handy.
okay so went driving last night and figured out it seems to be trottle pos related. if i am doing 30mph at low rpm in 4th its making the noise but if i depress the throttle it instantly goes away well before my rpm's even pick up.
I hooked up my cobb tuner and took off intake piping and pressed my throttle. my throttle plate did not move at all till i was close to 70% pedal depressed, got the percent from my tuner going to make a vid and post right now. this way it will be more understood.
??i know the electronic throttle will throw codes but is it possible for the potentomiter to have dead spots in it where it wont read and move the throttle plate?
okay so went driving last night and figured out it seems to be trottle pos related. if i am doing 30mph at low rpm in 4th its making the noise but if i depress the throttle it instantly goes away well before my rpm's even pick up.
I hooked up my cobb tuner and took off intake piping and pressed my throttle. my throttle plate did not move at all till i was close to 70% pedal depressed, got the percent from my tuner going to make a vid and post right now. this way it will be more understood.
??i know the electronic throttle will throw codes but is it possible for the potentomiter to have dead spots in it where it wont read and move the throttle plate?
#25
Surf Hard, Drive Hard
Join Date: Feb 2007
Location: Indialantic, Florida
Posts: 7,840
Likes: 0
Received 12 Likes
on
9 Posts
the tube is capped now since i have a aem cold air intake i now recall during the install i just reversed the one way check valve because i never had a cap handy.
okay so went driving last night and figured out it seems to be trottle pos related. if i am doing 30mph at low rpm in 4th its making the noise but if i depress the throttle it instantly goes away well before my rpm's even pick up.
I hooked up my cobb tuner and took off intake piping and pressed my throttle. my throttle plate did not move at all till i was close to 70% pedal depressed, got the percent from my tuner going to make a vid and post right now. this way it will be more understood.
??i know the electronic throttle will throw codes but is it possible for the potentomiter to have dead spots in it where it wont read and move the throttle plate?
okay so went driving last night and figured out it seems to be trottle pos related. if i am doing 30mph at low rpm in 4th its making the noise but if i depress the throttle it instantly goes away well before my rpm's even pick up.
I hooked up my cobb tuner and took off intake piping and pressed my throttle. my throttle plate did not move at all till i was close to 70% pedal depressed, got the percent from my tuner going to make a vid and post right now. this way it will be more understood.
??i know the electronic throttle will throw codes but is it possible for the potentomiter to have dead spots in it where it wont read and move the throttle plate?
Quotes from Jon316G:
The positioning sensor for the throttle body is built into the assembly.
So if the sensor, motor, or valve components are bad, the whole thing needs to be replaced.
If you want to try a couple things I would first clean the throttle body.
Just use Carb Cleaner and a shop rag to wipe around the valve.
Open the valve with your finger and wipe around it.
I usually remove the four bolts holding the TB to the UIM to clean it better (no need to remove the two coolant lines).
Then you can visually watch the valve open and close to see if there are hesitation or "skips" while traveling.
The valve is controlled by a stepper motor, so simply have someone in the car, turn the key to 'ON' (no need to start it), and have them press and release the gas pedal.
Then watch the valve open and close.
End of quote!
Last edited by Mazurfer; 07-04-2011 at 08:00 AM.