Throttle Body Behavior
#1
Throttle Body Behavior
Howdy folks,
So need some assistance, working on an '04 with ~80k miles. Car was started twice today for some short moves now it won't start at all. Original thought was flooding. Waited a few hours tried to start it still no go. Pulled the plugs to find out they where completely shot, so we replaced them but the car still won't start.
In the process of doing all this we noticed a very high pitched squeal coming from the throttle body. Going though the trouble shooting guide in the FSM, the throttle body passes inspection, however I still question it.
What is the normal behavior of the throttle body under start up? When we put the key in the ignition the throttle plate doesn't move, when we turn the engine over the throttle plate still doesn't move. It would seem to me that the plate would need to open in order for the engine to take in air to start.
Anyone have any ideas or suggestions? James did I leave out anything?
So need some assistance, working on an '04 with ~80k miles. Car was started twice today for some short moves now it won't start at all. Original thought was flooding. Waited a few hours tried to start it still no go. Pulled the plugs to find out they where completely shot, so we replaced them but the car still won't start.
In the process of doing all this we noticed a very high pitched squeal coming from the throttle body. Going though the trouble shooting guide in the FSM, the throttle body passes inspection, however I still question it.
What is the normal behavior of the throttle body under start up? When we put the key in the ignition the throttle plate doesn't move, when we turn the engine over the throttle plate still doesn't move. It would seem to me that the plate would need to open in order for the engine to take in air to start.
Anyone have any ideas or suggestions? James did I leave out anything?
#3
charles,
the car is trying to turn over just not starting, its getting spark and you can feel the motor try to start. the battery is good and the started is good. is there anything else you guys would recommend testing and/or replacing.
thanks again everyone
the car is trying to turn over just not starting, its getting spark and you can feel the motor try to start. the battery is good and the started is good. is there anything else you guys would recommend testing and/or replacing.
thanks again everyone
#5
Charles you flatter me, I wish I had a shop, I'm just an avid rx7 owner trying to help out my rx8 brethren. I have quicky discovered that the 8 and 7 are quite different. I'll be heading over to James' house with my compression tester after work and I'll post the results. Thanks for all the help!
#7
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So when the solenoid is done the car wont start? Cuz im having a problem right now i have thread made on here my car didnt want to start but we and after a few hours it started but shaking severely i changed the spark plugs and then turned it back on and the shaking is still happening
#8
Metatron
iTrader: (1)
Sounds like it is/was flooded.
The shaking is probably one plug not firing, sounds like you need to get the engine hot and see if it behaves. See if the shaking stops after a good fast drive to clear things out.....
S
The shaking is probably one plug not firing, sounds like you need to get the engine hot and see if it behaves. See if the shaking stops after a good fast drive to clear things out.....
S
#9
rx8ohiotech
Join Date: Oct 2010
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the throttle body will make a bunch of noise sometimes even when the engine is not running. it will also stay partially open when engine and ignition is off. a buzzing or squealling is also normal. the pcm actuates it to either rezero the position sensors or a programmed opening to prohibit sticking.
#11
#12
Momentum Keeps Me Going
So when the solenoid is done the car wont start? Cuz im having a problem right now i have thread made on here my car didnt want to start but we and after a few hours it started but shaking severely i changed the spark plugs and then turned it back on and the shaking is still happening
#14
well, just finished the compression test, its 60 in the rear and 70 up front. looks like i'm going to need a rebuild. does anyone have any ideas where to get the best $$$ for a kit??? please let me know, and again thank you all for your advice!!!!
#15
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Please give us some more info... How many miles? What service and parts has the car had? M/T or A/T? Have you been having any other problems. What mods have you got? Where are you? Do you have a Rotary compression tester?
#17
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There are three sides to a rotor....traditional will give you the highest side of three sides. The engine warranty is 8year or 100K. Are you over that? With a speed of 205rpm it sounds like a old style starter 2004 or 2005 and a weak battery.
Last edited by Old Rotor; 10-06-2010 at 07:20 PM.
#18
going by the chart in the FSM at 200rpm the compression should be 102psi. James is going to jump it and see if the starter RPM increases to see if we can rule out weak battery
#20
the car has 82k on it. parts, i've replaced the battery about 5 months ago, replaced the starter yesterday. its a m/t i have never had any problems with the car until monday when it decided to die on me. as far as mods go, it has an aftermarket exhaust and intake, but all stock besides that. the car is in south carolina. rotary compression tester i do not have. we did a standard compression test and it was 60 in read 70 in the front.
#23
I had the same issue and ..
I would start with a compression/intake vacuum test as this particular car is of the troublesome 2004-2005 models that had shitty starters, weak batteries, and low OMP volumes from the factory. Mazda, in all their stupidity, performed a bunch of Band-Aid solutions to address the "hard/no start" issue and it was low compression all along from the OMP volumes (which I and Paul Yaw both wrote about 5 years ago). When the 2004-2005s get over 50K miles, they ALL need compression tests. Otherwise, you will be chasing your tails at Devil Motorsports. A compression test will also tell you the cranking speed of the engine and we can then determine if a new battery or starter is suggested.
Once you get the car running again, you may want to suggest your customer get a Cobb AccessPort and BHR Ignition System. Those are both definite "must haves" for the RX-8.
Once you get the car running again, you may want to suggest your customer get a Cobb AccessPort and BHR Ignition System. Those are both definite "must haves" for the RX-8.
#24
symptoms of bad throttle body
Howdy folks,
So need some assistance, working on an '04 with ~80k miles. Car was started twice today for some short moves now it won't start at all. Original thought was flooding. Waited a few hours tried to start it still no go. Pulled the plugs to find out they where completely shot, so we replaced them but the car still won't start.
In the process of doing all this we noticed a very high pitched squeal coming from the throttle body. Going though the trouble shooting guide in the FSM, the throttle body passes inspection, however I still question it.
What is the normal behavior of the throttle body under start up? When we put the key in the ignition the throttle plate doesn't move, when we turn the engine over the throttle plate still doesn't move. It would seem to me that the plate would need to open in order for the engine to take in air to start.
Anyone have any ideas or suggestions? James did I leave out anything?
So need some assistance, working on an '04 with ~80k miles. Car was started twice today for some short moves now it won't start at all. Original thought was flooding. Waited a few hours tried to start it still no go. Pulled the plugs to find out they where completely shot, so we replaced them but the car still won't start.
In the process of doing all this we noticed a very high pitched squeal coming from the throttle body. Going though the trouble shooting guide in the FSM, the throttle body passes inspection, however I still question it.
What is the normal behavior of the throttle body under start up? When we put the key in the ignition the throttle plate doesn't move, when we turn the engine over the throttle plate still doesn't move. It would seem to me that the plate would need to open in order for the engine to take in air to start.
Anyone have any ideas or suggestions? James did I leave out anything?