bad battery vs. bad alternator vs. bad compression
#1
learning
Thread Starter
Join Date: Apr 2007
Location: Jacksonville, FL
Posts: 56
Likes: 0
Received 0 Likes
on
0 Posts
bad battery vs. bad alternator vs. bad compression
Basically trying to figure out what I have here. I'm guessing both the first and last one but want to see what rx8club has to say. I just changed out the battery and spark plugs last June, and all the ignition coils and a newer catalytic converter this January. I just ordered a new set of spark plugs and wires because a water jet from an automatic car wash no **** disconnected one of my spark plugs, and I'm amazed to see that I didn't notice it until a couple days later when I noticed the car was acting funny. So I have a new set coming in because I'm worried I may have fouled/overworked the other three.
Anyway, nothing is more annoying and embarrassing now than having to fill up at the gas station. I shut down the car warm and rev it as always, but I still run into long and repeated starts. I checked the battery voltage and it reads 12.5 on a voltmeter, and when the car is running, it's at about 14 or so if I remember correctly. My car is fine once I get it running, so I assume that means the alternator is okay?
If the battery reads 12.5v, could it still be bad I guess because maybe it's not putting out the required cranking amps? How do you check that? I used my voltmeter and switched it to amps and am getting a reading of like 0.11 mA. That doesn't make sense, or the voltmeter I bought from Wal-Mart is screwed up or I'm doing something wrong. Just right now I got back from the gas station and spent over 2-3 minutes of cranking time before I finally got it started up, and only because I used one of those portable engine starters that puts out like 1200 cranking amps that I keep in my trunk on my last attempt.
So in my judgment, I think my battery is bad, but the one thing that confuses me is if I were to wait like 30 minutes to an hour, the car will start up fine. So in that case, how is it the battery? I checked the trunk light because I heard of that being a possible drain and it's not being left on. I have 92,000 miles on my car and plan on taking it in for a compression check soon, but until then, do I just have a bad battery, bad alternator, or bad compression? It doesn't make sense to me that a battery I bought in June would die so quickly.
Oh yeah, I have the new starter, too.
**P.S., what's a good starter cycle to use to make sure I don't burn out the starter? I typically crank for only ten seconds at a time.
Anyway, nothing is more annoying and embarrassing now than having to fill up at the gas station. I shut down the car warm and rev it as always, but I still run into long and repeated starts. I checked the battery voltage and it reads 12.5 on a voltmeter, and when the car is running, it's at about 14 or so if I remember correctly. My car is fine once I get it running, so I assume that means the alternator is okay?
If the battery reads 12.5v, could it still be bad I guess because maybe it's not putting out the required cranking amps? How do you check that? I used my voltmeter and switched it to amps and am getting a reading of like 0.11 mA. That doesn't make sense, or the voltmeter I bought from Wal-Mart is screwed up or I'm doing something wrong. Just right now I got back from the gas station and spent over 2-3 minutes of cranking time before I finally got it started up, and only because I used one of those portable engine starters that puts out like 1200 cranking amps that I keep in my trunk on my last attempt.
So in my judgment, I think my battery is bad, but the one thing that confuses me is if I were to wait like 30 minutes to an hour, the car will start up fine. So in that case, how is it the battery? I checked the trunk light because I heard of that being a possible drain and it's not being left on. I have 92,000 miles on my car and plan on taking it in for a compression check soon, but until then, do I just have a bad battery, bad alternator, or bad compression? It doesn't make sense to me that a battery I bought in June would die so quickly.
Oh yeah, I have the new starter, too.
**P.S., what's a good starter cycle to use to make sure I don't burn out the starter? I typically crank for only ten seconds at a time.
#2
Surf Hard, Drive Hard
Join Date: Feb 2007
Location: Indialantic, Florida
Posts: 7,840
Likes: 0
Received 11 Likes
on
9 Posts
Best way is go get the battery tested somewhere.
Is it the original?
Voltage readings are okay....not steller but okay at 12.5v with car off and 14.2v while running. It could still be bad.
You can't test the cranking amps the way you are tring to, so head to Autozone where they will check the battery and the alternator for free, but to be honest, it sounds like niether, or something is killing that battery quickly. Eliminate that and the alternator by having them tested.
Oh.............how do you know you have the new starter? Did you check it by the part number?
More after I re-read all you wrote.
Starter burst............I would say about 7-10 seconds followed by at least a good 15 second wait inbetween. I personally wouldn't go as long as 10 seconds, but that's just me.
so once running................no loss of power at all?
Is it the original?
Voltage readings are okay....not steller but okay at 12.5v with car off and 14.2v while running. It could still be bad.
You can't test the cranking amps the way you are tring to, so head to Autozone where they will check the battery and the alternator for free, but to be honest, it sounds like niether, or something is killing that battery quickly. Eliminate that and the alternator by having them tested.
Oh.............how do you know you have the new starter? Did you check it by the part number?
More after I re-read all you wrote.
Starter burst............I would say about 7-10 seconds followed by at least a good 15 second wait inbetween. I personally wouldn't go as long as 10 seconds, but that's just me.
so once running................no loss of power at all?
Last edited by Mazurfer; 02-04-2011 at 10:01 PM.
#3
learning
Thread Starter
Join Date: Apr 2007
Location: Jacksonville, FL
Posts: 56
Likes: 0
Received 0 Likes
on
0 Posts
Best way is go get the battery tested somewhere.
Is it the original?
Voltage readings are okay....not steller but okay at 12.5v with car off and 14.2v while running.
You can't test the cranking amps the way you are tring to, so head to Autozone where they will check the battery and the alternator for free, but to be honest, it sounds like niether, or something is killing that battery quickly.
Oh.............how do you know you have the new starter? Did you check it by the part number?
More after I re-read all you wrote.
Starter burst............I would say about 7-10 seconds followed by at least a good 15 second wait inbetween. I personally wouldn't go as long as 10 seconds, but that's just me.
so once running................no loss of power at all?
Is it the original?
Voltage readings are okay....not steller but okay at 12.5v with car off and 14.2v while running.
You can't test the cranking amps the way you are tring to, so head to Autozone where they will check the battery and the alternator for free, but to be honest, it sounds like niether, or something is killing that battery quickly.
Oh.............how do you know you have the new starter? Did you check it by the part number?
More after I re-read all you wrote.
Starter burst............I would say about 7-10 seconds followed by at least a good 15 second wait inbetween. I personally wouldn't go as long as 10 seconds, but that's just me.
so once running................no loss of power at all?
What numbers should I be looking for when it's off and on? You said 12.5 and 14 is not stellar, so what would be ideal?
#6
Registered User
Join Date: Dec 2009
Location: Paducah, Ky
Posts: 28
Likes: 0
Received 0 Likes
on
0 Posts
I'm having a similar situation. Car has been cranking slower than normal but i thought it was due to the weather. It has been in the 20's the last few days. Today my 8 would crank but not start. On the second try all the lights dimmed and it started clicking. If I wait a few minutes it will crank again but not start, then clicking. I had the battery tested and all they told me was that it was in the 12v range and was still good.
So I'm gonna get a jump tomorrow and see if it will start that way.
So I'm gonna get a jump tomorrow and see if it will start that way.
#7
Registered
I'm having a similar situation. Car has been cranking slower than normal but i thought it was due to the weather. It has been in the 20's the last few days. Today my 8 would crank but not start. On the second try all the lights dimmed and it started clicking. If I wait a few minutes it will crank again but not start, then clicking. I had the battery tested and all they told me was that it was in the 12v range and was still good.
So I'm gonna get a jump tomorrow and see if it will start that way.
So I'm gonna get a jump tomorrow and see if it will start that way.
#8
Registered
Cranking slower than usual, then degenerating into clicks rather than cranking, is a really good sign of a run-down or failing battery. If the charging system is OK (correct voltage when running) and the connections are good, then the battery's four years are up.
Ken
#10
Registered User
Join Date: Dec 2009
Location: Paducah, Ky
Posts: 28
Likes: 0
Received 0 Likes
on
0 Posts
Thanks for the input. I tried getting a jump. It didn't work. So I went to a different parts store and they said it was bad. I got a duralast with an 8 year warranty for 100.00
800 cranking amp and 650 cold cranking amp.
800 cranking amp and 650 cold cranking amp.
#11
I just had a similar frustrating situation. If I were to let my car sit for a couple of days the battery would be dead. The last time was a couple of days ago. I had just put in a brand new battery, went on a trip for a week, and when I tried to start it up...dead. Took it to the dealer and after a week they said it was my viper alarm. It was draining the battery when not being driven. I had also experienced some difficult starts, as witnessed by a few of my fellow 8 brother's here in San Antonio. I wouldn't have thought an alarm would draw that much power, but after the dealer took it out and let it sit, it was fine.
#13
Surf Hard, Drive Hard
Join Date: Feb 2007
Location: Indialantic, Florida
Posts: 7,840
Likes: 0
Received 11 Likes
on
9 Posts
4theride1..................just the trunk not being closed can drain the battery in as little as an evening or two. Seriously................hasn't happened to me, but one of the first thing we ask people to do is to look through the passthrough to insure the trunk light is out! Even without that issue, if you leave the car sit for longer periods of time, better get a battery tender!
As for the OP...................yeah, it could be compression, but.........(@Easy and @Jason).........I wanted him merely to go get the battery and alternator tested for free first! That's all. Notice that I did also ask about any loss of power...............no need to go into the particulars until the battery/alternator were eliminated.
As for the OP...................yeah, it could be compression, but.........(@Easy and @Jason).........I wanted him merely to go get the battery and alternator tested for free first! That's all. Notice that I did also ask about any loss of power...............no need to go into the particulars until the battery/alternator were eliminated.
Last edited by Mazurfer; 02-07-2011 at 03:29 PM.
#15
learning
Thread Starter
Join Date: Apr 2007
Location: Jacksonville, FL
Posts: 56
Likes: 0
Received 0 Likes
on
0 Posts
Okay just got a CEL today to my delight (sarcasm). Took it to AutoZone to get it read.
P0300 - cylinder misfire detection...whatever, I have new plugs and wires coming this week, and just installed new coils...hopefully that does the trick
and something completey new to me and am currently researching...
P2070 - intake manifold tuning valve stuck open
Dude at AutoZone had no idea what that meant. I've about had it with this car. Time to search I suppose.
P0300 - cylinder misfire detection...whatever, I have new plugs and wires coming this week, and just installed new coils...hopefully that does the trick
and something completey new to me and am currently researching...
P2070 - intake manifold tuning valve stuck open
Dude at AutoZone had no idea what that meant. I've about had it with this car. Time to search I suppose.
#16
Out of NYC
iTrader: (1)
Okay just got a CEL today to my delight (sarcasm). Took it to AutoZone to get it read.
P0300 - cylinder misfire detection...whatever, I have new plugs and wires coming this week, and just installed new coils...hopefully that does the trick
and something completey new to me and am currently researching...
P0300 - cylinder misfire detection...whatever, I have new plugs and wires coming this week, and just installed new coils...hopefully that does the trick
and something completey new to me and am currently researching...
if not, u need to check for clogged cat and/or compression test ur engine.
P2070 - intake manifold tuning valve stuck open
Dude at AutoZone had no idea what that meant. I've about had it with this car. Time to search I suppose.
Dude at AutoZone had no idea what that meant. I've about had it with this car. Time to search I suppose.
That means "SSV Stuck OPEN", its usually cause by people "babying" their car too much.
http://www.finishlineperformance.com...9-08-1929a.pdf
see the file. if you have the tools and right parts, it takes about 2-3 hours.
Many many times, you can get the valve "unstuck" by beat the **** out of your car, and or after your car has warm up (or after you beat the **** out of it) use a small screw driver keep tapping the LIM where the SSV is. or use a rubber hammer to lightly tap it. Sometimes it will unstuck the valve.
I am thinking of "replacing" my SSV bolt as well, but I will wait until I feel good one day to take my UIM apart and stuff.
Last edited by nycgps; 02-07-2011 at 09:28 PM.
#17
learning
Thread Starter
Join Date: Apr 2007
Location: Jacksonville, FL
Posts: 56
Likes: 0
Received 0 Likes
on
0 Posts
Change the plugs and wires see if it helps.
if not, u need to check for clogged cat and/or compression test ur engine.
of course the dude @ Autozone had no idea what that meant.
That means "SSV Stuck OPEN", its usually cause by people "babying" their car too much.
http://www.finishlineperformance.com...9-08-1929a.pdf
see the file. if you have the tools and right parts, it takes about 2-3 hours.
Many many times, you can get the valve "unstuck" by beat the **** out of your car, and or after your car has warm up (or after you beat the **** out of it) use a small screw driver keep tapping the LIM where the SSV is. or use a rubber hammer to lightly tap it. Sometimes it will unstuck the valve.
I am thinking of "replacing" my SSV bolt as well, but I will wait until I feel good one day to take my UIM apart and stuff.
if not, u need to check for clogged cat and/or compression test ur engine.
of course the dude @ Autozone had no idea what that meant.
That means "SSV Stuck OPEN", its usually cause by people "babying" their car too much.
http://www.finishlineperformance.com...9-08-1929a.pdf
see the file. if you have the tools and right parts, it takes about 2-3 hours.
Many many times, you can get the valve "unstuck" by beat the **** out of your car, and or after your car has warm up (or after you beat the **** out of it) use a small screw driver keep tapping the LIM where the SSV is. or use a rubber hammer to lightly tap it. Sometimes it will unstuck the valve.
I am thinking of "replacing" my SSV bolt as well, but I will wait until I feel good one day to take my UIM apart and stuff.
#18
learning
Thread Starter
Join Date: Apr 2007
Location: Jacksonville, FL
Posts: 56
Likes: 0
Received 0 Likes
on
0 Posts
found this video
http://www.vimeo.com/7093611
thanks to Jon316G
testing valves
http://www.vimeo.com/5353829
diy:
https://www.rx8club.com/series-i-do-yourself-forum-73/diy-remove-ssv-beta-teaser-video-184663/
http://www.vimeo.com/7093611
thanks to Jon316G
testing valves
http://www.vimeo.com/5353829
diy:
https://www.rx8club.com/series-i-do-yourself-forum-73/diy-remove-ssv-beta-teaser-video-184663/
Last edited by kcott; 02-07-2011 at 10:30 PM.
#19
Out of NYC
iTrader: (1)
^^ For parts you need, you can read that PDF, it tells u at the end.
for tools, hmm, if you have to ask and you plan on doing this yourself, you might want to get 10mm to 19mm socket and ratchet. from 1/4" to 1/2". you don't need all the sockets to do this job, but once u can complete this task, you will want to work on your car for the rest of its life. get good brand name tools with lifetime warranty if this is the path you're going.
for how to do it, yea follow Jon's video/pics/diy. and read the service manual 100 times.
if you will not do it yourself, hmm, doing it at dealership will cost you at least 600 bux.
for tools, hmm, if you have to ask and you plan on doing this yourself, you might want to get 10mm to 19mm socket and ratchet. from 1/4" to 1/2". you don't need all the sockets to do this job, but once u can complete this task, you will want to work on your car for the rest of its life. get good brand name tools with lifetime warranty if this is the path you're going.
for how to do it, yea follow Jon's video/pics/diy. and read the service manual 100 times.
if you will not do it yourself, hmm, doing it at dealership will cost you at least 600 bux.
Thread
Thread Starter
Forum
Replies
Last Post