HELP: Missing power under 5k rpm!?!?!?
07-03-2008, 08:41 PM
#1
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HELP: Missing power under 5k rpm!?!?!?
I've had this problem for about three weeks now. Under 5k rpm my car is lacking about half its normal power. After 5k rpm it still feels strong. When taking off from a stop, or accelerating under 5k, the engine sounds like it's being flooded; however, it starts and idles perfectly fine.
Here is the interesting part: when the car is cold. It feels very strong from idle all the way to redline. After the car warms up I loose most of my down low power.
The only engine mods I have are RB intake+duct and RB exhaust. Both mods have been installed for over 2 years without any issues. The car has 57k miles on it.
I tried the normal fixes. I installed new plugs. Checked all the fluids. Cleaned the air filter. I even completely reset the computer.
Help?
Here is the interesting part: when the car is cold. It feels very strong from idle all the way to redline. After the car warms up I loose most of my down low power.
The only engine mods I have are RB intake+duct and RB exhaust. Both mods have been installed for over 2 years without any issues. The car has 57k miles on it.
I tried the normal fixes. I installed new plugs. Checked all the fluids. Cleaned the air filter. I even completely reset the computer.
Help?
07-03-2008, 08:54 PM
#3
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My first guess was the coils as well. I looked at the bottom of them about a year ago and they didn't look that bad. Only a little white. I took it to the dealer the next day and they said it wasn't enough to warrant a replacement.
If it was the cat, shouldn't I have power down low and none at the top?
07-03-2008, 09:16 PM
#4
you can't tell if the coils are good by looking on the bottom. Replace the coils as your first step. They tend to last 12-40k miles usually, so you're overdue IMO. I usually change them once a year just to avoid having issues.
When the BHR coils come out, I can stop that cycle.
When the BHR coils come out, I can stop that cycle.
07-03-2008, 09:46 PM
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When I cleaned the air filter I noticed that my intake screen was badly ripped. After replacing it with a new one, the car did seem to run a little better. It could have just been my imagination though.
07-03-2008, 10:01 PM
#10
Some people like to use MAF cleaner from a spray can. I just use a little rubbing alcohol on a Q-Tip. Try checking each individual wire as it runs into the connector and take a look at the connector interface on the sensor, too.
07-03-2008, 10:54 PM
#14
wait wait wait. What !
STOP. Dont FREAKING touch anything on the MAF !
Go buy a can of MAF cleaner, its in a spray can and it cost like 4 bucks, spray clean it, dont touch anything on it. remember to clean the inside too. Search for DIY
dont cry if u mess it up by touching them, that thing is like a 100 something bux item.
STOP. Dont FREAKING touch anything on the MAF !
Go buy a can of MAF cleaner, its in a spray can and it cost like 4 bucks, spray clean it, dont touch anything on it. remember to clean the inside too. Search for DIY
dont cry if u mess it up by touching them, that thing is like a 100 something bux item.
07-03-2008, 10:55 PM
#15
07-03-2008, 11:54 PM
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Well, I took it out and cleaned it with rubbing alcohol and they blew it with the air compressor. After reinstalling it the car idled rough for about 30 seconds and them evened out. It now runs like before.
The problem still exist.
The problem still exist.
07-04-2008, 09:37 AM
#17
wait wait wait. What !
STOP. Dont FREAKING touch anything on the MAF !
Go buy a can of MAF cleaner, its in a spray can and it cost like 4 bucks, spray clean it, dont touch anything on it. remember to clean the inside too. Search for DIY
dont cry if u mess it up by touching them, that thing is like a 100 something bux item.
STOP. Dont FREAKING touch anything on the MAF !
Go buy a can of MAF cleaner, its in a spray can and it cost like 4 bucks, spray clean it, dont touch anything on it. remember to clean the inside too. Search for DIY
dont cry if u mess it up by touching them, that thing is like a 100 something bux item.
Jackson, relax. I have cleaned my MAF sensor countless times and it works fine. The part that shouldn't be "touched" is shrouded. If one doesn't handle the sensor like a gorilla it'll be fine. Blowing air on it, however, probably isn't good. Then again, he didn't touch it did he?
07-04-2008, 09:08 PM
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In my first 8 when this type thing happened to me, when I stopped and shut off the car it sound like a small pump was running, and ended up I had the compression loss issue, and that car had 17K on it, but I hope that this isn't the case for you. Have you tried what Razz1 suggested?
07-04-2008, 10:25 PM
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In my first 8 when this type thing happened to me, when I stopped and shut off the car it sound like a small pump was running, and ended up I had the compression loss issue, and that car had 17K on it, but I hope that this isn't the case for you. Have you tried what Razz1 suggested?
I'm working on attaining a compression tester from a friend. I need to do some searching to see what the compression should be and how to test it. That is unless anyone knows off hand.
07-04-2008, 10:46 PM
#22
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I did try it. It didn't stall; however, variables such as speed, incline, and gear all affect it. So his method, while a good preliminary test, doesn't definitively tell me anything.
I'm working on attaining a compression tester from a friend. I need to do some searching to see what the compression should be and how to test it. That is unless anyone knows off hand.
I'm working on attaining a compression tester from a friend. I need to do some searching to see what the compression should be and how to test it. That is unless anyone knows off hand.
You need a compression gauge without a "stop" so the needle can move back down after the compression stroke, watch and compare the high points on each rotor as the engine is turned over.
You may want to get a Mazda dealer to test the compression, but that is like pulling teeth, they don't want you to possibly prove you need a motor.
07-04-2008, 11:17 PM
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A normal compression gauge will not work; there are three areas for compression on each rotor...
You need a compression gauge without a "stop" so the needle can move back down after the compression stroke, watch and compare the high points on each rotor as the engine is turned over.
You may want to get a Mazda dealer to test the compression, but that is like pulling teeth, they don't want you to possibly prove you need a motor.
You need a compression gauge without a "stop" so the needle can move back down after the compression stroke, watch and compare the high points on each rotor as the engine is turned over.
You may want to get a Mazda dealer to test the compression, but that is like pulling teeth, they don't want you to possibly prove you need a motor.
I wonder if I can rent one.
07-05-2008, 12:13 AM
#24
I've seen a few people on these forums talk about running perfect when the engine is cold but lack of power due to bad compression when warm - that was how it was diagnosed by the dealer multiple times.
Happens because when the engine is cold you have a good seal, but when it gets warm the metals expand (like any engine) but a failing seal will not adjust to the expansion to create a good seal.. leading to this.
Happens because when the engine is cold you have a good seal, but when it gets warm the metals expand (like any engine) but a failing seal will not adjust to the expansion to create a good seal.. leading to this.
07-05-2008, 12:59 AM
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I did try it. It didn't stall; however, variables such as speed, incline, and gear all affect it. So his method, while a good preliminary test, doesn't definitively tell me anything.
I'm working on attaining a compression tester from a friend. I need to do some searching to see what the compression should be and how to test it. That is unless anyone knows off hand.
I'm working on attaining a compression tester from a friend. I need to do some searching to see what the compression should be and how to test it. That is unless anyone knows off hand.
I've seen a few people on these forums talk about running perfect when the engine is cold but lack of power due to bad compression when warm - that was how it was diagnosed by the dealer multiple times.
Happens because when the engine is cold you have a good seal, but when it gets warm the metals expand (like any engine) but a failing seal will not adjust to the expansion to create a good seal.. leading to this.
Happens because when the engine is cold you have a good seal, but when it gets warm the metals expand (like any engine) but a failing seal will not adjust to the expansion to create a good seal.. leading to this.