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help!! losing power backfiring and wont pass 2800 - 3000 rpm

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Old 02-08-12, 01:57 PM
  #26  
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Originally Posted by Law
Arthas,

Any updates? Is your car back to normal still? I am having the same issues you were. I haven't pulled any codes yet but it has been having the same hesitation/bogging/feeling of fuel cut past 3000rpm. I am going to check my y-pipe, crossover tube, and coupling/rubber joint as I know it's caked in oil. Then I'm going to reset the ECU as well. Hopefully this takes care of my issue, too.
Hi there, didn't check the code 6 yet... but, car is running perfectly... 0 issues... I'd say it was a problem between, grounds (the block ground was covered by oil...), fouled spark plugs, and maybe a small leak in the Y pipe...

+ I've replaced the fuel filter just to be in the safe side... and avoid any possible trouble in the future

Originally Posted by AzEKnightz
why not check ur codes before you reset your ecu and checking the rest of the list? Start with the basic, you dont wanna reset the ecu and "hope" for the car to cure itself.

-AzEKnightz
Ya, i agree... better check codes first, and inspect the fender splash guard to see if the wheel is rubbing through into the harness... as karack advised before...
Old 02-09-12, 08:39 AM
  #27  
Law
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Originally Posted by AzEKnightz
why not check ur codes before you reset your ecu and checking the rest of the list? Start with the basic, you dont wanna reset the ecu and "hope" for the car to cure itself.

-AzEKnightz
I thought that the car had to be throwing a check engine light for you to effectively pull codes. I will check the wiring behind the fender lining and trace the wires from the MAP sensor this weekend. But will I still pull error codes from the ECU if the car's check engine light hasn't popped up? (I know for a fact the check engine light indeed does work because it lit up when I replaced my vacuum lines and forgot to plug the TPS sensor back in)
Old 02-09-12, 10:04 AM
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Originally Posted by Law
I thought that the car had to be throwing a check engine light for you to effectively pull codes. I will check the wiring behind the fender lining and trace the wires from the MAP sensor this weekend. But will I still pull error codes from the ECU if the car's check engine light hasn't popped up? (I know for a fact the check engine light indeed does work because it lit up when I replaced my vacuum lines and forgot to plug the TPS sensor back in)
FDs in the state are pre-OBD2. That means it might not show you a check engine light but there's a possibility that a code(s) might be stored in the memory.

-AzEKnightz
Old 02-09-12, 10:27 AM
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Originally Posted by AzEKnightz
FDs in the state are pre-OBD2. That means it might not show you a check engine light but there's a possibility that a code(s) might be stored in the memory.

-AzEKnightz
Thanks a bunch for the help I'll update with my findings.
Old 02-09-12, 01:18 PM
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But will I still pull error codes from the ECU if the car's check engine light hasn't popped up?
If they are there, you will be able to read them. Not all fault codes light the CEL (for some reason).
Old 02-11-12, 11:59 AM
  #31  
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Originally Posted by wstrohm
If they are there, you will be able to read them. Not all fault codes light the CEL (for some reason).
Originally Posted by AzEKnightz
FDs in the state are pre-OBD2. That means it might not show you a check engine light but there's a possibility that a code(s) might be stored in the memory.

-AzEKnightz
I pulled the code and got 45 (Solenoid valve - charge control). This was the only code I got. From what I can understand, the solenoids and majority of the vacuum lines primarily function the sequential twins, correct? So if there is an issue with the charge control solenoid valve or the vacuum lines, wouldn't it mainly just cause the car to not boost or at the most feel restricted?... my car feels like it's completely cutting out past 3k as if it's in limp mode.

After this I poked around the engine bay a bit, replaced a kinked hose, checked for anything disconnected, looked over the MAP sensor, and reset the ECU. Took the car for a test drive and it still was acting up past 3k. I pulled a diagnostic code again and got the number 45 yet again.

In reference to the MAP sensor being a possible culprit, I checked my fender liner and there are no points of exposure from any kind of damage. My car is stock height.

Here's a little more history/info:

My car is a '95 PEP model. All stock. Suspension, engine and exterior wise. All stock. It was running fine. About 4 weeks ago it began to have problems with a fluctuating idle and very high rpm under electrical load. I then did a vacuum job replacing all the old lines with silicone Hose Technique hoses. It ran awesome after that for about a week.

And then one day during lunch, I go to the gas station to pump gas. As soon as I leave the gas station the car begins to have these issues where it feels like it's in limp mode (tainted gas from the gas station maybe?). After this, I went ahead and changed the O2 sensor thinking that this could also have been a cause for the fluctuating idle. O2 sensor didn't help.

I've been reading up on the OMP causing a car to go into limp mode.

Any thoughts on the culprit?

Thanks again!
Old 02-11-12, 12:53 PM
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Regarding Code #45, a fault of the Charge Control solenoid, per page F-162 of the 1994 RX-7 FWM, terminal 4T of the PCME should remain at below 1.0 volts for engine speeds up to 5500 rpm (manual transmission) or 5250 rpm (auto). Above that rpm, the voltage should jump to B+.

(Just FYI.)
Old 02-11-12, 01:38 PM
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Originally Posted by Law
I pulled the code and got 45 (Solenoid valve - charge control). This was the only code I got. From what I can understand, the solenoids and majority of the vacuum lines primarily function the sequential twins, correct? So if there is an issue with the charge control solenoid valve or the vacuum lines, wouldn't it mainly just cause the car to not boost or at the most feel restricted?... my car feels like it's completely cutting out past 3k as if it's in limp mode.

After this I poked around the engine bay a bit, replaced a kinked hose, checked for anything disconnected, looked over the MAP sensor, and reset the ECU. Took the car for a test drive and it still was acting up past 3k. I pulled a diagnostic code again and got the number 45 yet again.

In reference to the MAP sensor being a possible culprit, I checked my fender liner and there are no points of exposure from any kind of damage. My car is stock height.

Here's a little more history/info:

My car is a '95 PEP model. All stock. Suspension, engine and exterior wise. All stock. It was running fine. About 4 weeks ago it began to have problems with a fluctuating idle and very high rpm under electrical load. I then did a vacuum job replacing all the old lines with silicone Hose Technique hoses. It ran awesome after that for about a week.

And then one day during lunch, I go to the gas station to pump gas. As soon as I leave the gas station the car begins to have these issues where it feels like it's in limp mode (tainted gas from the gas station maybe?). After this, I went ahead and changed the O2 sensor thinking that this could also have been a cause for the fluctuating idle. O2 sensor didn't help.

I've been reading up on the OMP causing a car to go into limp mode.

Any thoughts on the culprit?

Thanks again!
Want to bet on the CCV solenoid? =)

If you "fixed" the kinked hose, and reset the ECU and STILL get the same thing. The computer will automatically put your car back into limp mode, and in-term you will get your fuel cut/hesitation/bogging down at 3k rpm.

Replace that CCV solenoid OR simply upgrade to my custom solenoid kit here, which will FIX all your solenoid problem + a much better reliability system that boost properly and you'll be glad you did.

Check out my signature on the bottom of my post here.

or simply go HERE

-AzEKnightz
Old 02-12-12, 11:07 AM
  #34  
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Hi, I was getting too the code 45 + 13... and karack told me the following

Originally Posted by Karack
if you're getting a map sensor code do the check of the left front harness i described earlier, that is usually the cause for that code.


usually your issue is attributed to the Y pipe rubber coupler cracking and/or blowing out, losing boost. or the wiring under the left front fender getting munched from wider wheels on lowered suspension, turn the wheel and inspect the fender splash guard to see if the wheel is rubbing through into the harness.
honesty before replacing something... i would check this first... or do the same thing as me inspect the Y- pipe... it has sense.. due to if there is a small leak... sensors/solenoids will not operate properly...
Old 02-13-12, 12:53 PM
  #35  
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Originally Posted by AzEKnightz
Want to bet on the CCV solenoid? =)

If you "fixed" the kinked hose, and reset the ECU and STILL get the same thing. The computer will automatically put your car back into limp mode, and in-term you will get your fuel cut/hesitation/bogging down at 3k rpm.

Replace that CCV solenoid OR simply upgrade to my custom solenoid kit here, which will FIX all your solenoid problem + a much better reliability system that boost properly and you'll be glad you did.

Check out my signature on the bottom of my post here.

or simply go HERE

-AzEKnightz
I am reading into this set up right here. Quite nice. I'm currently getting to pulling out the Charge control solenoid valve to test it out. If it's bad, I may wait a paycheck or two and buy the set up to replace everything. I'll update as soon as I have time to work on the car again. Thanks for the info guys. This site is great!
Old 04-26-13, 06:41 PM
  #36  
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yes, I make it a habit to reset ECU after I do any mods/maintenance.
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