# Surging RPMs? Any insight please.
**URL:** https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546
**Category:** NYSpeed Automotive
**Created:** [February 16, 2008, 9:44am UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546 "2008-02-16T09:44:42Z")
**Posts on this page:** 20
**Page:** 1
### Author:  [@Clean\_Baldy](https://forums.speedlife.net/u/Clean_Baldy)
#### Post date: [February 16, 2008, 9:44am UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/1 "2008-02-16T09:44:42Z")
I get in my mazdaspeed 6 to drive somewhere today, and right away i notice at idle, about every second, the RPMs were dipping down.
While driving, same thing. Every second, no power/dipping RPMs.
I popped the hood and it sounds like something in the fuel delivery system is hesitating. The engine sounds completely fine.
It was driving fine yesterday as well. I drove from Rochester to Buffalo, and then later went to dinner. Absolutely no issues when I went to bed.
Any ideas on what I can check/do myself?
I pulled the battery to reset the ECU, and that didn’t do anything.
I checked the air filter and it is nice and clean.
No leaks under the car.
???
---
### Author:  [@newman](https://forums.speedlife.net/u/newman)
#### Post date: [February 16, 2008, 9:45am UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/2 "2008-02-16T09:45:48Z")
how could you hear hesitation in the fuel delivery system?
---
### Author:  [@VANDIT](https://forums.speedlife.net/u/VANDIT)
#### Post date: [February 16, 2008, 9:51am UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/3 "2008-02-16T09:51:52Z")
> [@Clean Baldy"](#):
>
> I get in my mazdaspeed 6 to drive somewhere today, and right away i notice at idle, about every second, the RPMs were dipping down.
>
> While driving, same thing. Every second, no power/dipping RPMs.
>
> I popped the hood and it sounds like something in the fuel delivery system is hesitating. The engine sounds completely fine.
>
> It was driving fine yesterday as well. I drove from Rochester to Buffalo, and then later went to dinner. Absolutely no issues when I went to bed.
>
> Any ideas on what I can check/do myself?
>
> I pulled the battery to reset the ECU, and that didn’t do anything.
> I checked the air filter and it is nice and clean.
> No leaks under the car.
>
> ???
1. im with newman on the fuel
2. Pulling the battery WILL NOT RESET THE ECU were not in 1995 anymore
3. Unless you have 80,000 miles on your stock air filter, it will not cause this problem.
4. Is the CEL on?
No offence, but in your case bring it into a dealership…
Good luck
---
### Author:  [@nitroinsane](https://forums.speedlife.net/u/nitroinsane)
#### Post date: [February 16, 2008, 9:52am UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/4 "2008-02-16T09:52:26Z")
how many miles are on it? probably time for a tune up
---
### Author:  [@Clean\_Baldy](https://forums.speedlife.net/u/Clean_Baldy)
#### Post date: [February 16, 2008, 10:19am UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/5 "2008-02-16T10:19:32Z")
K. I was reading that a fuel pump can cause surging if it has a problem. That’s where I got that from.
I put gas line antifreeze in and filled the tank up, and drove for 5 miles. No CEL and no change in the surge every second.
Doesnt matter what speed, idle or anything. Every second, a slight surge/loss of power.
I guess I’ll have to bring it to the dealer on monday.
36k miles… change plugs and wires?
---
### Author:  [@Clean\_Baldy](https://forums.speedlife.net/u/Clean_Baldy)
#### Post date: [February 16, 2008, 10:20am UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/6 "2008-02-16T10:20:42Z")
> [@newman](#):
>
> how could you hear hesitation in the fuel delivery system?
Under the hood, that fuel delivery system next to the engine. I can hear the gas flowing through and right when the hesitation hits, the fuel going through also gets quieter. You can hear it.
---
### Author:  [@nitroinsane](https://forums.speedlife.net/u/nitroinsane)
#### Post date: [February 16, 2008, 10:28am UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/7 "2008-02-16T10:28:54Z")
> [@Clean Baldy](#):
>
> K. I was reading that a fuel pump can cause surging if it has a problem. That’s where I got that from.
>
> I put gas line antifreeze in and filled the tank up, and drove for 5 miles. No CEL and no change in the surge every second.
>
> Doesnt matter what speed, idle or anything. Every second, a slight surge/loss of power.
>
> I guess I’ll have to bring it to the dealer on monday.
>
> 36k miles… change plugs and wires?
you dont have wires. and you are not going to hear the fuel system. what u may hear if you have sonar hearing is the injectors turning on and off. you have a a bad miss fire. could be a injector plug or coil. i doubt its the fuel pump.
---
### Author:  [@Clean\_Baldy](https://forums.speedlife.net/u/Clean_Baldy)
#### Post date: [February 16, 2008, 10:33am UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/8 "2008-02-16T10:33:36Z")
Wow, I feel totally on the loop on cars now. No wires? LOL
So, sounds like a definite job for the dealership… bummer.
Thanks Joe 🙂
---
### Author:  [@nitroinsane](https://forums.speedlife.net/u/nitroinsane)
#### Post date: [February 16, 2008, 10:52am UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/9 "2008-02-16T10:52:54Z")
no u have a cop(coil on plug) car.
---
### Author:  [@somedude](https://forums.speedlife.net/u/somedude)
#### Post date: [February 16, 2008, 1:41pm UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/10 "2008-02-16T13:41:38Z")
pull your K&N air filter out and reinstall a paper filter clean your maf.
---
### Author:  [@somedude](https://forums.speedlife.net/u/somedude)
#### Post date: [February 16, 2008, 1:42pm UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/11 "2008-02-16T13:42:16Z")
> [@Clean Baldy](#):
>
> Wow, I feel totally on the loop on cars now. No wires? LOL
>
> **So, sounds like a definite job for the dealership… bummer.**
>
> Thanks Joe 🙂
WTF when did this turn into a audi forum?
---
### Author:  [@9ONA3OOZX](https://forums.speedlife.net/u/9ONA3OOZX)
#### Post date: [February 16, 2008, 1:44pm UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/12 "2008-02-16T13:44:50Z")
i had a fuel line leaking once a while back and it would cause hesitation in throttle response…but that’s not too likely in a newer car like yours.
and i dont know what the vacuum line setup is like in your car, but a vacuum leak would cause those symptoms too i would imagine…since i have vacuum leaks, and have similar/same symptoms…
---
### Author:  [@Clean\_Baldy](https://forums.speedlife.net/u/Clean_Baldy)
#### Post date: [February 16, 2008, 1:53pm UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/13 "2008-02-16T13:53:43Z")
I wish I could find an underhood diagram so I can check for a vacuum leak. Or, I wish I had one of those vacuum leak smoke tester things.
Anyone want to try and help me find a solution tomorrow(sunday)? Otherwise, I’m stuck bringing it to the stealership
---
### Author:  [@9ONA3OOZX](https://forums.speedlife.net/u/9ONA3OOZX)
#### Post date: [February 16, 2008, 1:59pm UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/14 "2008-02-16T13:59:14Z")
do you have a vacuum/boost gage? i’m sure somebody on here has an extra one…and it takes 2 seconds to just tap into a vacuum line to get a reading on it…just look online what the vacuum is supposed to be at at idle, and then observe what you have. if it’s low, there’s your first step to fixing the problem…and even if you dont have the time or capability of fixing it yourself, you at least saved yourself the money you’d spend at a dealer on diagnosis. just go there and tell them you have a vacuum leak, find it and fix it. otherwise they’ll run 2 or 3 hours worth of tests just to say “yup it’s a vacuum leak…that’ll be $250 for diagnosis…”
---
### Author:  [@Clean\_Baldy](https://forums.speedlife.net/u/Clean_Baldy)
#### Post date: [February 16, 2008, 2:15pm UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/15 "2008-02-16T14:15:12Z")
> [@90NA300ZX](#):
>
> do you have a vacuum/boost gage? i’m sure somebody on here has an extra one…and it takes 2 seconds to just tap into a vacuum line to get a reading on it…just look online what the vacuum is supposed to be at at idle, and then observe what you have. if it’s low, there’s your first step to fixing the problem…and even if you dont have the time or capability of fixing it yourself, you at least saved yourself the money you’d spend at a dealer on diagnosis. just go there and tell them you have a vacuum leak, find it and fix it. otherwise they’ll run 2 or 3 hours worth of tests just to say “yup it’s a vacuum leak…that’ll be $250 for diagnosis…”
I just went outside to do a thorough underhood look to see if anything was loose, how the MAF sensor looked, etc.
As I got back in the car to turn it on, the CEL stayed on. Now I wish I knew someone with a scanner!
---
### Author:  [@psychopjv](https://forums.speedlife.net/u/psychopjv)
#### Post date: [February 16, 2008, 3:05pm UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/16 "2008-02-16T15:05:32Z")
so you have a car with a warranty and are getting bent out of shape? Not trying to be rude or anything, but why frustrate yourself and everyone here when the dealership has the exact means necessary to diagnose this problem in an instant? If it is covered they have to fix it , plain and simple.
And Joe sounds about right, you have a wicked misfire somewhere. Don’t rule out the oiled up MAF though.
---
### Author:  [@Pauly](https://forums.speedlife.net/u/Pauly)
#### Post date: [February 16, 2008, 3:08pm UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/17 "2008-02-16T15:08:35Z")
Where you at?
---
### Author:  [@Nikuk](https://forums.speedlife.net/u/Nikuk)
#### Post date: [February 16, 2008, 3:31pm UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/18 "2008-02-16T15:31:21Z")
warranty & loaner car = FTW.
$0.02
---
### Author:  [@nitroinsane](https://forums.speedlife.net/u/nitroinsane)
#### Post date: [February 16, 2008, 3:33pm UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/19 "2008-02-16T15:33:41Z")
why scan it. its going to say cylinder misfire. you seriously should stop worrying and just take it over to mazda coils are covered plugs are cheap. just dont let them talk you into the unneeded tune up shit
---
### Author:  [@Nikuk](https://forums.speedlife.net/u/Nikuk)
#### Post date: [February 16, 2008, 3:35pm UTC](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546/20 "2008-02-16T15:35:40Z")
lol, because he apparently enjoys 20\* weather. :gotme:
[Next page](https://forums.speedlife.net/t/surging-rpms-any-insight-please/43546.md?page=2)