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Discussion Starter #1
So for a while now (not sure how long), my car has been idling weird. Before installing my AP and using ATR to modify my idle, my idle was rough and seemed low. Now upon installing the AP and reflashing the modified stock map, I have noticed an issue. I set the idle at 900 for table a, and 950 for table b as I have read in a previous thread.

My issue comes in when I have the warmed the car up and am sitting still idling. I have the A/C off currently - as it is not working properly - so you would think it would idle at 900. Turns out it idles more than 1000 rpm. However, when examining the APs rpm data, it says more like 950. Now I don't know if the AP monitors idle differently than the speedo, but its definitely off. And I know the AP is no DH, but they should monitor the rpms in the same way, right?

I have a few other problems that need to be worked out, such as the A/C, but one at a time for now. But my question is: Is this normal? Should the speedo appear to be idling at 1000 when it is actually at 950 according to AP? Shouldn't I be idling at the 900 I set it for? I have included a video that will show my new found discovery. Any advice is appreciated.


Thanks


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check ur fuel trims and AFR. Akso might want to look into changing ur plugs.
 

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Discussion Starter #3
Afr is right around 14.7, where it should be. And plugs were just changed 1000 miles ago.
 

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I know the variance between the AP and the tach is normal, with the AP or other loggers likely being more accurate. As far as the varience between your goal of 900 and the monitored 950, perhaps there's other conditions which may create discord between your targets and what's seen on the AP.
 

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Discussion Starter #5 (Edited)
I had +20% LTFTs (most likely a leak somewhere) and +5% STFTs at one time but not sure where they are at now. Would that possibly be a reason for this? I know a leak test is on my agenda, if I knew where to get a smoke test done, but I just wanted to know for sure if this was normal or not
 

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I had +20% LTFTs (most likely a leak somewhere) and +5% STFTs at one time but not sure where they are at now. Would that possibly be a reason for this? I know a leak test is on my agenda, if I knew where to get a smoke test done, but I just wanted to know for sure is

i had a cracked stock BOV that was causing my MS6 to do the same... i also threw a cel with this issue though so my not be same problem.:confused:
 

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I had +20% LTFTs (most likely a leak somewhere) and +5% STFTs at one time but not sure where they are at now. Would that possibly be a reason for this? I know a leak test is on my agenda, if I knew where to get a smoke test done, but I just wanted to know for sure if this was normal or not
If you had a bad leak, you ECU would be pulling fuel, as less air is making it to the throttle body than has passed over the MAF (then the ECU "sees" less air is actually coming in, so it pulls it). So, large negative LTFT's would be indicative of leak, not +20. +20 is horrible though... have they always been that high? At at what MAF voltages....is it just at idle? Read step 2 of the help file about calibrating your MAF, and do the MAF g/s test as described. That will show us what your LTFT's are throughout the MAF range (0-5 volts). There's 5 breakpoints. Is the +20 only at idle? I don't think that difference in idle is nearly as big of a deal as your LTFT's. Also, a "higher" idle indicates a higher load. With your FT's that whacky, it's hard to know what's going on. That might be your whole problem. Make sure to leave the A/C off when you're doing the MAF g/s test for consistency.

Is your air filter filthy? Perhaps your MAF sensor got really dirty. Do you have a CAI or SRI? What other mods do you have?
 

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No..wouldn't air leak be adding more fuel? Because it's adding more air into the engine than the maf can see..so it needs to add fuel to compensate?

lol.. Atleast that's what I remember when I forgot plug in the BOV hose.
 

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No..wouldn't air leak be adding more fuel? Because it's adding more air into the engine than the maf can see..so it needs to add fuel to compensate?

lol.. Atleast that's what I remember when I forgot plug in the BOV hose.
Well, it depends on where it is and what's going on. If he's loosing air (through a boost leak), then it will be pulling fuel. I assumed OP was talking about a boost leak. I had a vacuum leak in my TIP that was causing air to both leak OUT, and get sucked IN, depending on how the tear was getting torqued with engine movement, throttle position, etc. I know it was doing both from my WOT afrs. however, at idle, my FT's were close to zero. It was only under force (accelerating), that the tear would be opening and closing.

You're absolutely right in that if unmetered air is coming IN, then the ECU will be adding fuel. However, if OP is getting LTFT's of +20 at idle, something is screwing here. You're intake is sucking in much air at idle, so even if he had a leak, I doubt it would be causing his LTFT's to be +20. It sounds like his MAF is really dirty, and it's not picking up all the air that's passing over it. That or is MAF calibration is way off (or both). I dunno. I don't know when he's getting LTFT's of +20 (OP, idle??), or what his FT's are doing at other MAF voltages, why he thinks he has a leak, etc. We need more info from the OP, and he needs to take some datalogs.
 

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Discussion Starter #10 (Edited)
I can do some logs if that will help. Should I just log the default AP data?

My LTFTs are only that bad at idle. I do have a boost issue as well, possibly a boost leak, i'm not sure. I'm not accustomed to turbo vehicles and throughout the two years I have owned this car, I am still learning new things.

As far as mods, very minor stuff. I had done an egr delete, vcts delete, occ, ptp hpfp, ptp im gasket, and ap stock flash. I had a cobb intake at one point, but I sold it... But idk how long this issue has been happening because I just noticed the idle after I did the AP stock reflash. My idle/LTFTs might have been off stock, I just wasn't able to capture this in a log before I did the flash.

Also air filter is perfectly clean and I had done a MAF cleaning not too long ago, after I put in my IM gasket around 7000 miles ago, this past February.
 

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I had an issue this past week where my ilde would bounce and drop low (esp with AC on) when stopping. Doing some research I noticed the TSB about a dirty TB. I decided to clean the MAP first, which didnt help. I then took off the TB to clean it (which wasnt that dirty) and noticed the vaccume hose to my BOV was not on all the way. After the reinstall of everything the issue went away. Im sure this isnt you're issue, but with me it seemed to be vaccume related.
 

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If you have +20 LTFT at idle, then it's a leak.. A leak.. Boost/Vacuum leak.

Check your hoses! Especially whatever you touched.
 

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The only way you will lose air to the engine post maf is if you are in boost. If you have +20LTFT at idle like ktan says its a vacuum leak somewhere and air is being pulled in. one common place is the stock pcv.
 

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Discussion Starter #14
So just an update on my problem. I was searching around for leaks this afternoon on my car. I installed my occ kit a while ago and I guess I didn't read the manual thoroughly enough. I thought the drain on the bottom was sealed when it was screwed in all the way. And for a while now I have been wondering why I have no oil ever emptying out of the catch can. Well I had it screwed in all the way, essentially creating an enormous vacuum leak. This would explain my idle issue to an extent, not including other issues I have yet to figure out.
 
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