finally got fuel cut

Jessed87

Member
well as the title says, I finally witnessed fuel cut on my car. I am running stage 1 cobb with v103 93 octane map. I cut in fourth gear around 5 thousand RPMs. I am buying the fuel pump internals tonight so I have a question for all of you who have done this already. I only have the COBB AP and I cannot find a way to read fuel pressure on it. Do I have to buy a dashhawk to read fuel pressure? I will be buying one eventually but I really cant afford it at the moment. Does anybody know if there is a way to read fuel pressure on the AP?
 
You should be able to view fuel pressure it's one of the parameters available on the AP. The software on yours might be old and you may need to update it.
 
hmm...does anyone know where I can find the latest firmware update? anyone else know for sure if it will work?
 
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Don't assume your cut is FP. Everyone just seems to want to jump on the FP everytime their car stutters. Seeing as you're running Stage 1 I assume that you have nothing for mods really. If that is the case then it's pretty much no way your FP could be maxed out yet. No way at all. I'm just now hitting fuel issues with all my mods and mine only dips to 1300.

Not to say internals are not a good mod, just saying that your money is better spent on other mods and finding the real issue of the cut.
 
^^
+1

Since the OP has the AP, he really should be logging and taking a look at his fuel pressure logs while at WOT. I know I have and judging by the #s, my stock FP is perfectly adequate with the mods that I have running Stage1+ v103 but I still get the occasional BOOST cut. I'm not 100% certain the OP is really experience fuel cut.
 
Do the mods and run the parts Cobb recommends for using the ap and you will be fine.

ONLY if you plan to run their OTS maps. Otherwise, with ATR just around the corner, you can pretty much run anything you want so long as you have access to get it dyno-tuned professionally.

Considering the amount of variability of results with the OTS maps, I think it would be highly beneficial for most AP owners to get their MS3 dyno-tuned. Personally, I can't wait to get mine tuned.
 
Well what might the other reason for cut be? I am running the exact mods that COBB says to run, and the correct fuel. I am not getting boost spikes or boost creep. Everything pulls perfect with no stutter, and all of a sudden it was like someone slammed on my brake pedal. I have done countless and I do mean countless pulls in 1st through 4th and have never even gotten a stutter until the cut I just got. I'm not sure how to datalog, I think I need newer firmware. I'm not sure what the issue could be but just running stage one boost hits 18 PSI which is only one pound below stage 2. I don't think that the amount of fuel being used is too far different. Also being an early 07 model I am willing to bet my fuel pump is one of the crappier ones. If anyone has any other specific suggestions or reasons to believe otherwise, please feel free to share. At this point my only course of action is a fuel pump rebuild, being as that it is the only thing that I can really do besides going back to lower boost tunes. Also unless Ive really lost it, COBB's website does not appear to have the latest firmware updates, only the newest maps and accessport manager software. Any info would be helpful.
 
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We're only trying to save you $$ but if you THINK a FP rebuild will solve your issues then let us know how it goes. Until you log some #s and research into this, you're just shooting in the dark. Just throwing money and parts at it won't necessarily solve your problems.

What you're most likely getting is boost cut, it is a safeguard built into the ECU and Cobb has not removed it. What they did, according to them, was simply raise this limit so it is still possible to get it even when running one of their maps. But I could be wrong and it could be that your stock FP is taking a dump on you but you'll have no idea until you start logging.

If your AP doesn't have the logging function then you need to flash it with the newest firmware. I got the AP not too long after it came out and at the time, it could not datalog. I clearly remember getting the AP firmware from the Cobb website. Look harder.
 
FP issue is not a slam on the brake feel man. That is a boost cut issue. FP issue is like running out of gas and is a stutter or hesitation not a slam on the brakes.

Datalog first. Cobb firm update info is here http://www.cobbtuning.com/info/?ID=4106

Do some datalogging first before you jump to buy a FP. There is NO REASON, ZERO, for you to have FP issues due to your mods. The only way is for your FP to be bad due to the 2007 Recall.

The way to tell is to capture some logs and if your FP drops below 1400 (Mine before I got the TSB done would drop to 900psi), then print out the log and take it to Mazda as proof that your FP needs to be updated. Then insist on the FP replacement as the PCM update will just be nixed by your AP flash. Also the pump solenoid is the issue on the bad pumps and if you have a bad one even the FP internals will not help you as it is the solenoid.
 
Thank you guys, those were exactly the posts I was looking for. I realize that the fuel pump may not fix it, but I would like to have it before I go stage 2 anyway before I put my downpipe on so don't worry it's not wasted money. As for the link to the new firmware, thank you I appreciate it! I will begin data logging as of tommorrow and see if I can find an answer for sure. Thanks again for the help guys.
 
Lots of people still get cut with the AP. Thats why i didnt get it. I agree with little to no mods, you dont need a FP.
 
I'm experiencing some cut on some but not all pulls 1-4 gears. I'm hoping colder plugs will solve this. Opinions?
 
I'm experiencing some cut on some but not all pulls 1-4 gears. I'm hoping colder plugs will solve this. Opinions?

Plugs dont cause cut. If you feel a sputter/hesitatation that is when you need plugs. The most common reasons for cut on this car are....too much boost, colt temps or acombination of the 2.
 
I agree, I had a shutter the mid rpms and one step colder plugs solved it. No fuel cut yet. Knock on Wood... "Stage1+MSCAI2 93 v103"
 
Probably too much boost for me. Logged 21.0 and that's probably too high to go without getting cut. I suppose there is no quick fix for that.
 
I agree, I had a shutter the mid rpms and one step colder plugs solved it. No fuel cut yet. Knock on Wood... "Stage1+MSCAI2 93 v103"

I have read about others getting rid of that lag by using colder plugs. I think I mightl give it a shot. How often are the new colder plugs supposed to be changed?
 
I have read about others getting rid of that lag by using colder plugs. I think I mightl give it a shot. How often are the new colder plugs supposed to be changed?

I don't know what the specific manufacturers suggest, but Cobb recommends changing them every 15k miles.
 
Plugs dont cause cut. If you feel a sputter/hesitatation that is when you need plugs. The most common reasons for cut on this car are....too much boost, colt temps or acombination of the 2.

+1

One step colder plugs may help but it is not the entire solution. I have the Denso ITV-22s and I still get boost cut on occasion. But TBH, I'm not certain it's the plugs that are helping as the weather has been warmer now that it's spring. The real test will be when winter rolls around again but by then, I hope to be dyno-tuned with the help of ATR.
 
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