Fuel Pressure Dips

[RichieRichness]

surebOOst should also try this as he is having the same issue.

[surebOOst]

Definetely going to try this!

[Schmitty5]

Just tried this, did not work. Pushed the pins delicately, but firmly. Connected and disconnected it 3 or 4 times. Sprayed it with MAF cleaner 3 or 4 times. Let it dry, reset battery. Nothing.

My last hope is the itfp which is a bitch to get out.

I'm getting serious knock now and AFRs are way unstable. fuck.

This all started after a couple tanks of e85 mix. coincidence?

Notice how the hpfp voltage is now correlating with the fuel pressure drops, just about everytime now

[RichieRichness]

damn Paul that shit is getting much worse.

[Schmitty5]

[Nataphen]

You've cleaned the spill valve and checked for black death I presume.

[surebOOst]

?

[RichieRichness]

Originally Posted by surebOOst ?

your not running e85 so it's less likely that you are having an issue with "black death" aka gunk and grime buildup.

Schmitty5 maybe it's time to go back to your stock HPFP and see if that makes any change.

[Schmitty5]

Originally Posted by Nataphen You've cleaned the spill valve and checked for black death I presume.

Yes I took my fp completely apart and it was black as fuck. cleaned it and haven't gone back to e85 since.

[StayBroke]

atvfreek, mine hpfp dipped from 1700 to 561 back to 1734, so it only had the low 561 in one cell.

Also did another log and it did the same thing but hit 192 in one cell.

I have not tried the plug but would you say that would fix? trying it in a little bit but dang i really dont want to buy another hpfp internals.

[G26]

Originally Posted by StayBroke atvfreek, mine hpfp dipped from 1700 to 561 back to 1734, so it only had the low 561 in one cell. Also did another log and it did the same thing but hit 192 in one cell. I have not tried the plug but would you say that would fix? trying it in a little bit but dang i really dont want to buy another hpfp internals.

Dano had the same problem, I think it was caused by the sensor loosing a good connection.

[Oliverms3]

its most likely the plug. I had the same problem, which i mentioned on the first page. Just make sure that plug is secure and clean, the problem should go away.

[Schmitty5]

Yea, if you can't get it to go away fuck it.

I went to an e85 mix after weeks, shit, months of this problem (on 93) right before I took it do the drag strip. I swapped pumps, hpfp fuel rail sensors, cleaned the pump TWICE. reinstalled AP, played with the fuel sensor attachment pins, I've done everything. The e85 somehow got rid of the problem for a few logs, but now its back, its so damn finicky.

As long as your car FEELS ok, I really wouldn't worry too bad. I've tried EVERYTHING, and it won't go away for more than a couple logs here and there. Just keep monitoring it and speak with your tuner and have him adjust things if needed. But don't worry you too much like I did.

[atvfreek]

Originally Posted by StayBroke atvfreek, mine hpfp dipped from 1700 to 561 back to 1734, so it only had the low 561 in one cell. Also did another log and it did the same thing but hit 192 in one cell. I have not tried the plug but would you say that would fix? trying it in a little bit but dang i really dont want to buy another hpfp internals.

It's definitely not your internals if it's only one cell. Some guys just disconnected the fuel rail pressure sensor and plugged it back in and it was fine. On mine I had to physically squish the pins in the connector to make them smaller. And shmitty has had no luck what so ever.

I would try the disconnecting the connector first.

[G26]

Yeah, i would say for the internals to cause a drop that drastic in pressure that quickly, they would have to completely seize, and the end result of that would be catastrophic failure.

[Nataphen]

I've never seen OP's drop for more than one cell at a time either. It's definitely got to be sensor related, and as long as your car doesn't do anything to counter it, I'd say fuck it. HPFP issues would result in a more sustained drop. He has never reported that his car felt badly on these logs, so I just told him to be careful and we carried on. We tried all the fixes, but his still does it from time to time.

[StayBroke]

Here is mine, still no luck.

[jeopardy98]

Okay so rfinkle2 dialed back a little timing and a tad bit of boost to get rid of some KR and my first log after I have this issue. Never ever had the issue before today that I have caught in a log. VD also netted the pull at 6 more whp than I dynoed bone stock. Granted it was 85 degrees but still. Hmmm something is strange here. Thoughts?

[rfinkle2]

atvfreek has a solution that works in some cases. I'll let him chime in.

Originally Posted by jeopardy98 Okay so rfinkle2 dialed back a little timing and a tad bit of boost to get rid of some KR and my first log after I have this issue. Never ever had the issue before today that I have caught in a log. VD also netted the pull at 6 more whp than I dynoed bone stock. Granted it was 85 degrees but still. Hmmm something is strange here. Thoughts?

Didn't you actually dyno the car and pretty much eclipse your old numbers?

If you truly feel that the car was as powerful bone stock, by all means, use the stock map.

[jeopardy98]

Originally Posted by rfinkle2 atvfreek has a solution that works in some cases. I'll let him chime in. Didn't you actually dyno the car and pretty much eclipse your old numbers? If you truly feel that the car was as powerful bone stock, by all means, use the stock map.

No way man, that isn't what I meant at all. You have been amazing and I know the car is making power. I just was utterly confused by it all. Sorry if it seemed like I was knocking on you. I was just looking for some guidance/reassurance/explanations. Thanks again for everything.

[SLOWHATCH]

Damn jeopardy98 I think your bat's are killing your numbers. VD is a good estimator of HP but not always accurate IMO. I still get VD's that show I'm only making like 311 hp but most of the time they are on point. I wouldn't let one graph make your mind up about the hp you are making.

Aside from the high bat's everything else looks good IMO.

[rfinkle2]

Originally Posted by jeopardy98 No way man, that isn't what I meant at all. You have been amazing and I know the car is making power. I just was utterly confused by it all. Sorry if it seemed like I was knocking on you. I was just looking for some guidance/reassurance/explanations. Thanks again for everything.

The truth is, there are some guys experiencing this one cell phenomenon, and I have personally spent hours looking through threads looking for a solution / cause, and have been in close communication with staybroke concerning the issue.

Staybroke has talked to Pt-performance about it, and before anyone goes apeshit about John, trust me when I tell you, he has done a lot of research on the fueling for our car (possibly the MOST research on the internals / sensors / fuel rail and injectors), and he is stumped (for now) as well.

I can tell you this... I see no KR, barely a change in afr that would be alarming, and until we can put our heads together or somehow come up with a permanent solution, I would continue to drive the car the same way you did before the issue arose.

As for the VD numbers, you aren't comparing apples to apples when you are stating that you are now 6hp over the stock map. In order to compare the map that I made you to the stock map, you would have to load it, do a 4th gear log and load that into VD, and compare the VD #'s to VD #'s.

I don't know man, I apologize for seeming pissy, but it just seems everyone is quick to post there unresolved issues as if any one of the guys tuning Mazdaspeeds wouldn't fix it for you if there was a known solution to the problem.

[atvfreek]

Originally Posted by jeopardy98 Okay so rfinkle2 dialed back a little timing and a tad bit of boost to get rid of some KR and my first log after I have this issue. Never ever had the issue before today that I have caught in a log. VD also netted the pull at 6 more whp than I dynoed bone stock. Granted it was 85 degrees but still. Hmmm something is strange here. Thoughts?

What year is your car? Sorry can't see sigs.

I have mostly seen this issues in the 2010's and seems like it is certainly a connection issue. I would disconnect all your connectors that the fuel pressure sensor wiring goes through and clean them all with electrical contact cleaner. I also squeezed the pins together slightly at the FRP sensor and it worked for me. Some people haven't had as good of luck. The good news is that its not an actual pressure issue.



Freekn tappin

[jeopardy98]

Originally Posted by rfinkle2 The truth is, there are some guys experiencing this one cell phenomenon, and I have personally spent hours looking through threads looking for a solution / cause, and have been in close communication with staybroke concerning the issue. Staybroke has talked to Pt-performance about it, and before anyone goes apeshit about John, trust me when I tell you, he has done a lot of research on the fueling for our car (possibly the MOST research on the internals / sensors / fuel rail and injectors), and he is stumped (for now) as well. I can tell you this... I see no KR, barely a change in afr that would be alarming, and until we can put our heads together or somehow come up with a permanent solution, I would continue to drive the car the same way you did before the issue arose. As for the VD numbers, you aren't comparing apples to apples when you are stating that you are now 6hp over the stock map. In order to compare the map that I made you to the stock map, you would have to load it, do a 4th gear log and load that into VD, and compare the VD #'s to VD #'s. I don't know man, I apologize for seeming pissy, but it just seems everyone is quick to post there unresolved issues as if any one of the guys tuning Mazdaspeeds wouldn't fix it for you if there was a known solution to the problem.

No worries man. I just want to make sure you realize I'm nothing but happy with what you have done.

Originally Posted by atvfreek What year is your car? Sorry can't see sigs. I have mostly seen this issues in the 2010's and seems like it is certainly a connection issue. I would disconnect all your connectors that the fuel pressure sensor wiring goes through and clean them all with electrical contact cleaner. I also squeezed the pins together slightly at the FRP sensor and it worked for me. Some people haven't had as good of luck. The good news is that its not an actual pressure issue. Freekn tappin

It's a 2012 with only 6,000 miles on it. I'll give the connector a shot and if it doesn't work I'll just keep driving it and keeping an eye on it. I figured the one cell wasn't accounting for true fp drop. Thanks everyone.

[Schmitty5]

Really? You too now? Fuck the gen2 ecus

[RichieRichness]

We have another member to the fuel pressure dip club. gooch x1
4th gear WOT pull1 6-4-12.csv

4th gear WOT pull2 6-4-12.csv

4th gear WOT pull3 6-4-12.csv
Ron Wood v1.07.ptm

[StayBroke]

my god...when i get my ap back friday and it still is doing this, i give the hell up.

[StayBroke]

atvfreek....Look i did the connector again and used contact cleaner....idk what to do now.

Any thoughts?

[RichieRichness]

For tuning about 10 gen 2 MS3's this year I've seen this issue on 3 of them. There must be lots more people out there having this issue and not even know it.

[kabobulate]

I had this issue in my 2008. Pulling the sensor and plugging it back in would work for weeks or months and then it would come back. Dano was working through it at the same time I was and I was following a thread he had. I noticed that whenever his would come back, mine would at right about the same time. I had a theory that a large enough change in weather would trigger it, but that was just a theory.

[jeopardy98]

I've only got 6,000 miles on my car and I noticed start up as soon as the weather got hot and the humidity rose. We could be on to something?

[BT2010speed]

This might seem like an aweful question, especially with the serious FP dips that some are seeing... but this thread got me to look at a few logs... and i noticed that in a few cells i hit 1540 at the lowest for fuelpressure when at WOT.... now i know thats still pretty safe obviously and its only in single cells and only in like 5 on a recent pull but...i was just wondering if from time to time its normal to see fp dips like that even with upgraded internals...i have KMD internals as well. Should be concerned or is this normal... ive never really payed that much attention to it before until well after the internal install. im about to go fully bolted for the most part this week so i want to be sure everything is still pretty safe?

[rfinkle2]

Originally Posted by BT2010speed This might seem like an aweful question, especially with the serious FP dips that some are seeing... but this thread got me to look at a few logs... and i noticed that in a few cells i hit 1540 at the lowest for fuelpressure when at WOT.... now i know thats still pretty safe obviously and its only in single cells and only in like 5 on a recent pull but...i was just wondering if from time to time its normal to see fp dips like that even with upgraded internals...i have KMD internals as well. Should be concerned or is this normal... ive never really payed that much attention to it before until well after the internal install. im about to go fully bolted for the most part this week so i want to be sure everything is still pretty safe?

IMO, this is a single cell anolomoly vs a true pressure drop. Can you post the log?

Also, I don't think that I would let a situation like this go, but I also don't think that your car is in immediate danger.

Usually, when the FP fails, the car just goes rich.

[RichieRichness]

Originally Posted by BT2010speed This might seem like an aweful question, especially with the serious FP dips that some are seeing... but this thread got me to look at a few logs... and i noticed that in a few cells i hit 1540 at the lowest for fuelpressure when at WOT.... now i know thats still pretty safe obviously and its only in single cells and only in like 5 on a recent pull but...i was just wondering if from time to time its normal to see fp dips like that even with upgraded internals...i have KMD internals as well. Should be concerned or is this normal... ive never really payed that much attention to it before until well after the internal install. im about to go fully bolted for the most part this week so i want to be sure everything is still pretty safe?

As long as your AFR's are pretty stable there is nothing to worrie about. People with this fuel pressure drop issue tend to see their AFR's bounch around a bit.

[StayBroke]

Originally Posted by rfinkle2 IMO, this is a single cell anolomoly vs a true pressure drop. Can you post the log? Also, I don't think that I would let a situation like this go, but I also don't think that your car is in immediate danger. Usually, when the FP fails, the car just goes rich.

Maybe when i get the autotechs in i that my sensor will behave for me....yea right lol

[atvfreek]

Originally Posted by StayBroke Maybe when i get the autotechs in i that my sensor will behave for me....yea right lol

This is an absolute shot in the dark, but when I was fucking with my sensor and connections, I also threw in a bottle of chevron fuel injection cleaner. Somewhere between messing with all that shit, the fuel injection and lots of beer, mine fixed itself and hasn't been back.

[StayBroke]

well shall see.

[melbaro]

Sorry to necro this thread, but have there been any developments here?

[jeopardy98]

I have not noticed the issue since it started for me. The last few logs have been clear but the general consensus is that if it is one cell than it is an error with the log and not a mechanical fuel issue. It is possible that Cobb changed something in one of the last updates that solved the issue.

[kabobulate]

CruZ_MS6; developed the same problem a few months ago and was replacing all types of stuff trying to figure it out. Since I had the same problem on my gen1 I told him to pull the sensor and plug it back in again which always helped me. He would have to verify it is still good, but the last time I talked to him about it he said that it fixed the problem.