KR, Negative LTFT, Low Boost

Rustyms3

Rustyms3

Greenie N00B Member
Okay I'm starting a new thread becuase I've learned alot since I first got my hatchback. I have a 2007 mazdaspeed 3. It has a no name Sri with straightener, Autotech internals, just did a fuel pump seal kit, a tubular header, aluminum flywheel, reproduction factory turbo, egr delete, deleted second cat, and a V3 Accessport. Alot of the parts were on the car when i purchased it. Just replaced the spark plugs with factory densos gapped at .27. I have no history over this car other than the engine is under 50k miles old. I've had an on-going issue. I've learned more details over about 6 months of dead ends. Basically I'm having knock conditions with no correlation to any other values except for rpm . I get KR upwards of 8 degrees above 5k. The car falls on its face at 5k. At idle my LTFT are around -11 to -14 although normal (-.16)under any load. It will not spike above 14psi no matter the tune. My data logs seem that it hates anything close to 10 degrees advanced ignition timing around 5k at 13psi. Id like to also mention my second oil change (around 3700mi) came with a golden stream of metallic flakes. I since changed it early at 2k and little to no flakes were present. It has a small audible miss fire at idle. The tubular manifold warms up consistently on each runner. Im almost scared to do a comp test. The engine pulls very very well until 5k. This is supposed to be my college car and fall is just around the corner. I will be 4 hours away from my shop and tools. I'd love to get this fixed anyway possible. Im running the only 91 octane fuel that is even remotely close to me (another 91 pump is an hour away).
These data logs are on COBB OTS Stage 1 plus SF map for 91 octane.
 

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Rustyms3 said:
Okay I'm starting a new thread becuase I've learned alot since I first got my hatchback. I have a 2007 mazdaspeed 3. It has a no name Sri with straightener, Autotech internals, just did a fuel pump seal kit, a tubular header, aluminum flywheel, reproduction factory turbo, egr delete, deleted second cat, and a V3 Accessport. Alot of the parts were on the car when i purchased it. Just replaced the spark plugs with factory densos gapped at .27. I have no history over this car other than the engine is under 50k miles old. I've had an on-going issue. I've learned more details over about 6 months of dead ends. Basically I'm having knock conditions with no correlation to any other values except for rpm . I get KR upwards of 8 degrees above 5k. The car falls on its face at 5k. At idle my LTFT are around -11 to -14 although normal (-.16)under any load. It will not spike above 14psi no matter the tune. My data logs seem that it hates anything close to 10 degrees advanced ignition timing around 5k at 13psi. Id like to also mention my second oil change (around 3700mi) came with a golden stream of metallic flakes. I since changed it early at 2k and little to no flakes were present. It has a small audible miss fire at idle. The tubular manifold warms up consistently on each runner. Im almost scared to do a comp test. The engine pulls very very well until 5k. This is supposed to be my college car and fall is just around the corner. I will be 4 hours away from my shop and tools. I'd love to get this fixed anyway possible. Im running the only 91 octane fuel that is even remotely close to me (another 91 pump is an hour away).
These data logs are on COBB OTS Stage 1 plus SF map for 91 octane.
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- Assuming there is no mechanical problems with your car: Your STFT/LTFT are far from zero because you need to calibrate the MAF sensor to your intake. The COBB OTS is calibrated for their SF intake.
- If you are using OTS tune, your WOT runs are running very rich. If your sensors are in order, it means that the ECU is reverting to the last resort it has for fueling "Max Enrichment allowed" table, which is around 10.5AFR. Seems like your runs are ALWAYS in this region. As there are no signs of knock when it goes this rich, I don't see why it would be going to this table. Fuel trims will not be used in Open loop (I.e. WOT). You need a MAF calibration to start!
- COBB OTS maps use Boost based tuning. It looks like your intake and Boost temperatures are relatively high. Physically speaking, this type of tuning finds its limitation with temperature and altitude. Meaning, higher temperatures will result in lower boost pressures for the same wastegate duty cycles - simple solution is to turn up the duty cycles, just remember that when it gets cold, you may be over-boosting. There are also tables to allow the ECU to manage the wastegate error based on temperature or amount of error.
- Finally, the high temperatures may have the ECU use values programmed for high temperatures, which are normally more conservative.

Throw on the OEM intake with COBB OTS stage0 tune and log again.
 
Considering how weird everything is it may be worthwhile to try running off spring pressure. You'll get to see what spring rate your IWG is at and also see if the knock you consistently get at 5.5k dissipates.

You should be running at least a compression test. All of this is for naught if your engine isn't healthy anyway.
 
I've also noticed the high temps. My engine is missing the top cover that goes around the intercooler so I think the air is going around rather than through the intercooler. It will heat soak on a sunny day as much as 130-140 at cruise. I've thought mabye a very small methonal jet could help with those extremes but I dont want to rely on it. I dont have the factory intake but im sure I could get one somewhere. This kind of engine management is very different than im used to. I will look up how to calibrate the MAF, get a shroud made for the intercooler and disconnect the boost controller. I'll log once more and see if the issue persists. I appreciate everyone for the input.
 
broda said:
Considering how weird everything is it may be worthwhile to try running off spring pressure. You'll get to see what spring rate your IWG is at and also see if the knock you consistently get at 5.5k dissipates.

You should be running at least a compression test. All of this is for naught if your engine isn't healthy anyway.
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I just preformed a compressions test. Bone cold, 5 revolutions. Counting from the drivers side
cylinder 1 175
Cylinder 2 135
Cylinder 3 175
Cylinder 4 160.
I definitely don't like the 135 but thats not enough to cuase these issues right?
 
Rustyms3 said:
I just preformed a compressions test. Bone cold, 5 revolutions. Counting from the drivers side
cylinder 1 175
Cylinder 2 135
Cylinder 3 175
Cylinder 4 160.
I definitely don't like the 135 but thats not enough to cuase these issues right?
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That's outside of spec even from Mazda. Their max difference is 28.5 psi between cylinders on top of 130 psi being the minimum which it's almost at. Try doing a wet test on the #2 cylinder and see if your reading increases substantially. If it increases then your rings are bad.

Starting at the driver's side, that's actually the #3 cylinder which is the one that notoriously goes bad.
 
broda said:
That's outside of spec even from Mazda. Their max difference is 28.5 psi between cylinders on top of 130 psi being the minimum which it's almost at. Try doing a wet test on the #2 cylinder and see if your reading increases substantially. If it increases then your rings are bad.

Starting at the driver's side, that's actually the #3 cylinder which is the one that notoriously goes bad.
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I put a little bit of auto trans fluid and repeated the test on that cylinder. It now shows 160psi. Im sure the knock issue has played a part in this. It doesn't loose any oil what so ever so it could be just the top rings right? No matter what I have to get rid of the knock issue before anything else is done. It won't make any sense to throw my money into building a motor and still have knock at fairly stock power levels.
 
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The most likely cause is a bad injector. Pulling them and getting serviced would be advisable and it's generally good practice for this platform anyway. Unless if you know your injectors are good then personally I wouldn't do more WOT pulls with the amount of knock you're seeing until they're serviced. Gonna have a lot worse of a time if you vent your block trying to troubleshoot further.

Also, with you seeing gold flakes in your oil I'm wondering if you spun a bearing.
 
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A leaking injector would cuase the negative fuel trims at idle. I have no idea how healthy the injectors are. So ill be pulling them before any more damage is done. I'll get back to yall with anything I find. Thank yall.
 
I pulled the injectors. They look pretty nasty. The intake valves aren't any better either. Anyone know anything about a company called AUS injection? They offer a full DI injector service for 25 bucks a peice. New orings, cleaning, and flow matching.
 
Rustyms3 said:
I pulled the injectors. They look pretty nasty. The intake valves aren't any better either. Anyone know anything about a company called AUS injection? They offer a full DI injector service for 25 bucks a peice. New orings, cleaning, and flow matching.
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not many of us are in aus...reading their website sounds like that's exactly what you're after I'd go for it.
 
Haven't heard of them before but at a glance they look pretty solid. People generally recommend Injector Rx but if the other place is somewhat local to you then it'll make your turnaround time faster.
 
Awafrican said:
not many of us are in aus...reading their website sounds like that's exactly what you're after I'd go for it.
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At first I thought AUS meant Australia too. Their actual based in Tempe Arizona. Not local to me as I'm from oklahoma but at least there in the US. I think ill give them a shot.
 
Rustyms3 said:
At first I thought AUS meant Australia too. Their actual based in Tempe Arizona. Not local to me as I'm from oklahoma but at least there in the US. I think ill give them a shot.
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If you're looking to ship out within USA I'd go with Injector RX, otherwise try find a local shop that can do it
 
Awafrican said:
If you're looking to ship out within USA I'd go with Injector RX, otherwise try find a local shop that can do it
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Just got my injectors back they weren't that bad. Injector rx really screwed one of them up with a vice or pliers. (Not to happy about that) Instaled some rockauto seals and put it back together last night. The car wouldn't start. I read that the high pressure system takes a bit of cranking to get fuel back in. I cranked on it long enough and gave up. I've checked everything, got codes off my ap. Nothing other than a high voltage tps but I think thats becuase I had the throttle wide open. I got in it again today after work and it start after 10 seconds or so of cranking. It runs in the mid to high 20s afrs. At first it sounded like only one injector was firing but now it sounds like 2 or 3 are. I did deleted the vtcs system, gave it a nice smoothing and polish and plugged the holes well. No vaccum leaks I could hear/see. Brake clean doesn't find anything either. I got a data log and will upload later if that would help at all. The hpfp is making upwards of 1300psi so I wouldn't suspect it has any air in it still. Once again this car has me stumped. It seems I make more problems than I fix.
 
I just went back out and it ran normally for a few seconds and then went back to runnign stupid lean. Im getting the normal codes of egr vtcs stuck abs code. i do have one "injector cyl 4 eletrical malfunction" so im guessing its with that injector. still wouldnt explain running normaly then running like garbage. heres the data log
 

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Awafrican said:
Thanks was just about to link this...man that sucked turns out was just a bent pin on the Injector I'd start there and Inspect the connector. Pics are in the thread
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It was just a loose connector on the injector. The car is running pretty well actually. I cant say if its fixed the knock issue as I've seen some knock but not as much. I know the ecu pokes and prods to find the balance between gas mileage and throwing a rod so I figure hitting 2 degrees every once and while is better than hitting 6 or 7.
 
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