Rough few minutes after sitting
02-25-2017, 09:49 PM
#1
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Rough few minutes after sitting
Hi All and am looking for a little help but also still researching. My 1.8 T after sitting for a few hours idles fair as it inches up to correct RPM ( a light throttle play) BUT, any if I give it throttle to get moving there is a sputtering, roughness in the peddle and not much power. This lasts past the WUE as I lowered WUE to 145 degrees. o2 registers in high teens so I tried open loop but no help. Then all of a sudden o2 starts reading right in lower teens and the car drives like the amazing beast she is. What am I missing? Is she not happy until she is 190+ degrees? Am I burning off oil (no smoke but soot on drive way). There is backfire when i let off the throttle sometimes during this rough phase.
Any advice will be very welcome. I am starting to review logs but i see the limit of the free tuner viewer so I gotta upgrade.
1994 MX-3 BPT
I was on the BPT with New Zealand ECU since 2004, but after having a few electrical parts starting to fail i figred I would go with MS - microsquirt.
Any advice will be very welcome. I am starting to review logs but i see the limit of the free tuner viewer so I gotta upgrade.
1994 MX-3 BPT
I was on the BPT with New Zealand ECU since 2004, but after having a few electrical parts starting to fail i figred I would go with MS - microsquirt.
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02-26-2017, 10:28 AM
#2
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I have WUE: 105@138*, 103@154*, and 100@175*
Trust yourself, you made a change, got bad results. Changing it back makes sense.
As a thought, Emilio says more power at 180* than 190*. This tells me that a little more fuel is needed even at 180*, so certainly at 150*.
I'm not where I can see your msq and log. But you may also want to adjust temperature correction of AE, X-TAU, or EAE, whichever you are using.
Trust yourself, you made a change, got bad results. Changing it back makes sense.
As a thought, Emilio says more power at 180* than 190*. This tells me that a little more fuel is needed even at 180*, so certainly at 150*.
I'm not where I can see your msq and log. But you may also want to adjust temperature correction of AE, X-TAU, or EAE, whichever you are using.
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02-26-2017, 02:18 PM
#3
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are you running narrowband?
there's no significant fueling difference throughout that log.
your MAT corrections will cause issues. I'm assuming your fuel fuel is advertly rich and when your AITs heat up, it leans out. I'm guessing youre getting poor mpgs right now?
there's no significant fueling difference throughout that log.
your MAT corrections will cause issues. I'm assuming your fuel fuel is advertly rich and when your AITs heat up, it leans out. I'm guessing youre getting poor mpgs right now?
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02-26-2017, 05:03 PM
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I checked out the inside of a few cylinders as I did have the issue before with the NewZealnd ecu the past year or so. I just used a remote start to get around the sputter period to let it warm up. cyl 2 spark plug thread a little oily and cylinder looks wet (attaching images). My compression gauge release valve is blown so i going to get a replacement.
Spark plugs tips black if that helps but I guess that is more of rich issue?
Thanks
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02-26-2017, 05:26 PM
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were you talking about mat/clt correction which i have all flat like posted on https://www.miataturbo.net/megasquir...n-table-80897/
I know i should have a wideband but theoretically i should be able to get a decent ride with narrow. is the o2 sensor what TunerStudio uses for tuning WUE or does it just take the tables and modifies based on math? My wife might kill me if i spend another $100+ also I would hate to foul up a new wideband or are they not that prone to getting fouled up?
Thanks for you guidance, it is appreciatd.
I know i should have a wideband but theoretically i should be able to get a decent ride with narrow. is the o2 sensor what TunerStudio uses for tuning WUE or does it just take the tables and modifies based on math? My wife might kill me if i spend another $100+ also I would hate to foul up a new wideband or are they not that prone to getting fouled up?
Thanks for you guidance, it is appreciatd.
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02-26-2017, 07:50 PM
#7
anything that tunerstudio does via VE Analyze MUST have a wideband. it compares your AFR target table to what it sees from the wideband.
you're just going to chase your tail trying to tune with the narrowband. unless you don't follow install instructions you won't ruin the wideband.
you're just going to chase your tail trying to tune with the narrowband. unless you don't follow install instructions you won't ruin the wideband.
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02-26-2017, 08:11 PM
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I can ruin a wideband by it not being a tuning issue with my car. i tried to run a compression test (gauge busted) but I found cylinder #2 has water. Please don't blame the few miles I ran with narrowband as the culprit. More likely it is has been like this a while as I had rough starts before.
Last edited by nolig2278; 02-26-2017 at 08:12 PM. Reason: adding pics
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02-26-2017, 10:48 PM
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Is this a crack in the head that can be repaired or am I looking for another head? If I am looking at a total rebuild then I may try head gasket repair for however long that lasts. I drive 30 miles a week with this car. 6 start ups a week.
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02-26-2017, 11:28 PM
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One more horrifying picture :(
If i am reading this right, i warped the **** out of either my head of block or a little of both. is there any miracle of a chance that this would simply be a matter of a stretched pair of head bolts since i used them 2x plus the factory install? This engine did last me over 10 years and many of those were brutal rush hour bumper mixed with 80 mph, 25 mile each way runs at 13 psi in South Florida heat. I even drowned her once in a flood off 95.
If i am reading this right, i warped the **** out of either my head of block or a little of both. is there any miracle of a chance that this would simply be a matter of a stretched pair of head bolts since i used them 2x plus the factory install? This engine did last me over 10 years and many of those were brutal rush hour bumper mixed with 80 mph, 25 mile each way runs at 13 psi in South Florida heat. I even drowned her once in a flood off 95.
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03-02-2017, 10:25 PM
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So I pulled the head, and I think it is warped but I am waiting for feeler guage to know if bad. I could see light under straight edge. I noticed a few chips that I marked in these images. Should I be concerned with them? Also i noticed the pistons are not perfectly centered, is this normal or more bad sign of block/rings/rod/crank warpage? The cylinder walls are too dirty to see if scratched yet, so I will clean this weekend. Head gasket sort of seemed like one layer may have warped, but i mangled that layer when i removed the head. I checked my records and I have been adding little amounts of coolant since i did my gasket replacements in 2010, but never smoked. Rough starts were not there back in 2011 that is something that more recently happened, before MS.
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03-03-2017, 07:24 AM
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I will but right now I need to plan my rebuild so any advice on how much I must tear apart and machine would be really helpful. I am hoping to not have to touch the pistons or replace the entire head but the piston spacing and the chip on head might be an issue?
At the least I am getting:
Wideband
Head Studs
MILS head gasket
thermostat
valve cover gasket
At the least I am getting:
Wideband
Head Studs
MILS head gasket
thermostat
valve cover gasket
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03-06-2017, 11:54 PM
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Yyou over heated and warped everything because you tried to tune with a narrowband, and likely were far too lean causing it to get extremely hot. You are now paying for a rebuild and machining of surfaces because you did not get an essential part that the ECU needs to function properly.
As my sig states
As my sig states
"Cheap usually costs more and rushing things usually takes more time."
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03-07-2017, 04:59 PM
#16
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A narrow band o2 sensor is an oxygen sensor that is only calibrated to know three things. Rich, stoic, and lean. What I mean by this is that it only has a narrow window that it see’s the air fuel mixture through. The sensor can tell the computer when it’s stoic. If it’s not stoic, it can tell the ECU that it’s either Rich, or Lean, but that’s it. It doesn’t really output any particular value other than that. How rich the car is the sensor has NO IDEA about. Same with how lean the car is. All it does know is that it’s not stoic. The ecu with a narrowband o2 sensor, when in closed loop mode, will then lean on the fuel map if it is receiving a rich signal from the o2 sensor till its stoic. The opposite would be true if the sensor was telling the ECU that it was currently running lean, it would richen the fuel map till the o2 sensor was reading stoic.
A wideband o2 sensor is much more sophisticated than a narrowband sensor, and can be relied upon to be used as a tuning tool. Wideband sensors not only are a lot faster acting in the reading, but can tell you the exact a/f ratio that the motor is currently at. So instead of just telling the ECU that the motor is running rich, it will read a voltage that correlates to an actual value, like 11.2. One thing to remember with a wideband sensor is that it has a heating element that needs to be heated up before the sensor will be accurate in its readings. This usually only takes a few seconds, but just remember that for those first few seconds the gauge is not useful. Wideband sensors give the ECU the ability to tune exact A/F value’s to a tenth of a decimal instead of just richening and leaning the mixture till a stoic value is seen.
A wideband o2 sensor is much more sophisticated than a narrowband sensor, and can be relied upon to be used as a tuning tool. Wideband sensors not only are a lot faster acting in the reading, but can tell you the exact a/f ratio that the motor is currently at. So instead of just telling the ECU that the motor is running rich, it will read a voltage that correlates to an actual value, like 11.2. One thing to remember with a wideband sensor is that it has a heating element that needs to be heated up before the sensor will be accurate in its readings. This usually only takes a few seconds, but just remember that for those first few seconds the gauge is not useful. Wideband sensors give the ECU the ability to tune exact A/F value’s to a tenth of a decimal instead of just richening and leaning the mixture till a stoic value is seen.
And with respect to the questions regarding the head, you take it to a machine shop and they measure everything and tell you what it needs.
Or you just guess.
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03-07-2017, 06:59 PM
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I measured everything with .04 mm feeler and nothing is warped 
wahoooooooo. It looks like my years of a slow leak that only recently became a noticeable issue other than filling reservoir was likely because if the dowels being messed up. IT got worse over time because the black material on the MLS head-gasket flaked away over time and allowed fluid to get through. There is also a chance the head bolts were stretched since it was at least their 3 install from factory back in the early 90s or late 80s (I have an imported BPT). Yes, i will get a wideband. It would have been nice to get a dual output wideband to MS and to my narrow autometer gauge (it matches and didnt want to rip pillar apart) but Innovate rep seem to have talked me out of it. I just need the gauge for a very rough lean rich idea since the MS will be handling the real o2 math. That gasket was on for about 28000 miles over 5 years with whatever happened.
My parts list
Studs $25 mahle or $100 arpHead gasket - MLS felpro or might spend the extra for cometic, Valve cover gasket, Injector insulators (2 cracked but tips look fine, should I be worried), Wideband MTX-L, Fuel filter,Timing belt -maybe, thermostat, Exhaust gasket Dowels (where can I find these)
wahoooooooo. It looks like my years of a slow leak that only recently became a noticeable issue other than filling reservoir was likely because if the dowels being messed up. IT got worse over time because the black material on the MLS head-gasket flaked away over time and allowed fluid to get through. There is also a chance the head bolts were stretched since it was at least their 3 install from factory back in the early 90s or late 80s (I have an imported BPT). Yes, i will get a wideband. It would have been nice to get a dual output wideband to MS and to my narrow autometer gauge (it matches and didnt want to rip pillar apart) but Innovate rep seem to have talked me out of it. I just need the gauge for a very rough lean rich idea since the MS will be handling the real o2 math. That gasket was on for about 28000 miles over 5 years with whatever happened.My parts list
Studs $25 mahle or $100 arpHead gasket - MLS felpro or might spend the extra for cometic, Valve cover gasket, Injector insulators (2 cracked but tips look fine, should I be worried), Wideband MTX-L, Fuel filter,Timing belt -maybe, thermostat, Exhaust gasket Dowels (where can I find these)
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