Occasional Buck
#1
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Hey guys, got an issue that bugs me a bit, just curious if anyone has any input
specs
93 NA with a SNC 1.6l
MS1 3.0
stock coils
mitsu 16g
dsm 340cc
blah blah
problem im getting is, occasionally, more random, nothing specific causes it, it can do it under load, or not
i get a buck. like a cylinder cuts out, then comes back, like i said it will just randomly do it when driving, very rarely it will do it in boost.
other question is, which im leaning towards either the turbo seals or valve stem seals
if i completely let off the throttle, engine brake, then start giving it gas again, it smokes, but thats the only time.
now, its not the PCV or breather, as i can unhook both, and it still does it at the same situation.
im replacing the turbo tomorrow, so that will eliminate the possibility of that, assuming it still smokes
specs
93 NA with a SNC 1.6l
MS1 3.0
stock coils
mitsu 16g
dsm 340cc
blah blah
problem im getting is, occasionally, more random, nothing specific causes it, it can do it under load, or not
i get a buck. like a cylinder cuts out, then comes back, like i said it will just randomly do it when driving, very rarely it will do it in boost.
other question is, which im leaning towards either the turbo seals or valve stem seals
if i completely let off the throttle, engine brake, then start giving it gas again, it smokes, but thats the only time.
now, its not the PCV or breather, as i can unhook both, and it still does it at the same situation.
im replacing the turbo tomorrow, so that will eliminate the possibility of that, assuming it still smokes
#6
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I don't know if this applies to MS1 but...
I had the same issues on MS2. It was getting sync loss on the CAS signal. Just log when it happens (easier said than done). If it's a sync issue, you will see "Sync Loss Count" count go up, and "Sync Loss Reason" will go to 38 or 39.
Building an opto isolator circuit fixed it for me.
I had the same issues on MS2. It was getting sync loss on the CAS signal. Just log when it happens (easier said than done). If it's a sync issue, you will see "Sync Loss Count" count go up, and "Sync Loss Reason" will go to 38 or 39.
Building an opto isolator circuit fixed it for me.
#7
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
I don't know if this applies to MS1 but...
I had the same issues on MS2. It was getting sync loss on the CAS signal. Just log when it happens (easier said than done). If it's a sync issue, you will see "Sync Loss Count" count go up, and "Sync Loss Reason" will go to 38 or 39.
Building an opto isolator circuit fixed it for me.
I had the same issues on MS2. It was getting sync loss on the CAS signal. Just log when it happens (easier said than done). If it's a sync issue, you will see "Sync Loss Count" count go up, and "Sync Loss Reason" will go to 38 or 39.
Building an opto isolator circuit fixed it for me.
#8
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i had a similar issue but mine is during cruise. At the event my afr's would drop into the 12's then pop up to 15:1-16:1 and be fine again. it seemed to me like it was getting a false acceleration signal cause my injector PW would jump up just before each event. so i opened acceleration wizard on tunerstudioMS to check my settings and everything looked good so i drove with it open to see if the green ball was jumping around but it stopped doing it. at first i was mad cause it wouldnt fail while i was watching so just saved my settings and closed the window. that was 2 weeks ago and it has yet to act up yet and i drive the car daily. not sure what fixed it but it stopped.
#17
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car is running better now, still running e85. running 10psi on the 57/73mm, 12 makes clutch slip.
found myself running short of fuel saturday night, out messing around, after 4000rpm my afrs started dropping to 13.2
pulled the 305cc's today, threw in some low imp 660cc's, after rewiring the injector harness, i retuned the fuel, however, im having an issue at idle, its popping and idle searching
any ideas?
found myself running short of fuel saturday night, out messing around, after 4000rpm my afrs started dropping to 13.2
pulled the 305cc's today, threw in some low imp 660cc's, after rewiring the injector harness, i retuned the fuel, however, im having an issue at idle, its popping and idle searching
any ideas?
#19
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so with gas or e85
340cc or 660cc
more advance or retarded timing
too rich to lean
i still get the buck, i completely redid my settings in TS, even disabled accel/decel, still have the buck. its almost like im loosing power when it bucks, since the tach and oil pressure gauge drops as seen in the video.
wet or dry out doesnt make a difference, however im wondering if i have a failing coil, or if by the off chance i have a spark plug partly fouled. although even if it was a miss from a plug, the tach wouldnt drop 800rpm then bounce back
the IAT is hooked up now as well, and still no change
340cc or 660cc
more advance or retarded timing
too rich to lean
i still get the buck, i completely redid my settings in TS, even disabled accel/decel, still have the buck. its almost like im loosing power when it bucks, since the tach and oil pressure gauge drops as seen in the video.
wet or dry out doesnt make a difference, however im wondering if i have a failing coil, or if by the off chance i have a spark plug partly fouled. although even if it was a miss from a plug, the tach wouldnt drop 800rpm then bounce back
the IAT is hooked up now as well, and still no change
#20
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so it turns out in my case, i had killed the plug wires in less than 7k miles (ngk's) and fouled 1 plug. replaced those, double checked base timing with light, was 3d advance, changed that, and its running alot smoother now, still a random pop every now and then, but no where near as bad as before