nightmare tuning experience so far...need help
Long story so, the cliff notes:
*car ran fine stock, had a cel light with codes p0430/0420(catalytic converters - were replaced with 200 cell)
*loaded the new map and upon start-up with the door open, heard a very loud/brief rasp/rattle that I assumed was the exhaust - cel light remained on
*took the car out for about 5 miles and seem to run fine with a noticeable change in performance (mostly for the better), realizing that it'd take some time to adapt before I could really judge
*got home and noticed while parked/idle, a fairly consistent top-end knocking (almost sounded like a stuck lifter with a bit of an echo?). turned the car off, restarted with things sounding ok for about 3-4 seconds then the 'knock' returns
*reloaded the oem map, started the car with the same thing - 3-4 seconds ok with 'knock' returning
*hooked up BAFX/torque(new to me), confirmed above cel codes and cleared them
*restarted on oem map with knock instant and growing in volume within seconds - turned car off immediately
*waited a bit - started again, with car just like before clearing the codes - 3-4 seconds ok then knock
*let some time pass, and started the car again with instant loud/bad chugs/rasp - turned it off figuring I just broke it(I had just done the HBs, lifters, etc a few weeks earlier)
*with it blocking my daily driver and in a F-it mode now, started it again - got that same loud/brief rasp/rattle when I 1st started it with the previous 'new map', and then... it ran/sounded perfect?! With it being late and happy to end it there, got it parked in a place that I could pull the covers if needed, which I really would like to avoid.
note: several e-mails exchanged with the company during this time.
I'm 'educated' enough to change out HBs, lifters, etc but far from some master mechanic and am aware that the new tune along with some spirited driving could've push some existing issue over the edge, but this drastic and random of an issue leads me to be believe its not mechanical. I asked the company if it was possible (not probable) that something could be corrupted with the ecu with the answer (finally) being no. I also asked they had an oem map(need not be original) they could send me just to try - LSS, guess if you believe there's no way that there's something corrupted, why bother?
Anyway, does anyone have some mechanical explanation for what I'm experiencing?
Or, does anyone with more ecu/tune experience than me(limited to a Cobb/Subaru before this) disagree with it being impossible that the ecu/oem map(that was uploaded from the car) could become corrupted during the process, otherwise it wouldn't load.
Any info/help appreciated - either way, it's been a bit therapeutic to type this out
you say you did lifters and headbolts not long ago what about the cam adjusters? Could be something there perhaps although if you are getting catalyst codes I would try and figure that out first, maybe they could send a tune with catalysts monitoring off and try that see if the sound goes away?
Sound like something mechanical is going on
1) When you re-loaded the OEM map into your ECU, the problem not only persisted, but actually got worse over repeated restarts of the car.
2) You describe the same knocking sound after the tune was installed and then still present after restoring the OEM map.
Both items sound like a mechanical failure. In any event, you should STOP trying to restart the vehicle as the problem appears to be getting progressively worse from your description. If it was a software problem, once you reloaded the OEM map, you over-wrote the tuned code. I've heard of very rare instances of ECU's sometime being damaged when they are sent in for a bench tune, but you said you did yours via OBD port. So as long as both the tune and restoration processes completed without error, the ECU should be OK. Could the tune have caused the failure of a marginal mechanical part by just stressing it just a little bit more than normal? Sure, but that's the chance one takes. If you want to put your mind to rest, ask the tuner to send you another copy of your OEM file for your device. However, don't be surprised if repeating the restoration process doesn't fix the problem. You appear to have a mechanical failure at this point.
you say you did lifters and headbolts not long ago what about the cam adjusters? Could be something there perhaps although if you are getting catalyst codes I would try and figure that out first, maybe they could send a tune with catalysts monitoring off and try that see if the sound goes away?
Replaced one adjuster that had a chronic start-up noise (consistent) and flipped pins on the others - again, no expert but can't imagine them causing the car to sound like death on one start-up and then adjust to run perfect?
1) When you re-loaded the OEM map into your ECU, the problem not only persisted, but actually got worse over repeated restarts of the car.
2) You describe the same knocking sound after the tune was installed and then still present after restoring the OEM map.
Both items sound like a mechanical failure. In any event, you should STOP trying to restart the vehicle as the problem appears to be getting progressively worse from your description. If it was a software problem, once you reloaded the OEM map, you over-wrote the tuned code. I've heard of very rare instances of ECU's sometime being damaged when they are sent in for a bench tune, but you said you did yours via OBD port. So as long as both the tune and restoration processes completed without error, the ECU should be OK. Could the tune have caused the failure of a marginal mechanical part by just stressing it just a little bit more than normal? Sure, but that's the chance one takes. If you want to put your mind to rest, ask the tuner to send you another copy of your OEM file for your device. However, don't be surprised if repeating the restoration process doesn't fix the problem. You appear to have a mechanical failure at this point.
No doubt could be the car and on me (and told them that up front).
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Pull the valve cover and turn the engine over and see if the cams turn in time.
Last edited by layzie12g; Dec 28, 2018 at 11:53 PM.
Regarding info on cam adjusters, I highly recommend checking out Tasos M156 youtube videos. When doing my HBs, that's where I got info on a CA pin flip and he was nice enough to respond to a post I made on some cam 'slap' I was getting while turning the crank (was a completely worn CA pin cavity requiring replacement). The drastic inconsistency I have has me thinking it's something else, but replacing a CA is a whole lot easier/cheaper than a cam so will try to rule it out 1st.










