BMW engine failure. What caused this?
Discussion
You need to anaylze the remap parameters, the injector was probably already leaking, remap increased fuel, fuel left , detonation.
Most likely injector was working over safety parameters, ecu wouldn't process it. I don't think you need an expert, remaps on older cars should be used with caution, an injector test at the least.
Most likely injector was working over safety parameters, ecu wouldn't process it. I don't think you need an expert, remaps on older cars should be used with caution, an injector test at the least.
MJ85 said:
After, tried to start, just turned over. Garage replaced injector 6 which had a missing “end”, car ran, but badly.
Engine stripped down, pics as shown.
Just a thought but could the missing injector parts have visited the other cylinders? I've seen that happen on a RV8 where debris has travelled about via the inlet manifold.Engine stripped down, pics as shown.
MJ85 said:
Not likely to be misfueled.
Was running very well until the point of failure.
Had been hard driving just before failure, but not actually the second it went wrong.
Engine went “bang”, loads of smoke out the back, engine ran on its own with no input from me, past the redline, then cut out.
Map hadn’t been on there long, generic. Recent oil change, air filter change, otherwise good.
Thank you.
That adds complication. The engine running on its own oil could be the cause if the piston erosion, which would have been totally uncontrolled combustion....ie also detonation.Was running very well until the point of failure.
Had been hard driving just before failure, but not actually the second it went wrong.
Engine went “bang”, loads of smoke out the back, engine ran on its own with no input from me, past the redline, then cut out.
Map hadn’t been on there long, generic. Recent oil change, air filter change, otherwise good.
Thank you.
Or it could have been a symptom/effect from something else.
Check entire breather system is good, turbo is working correctly etc and that there are no other potential sources of oil..ie fuel into the engine that could cause the running away.
And have the injectors tested, or what is left of them.
When you say not long, like hours, days, weeks, months ? 10 miles, 1000 miles ?
Not a simple fix....IMO replace or repair the entire engine checking the above and either have it mapped by a reputable place or have it put back to standard.
With the drip feed of information we are getting here....
At only 500 miles until it's blown up, that surely cannot bode well for the quality of the remap. It may or may not be a direct cause...but it seems highly likely it is one causing factor here. Whether the only one or not, hard to say.
At only 500 miles until it's blown up, that surely cannot bode well for the quality of the remap. It may or may not be a direct cause...but it seems highly likely it is one causing factor here. Whether the only one or not, hard to say.
MJ85 said:
Not likely to be misfueled.
Was running very well until the point of failure.
Had been hard driving just before failure, but not actually the second it went wrong.
Engine went “bang”, loads of smoke out the back, engine ran on its own with no input from me, past the redline, then cut out.
Map hadn’t been on there long, generic. Recent oil change, air filter change, otherwise good.
Thank you.
"Engine ran on its own" is the key bit. The only source of fuel when you've lifted off the throttle pedal is the engine's own oil. You need to take the pistons out but I suspect you'll find the lands have collapsed under the detonation from excessive cylinder pressures after the remap and the rings have broken causing sump oil to be dragged into the combustion chambers or pumped into the breather system by piston blowby and hence into the inlet manifold. Is the inlet manifold oily inside?Was running very well until the point of failure.
Had been hard driving just before failure, but not actually the second it went wrong.
Engine went “bang”, loads of smoke out the back, engine ran on its own with no input from me, past the redline, then cut out.
Map hadn’t been on there long, generic. Recent oil change, air filter change, otherwise good.
Thank you.
Remap = too high cylinder pressures and temperatures.
The edges of the piston bowl are pretty highly thermally loaded due to their geometry so it's not surprising that when you go past a certain point erosion becomes a significant problem.
Of course, the BMW engineers have no clue what they're doing and you're better off relying on some backyard garage for your ECU calibration data...
The edges of the piston bowl are pretty highly thermally loaded due to their geometry so it's not surprising that when you go past a certain point erosion becomes a significant problem.
Of course, the BMW engineers have no clue what they're doing and you're better off relying on some backyard garage for your ECU calibration data...
AER said:
PS: It's a diesel engine! Why are we all talking about pre-ignition and detonation...? Those phenomena don't exists on diesels.
Running on it's own oil isn't pre-ignition before you go there.
So you're saying a poor map, or running on it's own oil is perfectly controlled and timed combustion ?Running on it's own oil isn't pre-ignition before you go there.
Uncontrolled combustion etc is pretty much detonation/pre-ignition to me.
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