02-16-2013, 02:20 PM
Join Date: Jun 2006
Total Cats: 42
Can raw fuel ruin a Bosch LSU 4.2?
I've taken the LC-1 from my 'old' MK1 MX5 and put it in my new MK2.5.
It's not been used in 12 months, and the last time it was used it was working, however the engine died in the MK1 from a valve spring snapping.
THis meant zero compression on Cyl1 and was driven as such for a mile or so until it was safe to stop.
The engine is now fine lukily replacing the spring was all that was required, but during diagnosis the engine was started multiple times.
Now the LC-1 is in my MK2.5 it just won't give a realistic reading, there are no error codes, and it is 100% wired in properly.
When you calibrate in free air it's fine, reads 20:1+ etc, but as soon as you put it in an exhaust stream the AFR's it's reporting are bonkers 30-40:1
This is from Logworks btw, so there's no weird voltage offset going on.
The only thing I can think it is, is the sensor is borked from being dowsed in unburnt fuel, but can anyone confirm my theory before I stump up money for a new sensor?
Alternatively can it it cleaned/resurrected somehow?
TL;DR - LC-1 sensor gives funny readings after being dowsed in unburnt fuel, wants to know if it's now dead.