non-Renault, BMW diesel Q

[bidderman1969]

working tonight, as usual, only exception being lots of water around, went through a few floods, last one (which i didnt see) was quite fast, then on way back quite slowly as it was deeper than i thought, back to taxi rank, waited about 20 mins, next job ment going up a steep hill, the lights started going dim/normal/dim/normal/dim/normal until i levelled out (had display on charge cycle, and was erratically charging, but no alternator light), the chap paid, got out, went i turned round and was leaving, the amber "check engine!" light came up on dash. Stated idling quite high on its own, Turned car off, had bonnet up to see if it was p155ing oil out everywhere, nope, no major water leaks either. Waited for about 5 minutes, restarted, did it again, turned it off, had another look under bonnet, waited another 5 mins, started it again, light came on again, but went off, decided to go home as didnt want to be stranded just in case, and it never came on again all the way home (11 miles)

so,

a) is there anything to worry about? sensor got wet?

b) should i get the garage to run a diagnostic on it just in case?

c) could it be just some flood water in somewhere? as i couldnt actually see the air intake/air filter on it!

d) what exactly is the "check engine!" light for?

Rover 75, 2002 2.0 TD 215K mileage auto

 

[Chris H]

a) alien invasion, terrorist attacks, disease, recession are all things to worry about.

b) It wouldn't hurt beware of the costs involved though. Also plugging it in doesn't tell you the issue most of the time.

c) could be but it should dry out pretty quick if its sensors etc. If its airbox chances are you'll have to remove it and drain it and new air filter.

d) the check engine light is the MIL. It illuminates after a fault is present for a certain amount of time. basically if a sensor or something is giving an erroneous reading then the ecu through graceful degradation try and recover it but if it won't then the MIL will flag up. When its on ther ecu operates under LOS (limited operation strategy) idiots that say limp home mode need a finger removing.

When in LOS the ecus only concern is maintaining emission limits. Thats all any engine management is trying to do btw. That will explain your higher idle etc as its trying to prevent any damage to the particulate filter (yours should have one).

Anyway check the air filter housing for water, hopefully there won't be any in it and any other water will have been evaporated off with the engien heat.

 

[bidderman1969]

cheers matey! mucho appreciato

last thing i want is the engine to go bang, lol, its a fine reliable lump there, which is what i need, lol

 

[93oem+]

dependant on engine i have encoutered this with my uncles z3 2.8i although this is a petrol engine i believe that the intake is low in most bmw's so quite prone to water ingress. judging by sympoms id agree with what chris has said!
hope you sort the car without to much grievence!

 

[bidderman1969]

Seems to be ok now, fingers crossed!

 

[Chris H]

it'll have dried out

 

[bidderman1969]

Yeah Christ for that! Can't say what was going through my mind, but it involved ££££££