MAF?

[moranor@axis]

ive been having an intermittent misfire (about one every few months) every time the same codes come up:

code1:
202 Fuel trim bank 1 control limit (OBDIIO170;EUIIIO170)

code2:
203 Fuel trim bank 2 control limit (OBDIIO173;EUIIIO173)

code3:
242 missfire, cylinder 5 (OBDIIO305;EUIIIO305)

code4:
243 missfire, cylinder 6 (OBDIIO306;EUIIIO306)

code5:
241 missfire, cylinder 4 (OBDIIO304;EUIIIO304)

code6:
8 Signal, air-mass flow sensor (OBDIIO101;EUIIIO101)

if i keep driving it stops after a while... also i have noticed if i stop turn the car off then start it again it seems to go away...

i changed part 3 & 5 on this pic because they were cracked and cleaned the maf... but it still happens...

i suspect it might be the maf going because every time i work near or move the maf it seems to happen on the next start up...

am i on the right track or am i missing something?

 

[MikeR]

:thinking: maybe this was the fault :dunno:

i used carb cleaner the other day because i could not find maf cleaner... seems fine so far :dunno: maybe i should try some on some plastic bits and see what it eats...

i love the warning label on the can...
Danger: harmful or fatal if swallowed

I hope not....good luck fault finding. try cleaning it with Electrical cleaner rather.

 

[P1000]

Change the MAF. Once they start to go, it is downhill from there, no cleaning can save them. Do some research on the net, and get the generic Bosch part number for the cartridge, and replace only that. (basically on the the MAF+electronics, not the entire housing, it will be cheaper)

 

[zaleonardz]

Argh... its highly frustrating.

I wish you were able to rent components one at a time to try and find errors.

I hate the fit parts and see which one fixes the error game, but sometimes you have no choice......

 

[P1000]

It is usually easy to diagnose MAF problems with the right ODB software and a short trip... (monitor and graph the MAF reading) (I will start reverse-engineering INPA tomorrow so that I can write something that can do just that)

 

[moranor@axis]

if i change the maf i want to fit a bigger one any suggestions?

 

[P1000]

if i change the maf i want to fit a bigger one any suggestions?

Umn, why? I don't think you would get away with it, since the scaling would probably differ, so you would need to remap before you will be able to drive the car. Rather hold out for when you know exactly what you want to do with engine management when you turbo the car...

 

[Philip Foglar]

Argh... its highly frustrating.

I wish you were able to rent components one at a time to try and find errors.

I hate the fit parts and see which one fixes the error game, but sometimes you have no choice......

Yep, becomes an expensive process of elimination! :mmm:

 

[moranor@axis]

if i change the maf i want to fit a bigger one any suggestions?

Umn, why? I don't think you would get away with it, since the scaling would probably differ, so you would need to remap before you will be able to drive the car. Rather hold out for when you know exactly what you want to do with engine management when you turbo the car...

the problem is no matter which way i go i will need better airflow and the maf is a major restriction so if i can change it now i would rather go bigger now than fit the same size now and have to change it later anyway...

 

[moranor@axis]

just did the tap test and nothing happened im not very keen to buy a maf only to find out its not the problem...

i have not yet taken the intake manifold off to check for leaks, but to me it seems like a long shot because its so intermittent and when i turn the car on and off again it goes away :thinking: to me it seems like an electric type problem...

when i dynoed my car it was a bit down on torque the tech said it could be dirty injectors... is it worth trying to clean them? bear in mind that it rains here alot so there should be plenty of steam to keep them clean :dunno:

 

[Venom]

http://www.schmiedmann.com/13627567451/product-type/New/search-by-productnumber.aspx

or

http://www.bmwpartsweb.com/BMW-Parts/Air-Mass-Sensor-E39-01-03-530i__13627567451-SIEMENS-E39530.aspx

Don't get ripped off!

 

[moranor@axis]

thanks

im not sure its the maf yet the tap test did not bring up anything

i have also noticed that on the highway when i plant my foot the car seems to hiccup then go... its very slight... this is also a maf type symptom but i guess it could also be caused by something else

 

[P1000]

Try to disconnect the MAF and see if it runs better then.

 

[moranor@axis]

the thing is its running smooth since i cleaned the maf... but i still got a misfire after cleaning ill try unplug it and see... wont unplugging it put the engine light on? or send it into limp mode?

 

[P1000]

the thing is its running smooth since i cleaned the maf... but i still got a misfire after cleaning ill try unplug it and see... wont unplugging it put the engine light on? or send it into limp mode?

It shouldn't. Do you have INPA? Oh, and when a MAF starts showing problems, 9/10 times cleaning it will not completely/permanently fix it...

 

[moranor@axis]

dont have INPA waiting on rick540 so it may end in me limping to a workshop to get it reset

 

[moranor@axis]

think its time to change the maf yesterday the econometer was going metal and the car felt a bit sluggish... ill clean it again and start getting prices on mafs...

where should i start 'diesel electric'?

 

[P1000]

Also call a Bosch service centre or bosch directly and ask for the nearest distributor (might be a Midas or the likes)

 

[moranor@axis]

i know of two bosch dealers in pmb... what do you think of Meyle mafs... they have them in stock at incomex...

what sort of price do you think it should be? im thinking R1500-R1800

 

[P1000]

Price seems right after discount. I would try to go for an oem MAF, aside from the abysmal service I have received from Imcomex...