Is300 E-Shift/auto-Box Problem

[5nowy]

Hey folks, the internet is proving a difficult hunting ground for information so I thought I would pop a post in here.

The e-shift and auto gearbox on my 2002 IS300 is playing up - the usually very responsive box becomes less so, and when shifting into e-shift I get the M on the dashboard flashing indicating a problem. This is not a permanent issue, sometimes it seems to come back for no discernable reason, and likewise it will go off for no discernable reason.

Has anyone encountered a similar issue? I am keen to explore any "You might want to check X" avenues before paying a Lexus dealer to investigate.

Over to you, any and all advice most welcome.

Cheers

[Rory]

Last time I read of a gear issue on is300 it was leaking gearbox oil, I myself have no idea tho, whether it suffered the same symptoms...

[5nowy]

Hi Rory, thanks for the response. There is no leakage at all, checked thoroughly.

I have had a look around on the web (amazing how changing your search can yield better results) and the prevailing logic is that two options to look at before booking it in with Lexus are to reset the ECU and clean the MAF.

So - I am no mechanic, not even close. I can't find any instructions to reset the ECU, so first off can anyone supply such? Secondly how tricky is it to remove and clean the MAF? I understand that it has quite a fine needle that is easily damaged, would I be better getting a mechanic to take a look or is it a reasonably easy job?

Anyone wanting to point at the non grease-monkey and laugh can do so, but only once they post some help ;)

[steve2006]

Normally pulling out the EFI fuse for 5 minutes will reset the ECU, the fuse is normally located in the engine bay fusebox and the cover is marked with the fuse types and what each one does.

Alternatively pull off the negative Battery lead,wait 5 minures and reconnect BUT make sure you have any radio codes before doing this as it may ask for one on reconnection, if you are not sure leave it alone.

Cleaning the MAF sensor can be done by spraying the wire with a non residue contact cleaner and allowing it to dry naturally so no brushing which can damage the wire.

It may also be worth having the diagnostic codes read this doesn't have to be a Lexus dealer any competent garage should be able to do this for a few pounds, if you get any stored codes post them up.

Obviously you have checked the transmission fluid level and made sure it is a cherry red colour on the dipstick not a dirty brown.

Another possible cause is defective shift solenoids in the transmission but go through the other checks 1st.

[5nowy]

Thanks Steve

I reset the ECU but that hasn't fixed the issue, so will look to clean the MAF sensor next, and will also look to get the diagnostic codes checked if that doesn't resolve it.

Obviously you have checked the transmission fluid level and made sure it is a cherry red colour on the dipstick not a dirty brown.

Oh how that 'obviously' stung :D I was so tempted to come back and say "Of course, that was my first check" but that would have been something of a lie! Anyhow, I checked that too and the transmission dipsitck was fine, no nasty brown fluid.

Fingers crossed it is the MAF anyhow, watch this space.