About to fiddle with the MAP via TuneECU on my 2000 885i

[haroldo_psf]

So, I have the lumpy idling which causes occasional stalls, and the surging that is typical of a faulty TPS. I have replaced the ISCV and done a 12 Mintutes tune. The bike runs great for a couple of days, and then the symtoms come back. It is not as bad as before, but I wonder why the degradation happens.

Anyway, I ordered a TPS from a Triumph dealer in California (Mountain View), but there is NONE in the US, and they say it can take months for mine to arrive from the UK.

Does any of you good souls have a way to get one, or have a spare one? I'll pay double of what cost, plus shipping, of course.

In the mean time, I'm gonna mess with TuneECU. the cable is on the mail, and as soon as it arrives, I will mess with these parameters:

1) ISCV idle position
2) Idle fuel trim
3) Target A/F ratio (will change it from 14.7 to 13)
4) Off idle and low rpms fuel trim or ratio, can't remember (will make it richer)

The way the bike runs, if I had to guess, I'd say it is lean at low rpms and at idle. This, in my opinion could be due to the faulty TPS, as it might not read "Closed throttle" properly (or whatever voltage that is), and the ECU doesn't apply the proper mixture. Could this be the case?

How can I tell is the crappy idling is due to a lean or rich condition?

Last evening I took it for a ride, and when the idling became crappy (the bike's "mood" goes up and down...), I tried to take off from a stop light, and the engine didn't follow...There was something that sounded like low missed combustions, like "pop pop pop", but it never became a "Vrooooom!"... Sorry, my limited mechanical skills prevent me from explaining it better...

It is very sluggish off idle and at take off. I read that this could be due to a lean condition, so I'm going to mess with the map. What could go wrong?

Can any of you with a service manual tell me where is the OBD2 connection on the bike? (the connector for the TuneECU cable)

[walker]

the connector for the ECU is right there beside the ECU! It's underneath the passenger seat - it usually sits just next to the crossmember of the frame where the front seat attaches.

Yeah - get the cheap cable, get the tuneECU and reset the TPS FIRST before doing any of that other stuff. There is an option to reset it so that it knows the position at rest. That may fix you right up.

[haroldo_psf]

stupid question...Does the ECU get powered via the OBD II connection?  Or is there a separate power connector that connects it to the battery? I was just wondering how it gets power once its connected to a laptop.

Mu OBD II to USB cable is on its way from China...But I just remembered I have an OBD II to serial (RS232) that I used on my Subaru. I will try to connect a FTDI RS232 to USB converter to it, and see if it works tonight.

[walker]

naw - the OBD connection is just a communications port. Like on a computer, the power supply powers it, but you still have serial / USB ports.

the ECU is hooked into the wiring harness and has power / ground wires as part of that harness.

you're good.

[Bixxer Bob]

H, before you go wading in, do the basics first.  First check for air leaks in the IACV hoses.  Then new air filter and plugs, shim check, then throttle body balance (shims first or the balance is a waste of time).  Then when you connect TuneECU test the IACV to make sure the IACV is working right.  Bear in mind also that one or two folks have cured their low rev issues by changing the throttle body gasket - they are a known problem and prone to leak.  

Then before you go messing with the maps - assuming you still have a problem - try adjusting your long term trim up 0.5 %.

[haroldo_psf]

H, before you go wading in, do the basics first.  First check for air leaks in the IACV hoses.  Then new air filter and plugs, shim check, then throttle body balance (shims first or the balance is a waste of time).  Then when you connect TuneECU test the IACV to make sure the IACV is working right.  Bear in mind also that one or two folks have cured their low rev issues by changing the throttle body gasket - they are a known problem and prone to leak.  

Then before you go messing with the maps - assuming you still have a problem - try adjusting your long term trim up 0.5 %.

Thanks, that's good advice. The valves were checked 8 thousand miles ago by the dealer, and the TB were sync'ed then too. The thing is, I don't trust dealers. There is a reason why they're also called "stealers". I looked at the service history, and they say that all valve clearances were in spec. For some reason I doubt that.

But anyhow, valves, TB, TB gasket were done 8000 miles ago. I just installed a new fuel filter and air filter, and also a new ISCV.

The only thing that has not been done is replace the TPS and the ISCV hoses to the TBs. The TB gasket is also on order with the TBS sensor.

 Is there a good chance that the TPS is the same for my 2000 885i and for the subsequent Girlies (2001 to 2004 955i)?

I wonder if I could find the TPS for another model faster....

[Bixxer Bob]

TB balance 8000 miles ago is a long time.  Shims too if they were in doubt.  It's not a hard job to lift the cover and check, just take your time.

Certainly easier than doing my Blackbird.....