Author Topic: Alternator replaced, now have issues with idle  (Read 8186 times)

Diamshill

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Alternator replaced, now have issues with idle
« on: March 19, 2024, 09:47:03 PM »
Hi, this is my first post so I'll start with a hello to everyone  :D

I have an '09 R1200GS, K25 0303, standard edition bike with 64k on the clocks; cast wheels and rather tatty. About two months ago the bike suddenly stopped and refused to start giving an awful squeaking when trying to turn over. It turned out the alternator had completely seized; the casing was cracked, it was rusty and furred up, the stator showed signs of uneven wear. I sourced a new alternator from France (cheaper than the UK) and went about fitting it. I found numerous posts on how to do this along with the Haynes manual, so out with the old and in with the new.

Parts replaced:
1. alternator, incl. belt, with a shiny new one, same model.
2. Upper throttle cable had a small kink so has also been changed. Routing has been checked and appears correct; as are the lower two.
3. FPC replaced
4. Service - oil, oil & air filters, spark plugs

Everything was fine until the alternator seized, now I have new issues:
5. Initially high, now irregular & low idle.
5a. Removed & cleaned TPS; tested with multi-meter. Appears ok. Reset actuators with GS-911 too
6. Battery appears to have drained despite being new. Cables & connections have been checked and appear correct.

The idle is now quite irregular, and ends up stalling after a while; it recently started with around 2k rpm which then gradually decreased as the bike warmed up until it stalled. Failed to start again without opening the throttle a little.
It seems as though the system can't stabilise itself after the parts were changed or I appear to have missed something after completing the jobs.

Do I need to carry out an adaptations reset with the GS911? On that note, I do have a replacement tps on the way though I'm not sure if this is required.
Also, I've not yet carried out a throttle body synchronisation as I can't get a constant idle. Nor have the O2 sensors been checked or the valve clearances checked.

I am aware of various posts on individual points mentioned but I can't seem to pinpoint any issues/solutions to satisfy the problems.

Many thanks  ;D
« Last Edit: March 19, 2024, 09:59:49 PM by Diamshill »

botus

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Re: Alternator replaced, now have issues with idle
« Reply #1 on: March 19, 2024, 11:49:52 PM »

The idle is now quite irregular, and ends up stalling after a while; it recently started with around 2k rpm which then gradually decreased as the bike warmed up until it stalled. Failed to start again without opening the throttle a little.
It seems as though the system can't stabilise itself after the parts were changed or I appear to have missed something after completing the jobs.

Do I need to carry out an adaptations reset with the GS911? On that note, I do have a replacement tps on the way though I'm not sure if this is required.
Also, I've not yet carried out a throttle body synchronisation as I can't get a constant idle. Nor have the O2 sensors been checked or the valve clearances checked.


Many thanks  ;D

its won't be adaptions.....   although real time values of the Engine and check long and short term trims to see how out of whack they look if you want

people like electrics and diagnostics to do the basics but they shouldn't

can't believe but seems MANY owners manage to get the throttle cable to sit stupid at the throttle body ends (after fiddling with the bike) and they run horrible - check both full open and close together - u see / feel it round the back (inside face) of each throttle body

next the bikes fuel pumps give up and they get weird on low fuel pressure - check, might be an outstanding free recall for a new pump - many this age got one (due to cracks and fuel leaks - or check history if it had one in less than 25k miles ought to be OK - buy pikey fakes off ebay for £40 they are better than OEM)

if that's not helped

1) I'd do the valve clearances - easy on either the older screw and lock nut ones OR the twin cam with spherical shims
2) then to ensure an easy life do a compression test if they are healthy and about equal
3) try carb balance using vac gauges with the throttle cable holding revs around 3k rpm on a hot engine - when correct turn off, snap throttle open and closed a few times re start and recheck

if that's not having it, coil stick failures is NORMAL but should be struggling to pull hard after 4k rather than idle issue
« Last Edit: March 19, 2024, 11:52:05 PM by botus »

Diamshill

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Re: Alternator replaced, now have issues with idle
« Reply #2 on: March 20, 2024, 03:52:17 PM »
Thank you for the quick response  8) I've not had the chance to do a valve clearance check yet as the protection bars have three stuck bolts which prevent their removal; bit reluctant to cut them off at the moment.
I ran the engine earlier today and it seemed to maintain idle although a little higher than normal at between 16 & 18k. I plugged the 911 in and ran the live data; the data received are as follows (first value=engine off; second value=engine running at warmed temperature):

Injection time   0.0   2.9 ms
Lambda control factor 1   1.0   .08
Lambda control factor 2   1.0   0.8
Speed   0.0 mph   0.0 mph
Engine RPM   0 rpm   1710 rpm
Air temperature   23.2 °C   35.2 °C
Engine temperature   42.8 °C   93.0 °C
Temperature (cylinder head 1)   45.0 °C   95.2 °C
Temperature (cylinder head 2)   45.0 °C   95.2 °C
Ignition angle   96.0 °KW   20.2 °KW
Throttle valve position   9.02 %   9.41 %
Engine load   45.58 %   21.27 %
Battery voltage   12.60 V   14.20 V
Knock sensor 1   48.83 V   20.12 V
Knock sensor 2   48.83 V   16.82 V
Ignition dwell time   2.3 ms   1.9 ms
Gear position   N   N
Idle actuator position 1   204.0   80.0
Idle actuator position 2   204.0   80.0
Ambient air pressure   1003 mBar   1003 mBar
Lambda sensor voltage 1   449.2 mV   918.0 mV
Lambda sensor voltage 2   449.2 mV   566.4 mV
Side-stand switch 1   Extended   Extended
Side-stand switch 2   Extended   Extended
Side-stand switch calculated   Extended   Extended
Clutch switch   Not Actuated   Not Actuated
Kill switch   RUN   RUN
Oil switch   OK   NOT OK
Start switch   Not Actuated   Not Actuated
Tank venting valve   OFF   OFF
Engine over-temperature light   OFF   OFF
Actuation of starter relay   OFF   OFF
Lambda sensor heating 1   OFF   ON
Lambda sensor heating 2   OFF   ON
Fuel pump   OFF   ON
Engine safety cut-out (of BMSK)   OFF   OFF
Starter function (of BMSK)   ON   ON
Starter safety cut-out (of BMSK)   OFF   OFF
Malfunction Indicator Light (MIL)   OFF   OFF
Additive Trim bank 1   -1.36 %   -1.36 %
Additive Trim bank 2   -2.44 %   -2.44 %
Multiplicative Trim bank 1   0.9   0.9
Multiplicative Trim bank 2   0.9   0.9

My lower coil packs are quite rusty with deterioration around the middle and some parts have flaked off exposing the inner housing on one of them; measured values still appear ok though I'm considering replacing them anyway.
All throttle cables are free and seated correctly.
Fuel pump is ok and operating correctly; no cracks or obvious damages.