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Hunting idle speed?


indy

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Hi All,

 

Well, after reading the CCP thread...

 

http://bmwsporttouring.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=760243#Post760243

 

...I just had to futz with mine.

 

I was changing out the stick coils and decided to try the pink CCP again. I was using a jumper for the yellow CCP along a techlusion R259. Bike ran great except for some high end >4500 rpm vib's which I blamed on bad stick coils. (The vib's are now gone).

 

Problem now is the idle is "hunting". After I swapped out the jumper for the pink CCP, and disabled the Techlusion. But then the idle was way off. I tried as best I could to adjust the BBS screws. They're within 1/4 of each other. The idle runs smooth at ~1100 for about 30-40 sec's, then stumbles down to <1000 and the bike wants to stall. With the techlusion enabled it's much much smoother, but still hunts from around 1100 to 1500 rpm.

 

Any help is much appreciated. I suspecting a vacuum leak. I checked all I could see, throttle bodies are fine. Hoses look fine as well. I did a Throttle position reset when I installed the pink ccp. But no luck.

 

The bike runs much better than before but the hunting idle is new.

 

TIA

 

Indy- going back to the yellow jumper is a option

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Afternoon indy

 

Vacuum leaks usually just raise the idle speed on the BMW 1150 boxers so probably not that.

 

Try running it with the o2 sensor disconnected (if that improves the idle quality then we can work from there.

 

If no improvement with o2 disconnected then verify that TPS voltage is under .4 volts at closed throttle (no choke on)

 

Also verify that you don't have the o2 sensor pig tail running anywhere near the R/H lower spark plug wire.

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Thanks AndyS and dirtrider,

 

Yeah, I tweaked the BBS screws. It was idling so bad I turned them all the way in, then backed them out 2 1/2 turns. From there I adjusted them to get the best idle I could. Both are 1/4 from each other at ~2 3/4 turns out from the stops.

 

I'll check the TPS voltage (gotta RTFM first)

 

It may be a plug wire close to the O2 sensor wires. It'll be a couple days before I can pull the tupperware off again. But I'll get back to you asap.

 

Will it hurt to leave the O2 sensor unplugged and run it without, I'm guessing it's only used for mapping?.

 

The only reason I futzed with it was to see if I could gain a bit

of fuel mileage. Not a top priority but , just wanted to see. (I get upper 30's at 85 mph hiway commutes)

 

Thanks again

 

Indy - 02 1150RT with 93K miles and keeping it!

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greiffster

The only reason I futzed with it was to see if I could gain a bit

of fuel mileage. Not a top priority but , just wanted to see. (I get upper 30's at 85 mph hiway commutes)

 

I've seen a lot of impressive fuel mileage posts for the 1150RTs. But, no way mine sees 40mpg at 85mph. That kind of speed plus the Techlusion box adding fuel, I don't think there is much upside.

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Yeah, I tweaked the BBS screws. It was idling so bad I turned them all the way in, then backed them out 2 1/2 turns. From there I adjusted them to get the best idle I could. Both are 1/4 from each other at ~2 3/4 turns out from the stops.

 

They are quite a way out.

Have you removed them and given them and their related galleries a REALLY good clean out with carb cleaner and maybe some cotton wool buds, then blow them out with an air gun.

Check the condition of the BBS O rings..

If all is good, refit and start again. I wonder whether you have an issue with a problem in this area.

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Hi dr,

 

I'm able to ride my 02 RT, been commuting all week. With the pink CCP plug the bike idles like crap. Top end is great just won't idle. I switched back to the yellow plug jumper and it idles better but around 4200 rpm the engine vibrates pretty bad.

 

I finally found the time to throw it on the lift and take a look. I measured 375mV on the TPS. I don't see how to disconnect the 02 sensor or I would try it.

 

After switching back to the pink plug I cleaned the BBS, they were a bit carboned up but not terribly bad. It seemed to help at first but no real difference. Bike still idles like crap. I did notice the BBS rubber seals are looking a tad rough. Methinks I will stop by the shop and grab some news ones. I also disabled the techlusion so I can just rule that out.

 

TIA

 

Indy

02 R1150RT

 

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roger 04 rt

Indy,

Since you had a Techlusion (which model?), it is very likely that your O2 sensor is unplugged and that is the problem.

 

The O2 sensor connector is a 0.5" diameter 1.5" long cylindrical connector, located under the fuel tank, tie-wrapped to the frame, to the right of the alternator. You can usually find a picture in the Techlusion manual, here: http://www.tficontrollers.com/instructions/950111031.pdf.

 

Most likely, if you plug it back in and go for a ride, the idle will improve but you may need to get a gauge connected and balance the TBs.

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Morning Indy

 

As Roger says it depends on the type of Techlusion you have.

 

Most Techlusions that were put on the 1150 did connect to the factory o2 sensor but there was still the older (fuel nanny type) available that didn't use the o2 sensor.

 

With the Techlusion involved (assuming you have an o2-using Techlusion model) there are (2) o2 connections to worry about. One from the o2 TO the Techlusion pig tail & the other going from the Techlusion to the factory wire harness 02 plug (under R/H rear of the fuel tank).

 

Just disconnecting one connector might not show you what you need to see.

 

You might have to unbolt the rear of the fuel tank & lift it slightly to disconnect the Techlusion from the factory o2 plug.

 

If you disconnect the Techlusion from the R/H fuel injector connection, or disconnect the Techlusion black ground wire then all you have to disconnect is the Techlusion from the factory o2 plug. (that will run engine with no o2 input)

 

If you want to disable the Techlusion & go back to factory o2 control you will have to unplug the factory o2 sensor from the Techlusion, then unplug the Techlusion from the bike side factory wire harness o2 connection, then plug the o2 sensor pig tail directly into bike side o2 wire harness plug.

 

See pix below for o2 sensor plug (just lift ears slightly to pull connector apart)

1150%2002%20sensor_zpsevc1k3wz.jpg

 

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Oh, I see it. The one running right next to the spark plug wire.

Let me move the tank so I can reach it and get back to you

 

Thanks

 

Indy

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Ok, I re routed the plug wire and totally disconnected the techlusion, it's out of the equation. The idle seems smoother with the plug wire re routed and with the O2 plugged in, but it still hunts. Unplugging the o2 sensor makes the idle even better. Hunt is not as pronounced as it is with it plugged in.

 

Another twist, it takes big adjustments on the BBS's to make any idle speed diff. Half a turn or more.

 

Indy

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Afternoon Indy

 

That sounds like you might need to remove the BBS screws then clean the screw tips & clean the air passages/screw seats under the BBS screws.

 

Caution: use o2 sensor safe & cat converter safe cleaner in the throttle body BBS seats & air passages.

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I would get some spray carb cleaner and remove the throttle bodies and give them a really good cleaning and inspect for air leaks then install with BBS set out 1-1/4 turns and do a TB sync and see what you got. No way would I re-install the Techlusion. There are much better ways to obtain a better air fuel ratio, just ask Roger. Oh, has anyone adjusted or played with the throttle body stop screws?

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I pulled the BBS screws out last night and cleaned them and where they fit into the TBs. Used B12 chemtool. I did notice the rubber seals are looking a tad frayed. I can see tiny strands. I think I'll run over to the shop and see if they have replacements.

 

I do notice the idle is worse at higher temps than from a cold start.

 

BTW, I did a quick TB sync and they are dead nuts on at > idle. I can get the idle balanced with the O2 sensor disconnected. Screws are about 2 turns out.

 

Thanks

 

Indy

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With 93k miles, your throttle body shafts and bushing may be worn. This will allow an air leak at the throttle plate shaft. That along with worn out o-rings on the BBS would make idle adjustment difficult and throttle sync at off-idle difficult. Have you rebuilt the throttle bodies, or checked for worn shafts?

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I pulled the BBS screws out last night and cleaned them and where they fit into the TBs. Used B12 chemtool. I did notice the rubber seals are looking a tad frayed. I can see tiny strands. I think I'll run over to the shop and see if they have replacements.

 

I do notice the idle is worse at higher temps than from a cold start.

 

BTW, I did a quick TB sync and they are dead nuts on at > idle. I can get the idle balanced with the O2 sensor disconnected. Screws are about 2 turns out.

 

 

Afternoon Indy

 

If you can get the idle, & above idle, balanced then it sounds like you don't have any major intake air leaks.

 

As a rule things like intake air leaks, BBS "O" ring air leaks, or throttle shaft air leaks cause the BBS screws to have to be turned in farther to compensate not out where yours seem to need to be.

 

You might be fighting some fueling issues if it still hunts at idle.

 

Maybe try removing fuse number 5 for about 3 minutes to clear the old fueling learned offsets then riding the bike a bit to clear the o2 sensor & clear the cylinder out.

 

Just moving the o2 sensor pig tail away from that lower R/H spark plug wire might be enough to clean the idle up after riding for a few miles.

 

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roger 04 rt

Following this thread with interest, when you say the idle hunts, what is the rpm range? (E.g. 1000-1200 rpm)

 

If you crack open the throttle, at what rpm does the hunting stop?

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Yes. The rpms drop below 1000 and when it just about stalls the rpms rise to around 1300 and smooths out. If I crack the throttle it's smooth above say 1200 rpm. It gets worse as the engine temp increases.

 

New BBS screws will be here Tuesday. Cost a whopping $15 😃

 

Indy

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If you could borrow a GS-911 we might be able to figure this out faster. Any chance of that?

 

That would be nice, but the odds are not good.

 

So, as of now I'm in a bone stock config running the pink CCP with no add-on's. New plugs and plug wires, recent valve adjust and TB sync.

 

During ride in today I noticed it backfires a lot on decel and surges around 3000-3200 rpm. Idle when I parked seemed a tad better, ranged from ~1000-1300 rpm, didn't feel like it was going to stall. The temp is around 56 degrees, so it's fairly cool which might be a factor(?).

 

I don't know if I'm starting to imagine things, but at cruise speed, 80-85 mph (4200 rpm-ish) I swear I can feel the engine

hunting/surging. If I hold the throttle at a steady rpm, it feels like the brakes are lightly touched then let off repeating every 30 sec's are so. But the rpm never changes.

 

Lol...I left the tupperware off until I can resolve this. Looks funky but WTH

 

Indy- Practicing my "nekkid bike" drawl

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So, as of now I'm in a bone stock config running the pink CCP with no add-on's. New plugs and plug wires, recent valve adjust and TB sync.

 

During ride in today I noticed it backfires a lot on decel and surges around 3000-3200 rpm. Idle when I parked seemed a tad better, ranged from ~1000-1300 rpm, didn't feel like it was going to stall. The temp is around 56 degrees, so it's fairly cool which might be a factor(?).

 

I don't know if I'm starting to imagine things, but at cruise speed, 80-85 mph (4200 rpm-ish) I swear I can feel the engine

hunting/surging. If I hold the throttle at a steady rpm, it feels like the brakes are lightly touched then let off repeating every 30 sec's are so. But the rpm never changes.

 

 

 

Morning Indy

 

That "surges around 3000-3200 rpm" is fairly normal for a single spark 1150 with no aftermarket fuel controller. Some do it less & some do it more-- Probably the reason that the Techlusion was originally added.

 

That higher speed surging might just be the wind/air currents effecting the bike as you are riding with no smooth flowing fairings.

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The only reason I futzed with it was to see if I could gain a bit

of fuel mileage. Not a top priority but , just wanted to see. (I get upper 30's at 85 mph hiway commutes)

 

Sorry for the hijack but my '04RT (71k) routinely gets in the mid 40's. And after a recent tuneup trying to find a similar idling/stalling issue (fuel pump relay), this morning, I logged 49mpg!

 

Pretty happy since most of my riding is freeway.

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Well hopefully my new BBS screws come in today so I can install them tonight.

 

Last night I double checked a few things and found that my multimeter battery was low. I was checking the bike battery while running and saw 16+ volts (WTF?) So I checked the meter and the battery was low.

 

Afterwards I double checked the TPS voltage again. This time I measured 330 mV which sounds a little low. The spec I saw says 370-400.

 

just grasping at straws at this point. It may be time to have a shop run a GS911 check on it if the BBS screws aren't the answer.

 

Indy

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Afternoon Indy

 

.330v is a little low for the 1150 TPS, I usually set to .365v on the 1150 (Ma 2.4) system.

 

But the impedance of your meter can effect the TPS voltage so be sure you are using a quality volt meter.

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Afternoon Indy

 

.330v is a little low for the 1150 TPS, I usually set to .365v on the 1150 (Ma 2.4) system.

 

But the impedance of your meter can effect the TPS voltage so be sure you are using a quality volt meter.

 

Thanks D.R.

 

The meter I have is a mid-range Radio Shack unit. So given what you said above I think it's best not to touch anything and let the TBS be as is.

 

My plan of attack tonight is to install the new BBS screws, inspect---again--the TB tubes and such. Then quad check the TB sync.

 

Hopefully I can figure this out soon. If not then I'll have to knock on some local doors to see if I can mooch a GS911

 

Thanks for the help.

 

Indy

 

P.S. before I forget, TB Sync without the Techlusion installed, then install it and see what happens

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Well after installing the new BBS the bike does seem to idle a little better. Doesn't act like it's going to stall, but still *hunts* from around 1000-1300 rpms.

 

Other than the idle the bike runs fine, so I dunno .

I think I'll just ride it some more and see if it gets better or worse. Maybe dump in a bottle of Technron.

 

Thanks

 

Indy

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Hi Indy

Things are going in the right direction.

I notice your mileage as 93000?

Have you checked the throttle body spindles for wear?

I wouldn't be suprised if that is where your eratic idle is coming from.

With the bike idling,just place a finger on each of the cam plates and see if it smooths out. You would probably hear them rattling too at tickover.

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Just to pick off some low hanging fruit, are the plugs in the throttle balance ports still in good shape, or are they old and cracked?

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Hi Indy

Things are going in the right direction.

I notice your mileage as 93000?

Have you checked the throttle body spindles for wear?

I wouldn't be suprised if that is where your eratic idle is coming from.

With the bike idling,just place a finger on each of the cam plates and see if it smooths out. You would probably hear them rattling too at tickover.

 

Hi AndyS,

The TB's look fine, I checked again to make sure and nope, no chatter no wiggles (also saw the Chris Harris youtube vid). The balance plugs are brand new, I just replaced those as well, I do that at every TB balance just because and it's cheap.

 

Methinks for now I'm just going to live with this. A TB rebuild is on my winter todo list.

 

I'll just go through the cheapo route now, new fuel filter and a bottle of Techron to see if that helps.

 

If I ever do find the cause I'll post in a new thread.

 

Thanks

 

Indy

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Progress at last.

Following the words of the Emeritus DR. I went over everything I touched.

I recently updated the timing chain tensioner which had me r&r the left TB.

I guess I didn't seat it 100% , saw a very tiny gap in the compliance fitting to the head.

Reseating the TB helped a bunch but still a very small roughness(hunting).

Now unplugging the O2 sensor makes it purr like a kitten.

 

At least I'm getting somewhere

 

Indy

 

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roger 04 rt

Indy,

 

You said you r&r'd the left TB. What did that involve?

 

Since you found and corrected an air gap I suggest you unplug fuse 5 for 5 minutes, reinstall, key on, throttle rotated fully twice, key off. Then connect O2 and see how it goes,

 

With the air leak you had, an incorrect adaptive value was created. Pulling fuse 5 clears it.

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Indy,

 

You said you r&r'd the left TB. What did that involve?

 

Since you found and corrected an air gap I suggest you unplug fuse 5 for 5 minutes, reinstall, key on, throttle rotated fully twice, key off. Then connect O2 and see how it goes,

 

With the air leak you had, an incorrect adaptive value was created. Pulling fuse 5 clears it.

 

It does not like the O2 sensor plugged in. I just did the fuse number 5 reset. Idle is much better without the sensor plugged in.

 

Indy

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roger 04 rt

Was the bike fully warmed up? If it was, then there's still another issue for you to find. It could be as simple as a defective O2 sensor but this is where a GS-911 data set would really help.

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Was the bike fully warmed up? If it was, then there's still another issue for you to find. It could be as simple as a defective O2 sensor but this is where a GS-911 data set would really help.

 

Yes the bike was quite warn. A good four bars. And yes I'm wishing I could mooche a GS911. Maybe the shop would run a quick check

 

Thanks

 

Indy

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I happened to have a O2 sensor in my garage cabinet from a Ford Exploder we got rid of.

A Bosch 75-1649. Has the same 4 wire pin out, two white one gray and one black. So I pinned it Into the bikes plug and tested and gotta say the idle is steady with it pinned in. I removed it and plugged in the bikes and back to the rough idle.

 

The one I pinned in was just hanging off the side of the bike but the idle is noticeabley better with the test sensor.

 

Indy

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I'm searching for a cross reference for new one so I don't have to pay $200 plus

For a BMW part numbered one. I can't see paying more than $50

 

Indy

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Afternoon Indy

 

There are a number of o2 sensors that will work but most require splicing into & using your existing o2 connector.

 

The Bosch (universal) 15729 fits good but does require splicing into your connector.

 

Caution: NEVER SOLDER the o2 sensor wires as that blocks the external reference air from reaching the o2 sensor.

 

The Bosch 15729 is usually available on E-Bay for about $30.00 or so.

 

Beemer Boneyard also sells a replacement o2 sensor for much less than the BMW dealer.

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Afternoon Indy

 

There are a number of o2 sensors that will work but most require splicing into & using your existing o2 connector.

 

The Bosch (universal) 15729 fits good but does require splicing into your connector.

 

Caution: NEVER SOLDER the o2 sensor wires as that blocks the external reference air from reaching the o2 sensor.

 

The Bosch 15729 is usually available on E-Bay for about $30.00 or so.

 

Beemer Boneyard also sells a replacement o2 sensor for much less than the BMW dealer.

 

Thanks a bunch dirtrider!!!!

 

I picked up a 15729 at O'Reilleys for $63. That did the trick :thumbsup:

Test ride proved it was the sensor. Still needs the techlusion, which needs some readjustment but the idle is steady Betty.

 

Thanks to all for the help, much appreciated

 

Indy

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"Still needs the techlusion"

 

Stop

Do a read of Roger's data and other posts wrt then pm him about

a different management system everyone raves about

usual disclaimer

 

roger 04 rt

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