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2012 FJR1300A 24,500 miles
My idle speed is at 950 and when I turn the screw in nothing happens. If I back it out, after several turns the idle starts to slow but all the way in it won't go past 950. When I slowly give it a little throttle it will stall the engine but if I crank on the throttle the engine will rev. I checked all the vacuum hoses and I couldn't find any leaks or blockages. I hooked up a throttle body sync tool and the intake vacuum is really low. As you can see in the photo, the highest vacuum reading is 15.75 cmHg and the spec is 250 mmHg. Because of the low idle and the low intake vacuum I haven’t made any adjustments. I recently bought the bike so I don’t have any history on it.
 

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As Russ says, check air box/filter.
Idle screw turned in clockwise should increase RPM.
If you don't know where the sync screws are set, remove them all, careful not to lose the little o-ring, brass washer and spring. Spritz some carb cleaner in each hole and clean off the needles. Reinstall, this time set #3 (the reference) to 3/4-7/8 of a turn out. Install all others the same, then do your sync using #3 for the reference (although technically you can pick whatever one you like as reference, as long as you can get them all the same).
Set idle speed at 1100.
 

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Took the airbox off to look to inspect the throttle body's and installed a a new air filter. I will remove the sync screws and try the carb cleaner. Once I'm done I will post the outcome. Thanks!
 

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2007 FJR A Model
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One other situation I've encountered but you say you don't know the history. Timing chain jumping one tooth on the crankshaft sprocket gives the exact, and I mean exact, symptoms you describe. Any chance this job was done?
 

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I don't any history on the bike and I don't have anyway to contact the previous owner. I bought the bike from a dealer and they gave 100 mile to test the bike. It stalled a couple of times on the 80 mile ride home but it would start right back up so I didn't think it was a big deal.

I took out the sync screws and used some carb cleaner, adjusted sync screws and the idle is at 1150 to 1200 now. I'm still concerned about the low vacuum on the sync tool. It's running about 16cmHg and the spec is 25cmHg (250 mmHg). Has anyone ever synced the throttle bodies and has this low of vacuum? When I did a google search on FJR throttle body sync using the same gage as mine and it was showing 25 cmHg at idle. Now that it is Idling around 1150 I will try to adjust the throttle position sensor tomorrow and see if that helps with stalling when I turn the throttle slowly. If the timing chain skipped a tooth will it hurt the engine if I keep riding it?
 

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One tooth will mean more than likely it won't develop full horsepower at 6000 and above, and it will be noticeable as a flat spot in the power band, may struggle to reach 7000 rpm. 2012 had the redesigned CCT, but it wouldn't hurt to get the latest one.
The only way you can tell if the valve timing is off, is to remove the valve cover and right timing cover to verify the timing marks all line up. In other words, do a valve check.
I don't think adjusting the TPS is going to improve anything with vacuum. The bike has low mileage and has been sitting. Go for a ride and see what happens with wide open throttle at 6000, if it gets flat there, it confirms valve timing likely off.
The other thing you can do is a compression check without taking the bike apart.
Additional question, what is peak vacuum at no load if you rev it to say 3-4000 rpm steady?
 
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I don't think the vacuum went much higher when I ran the bike at I raised the RPM's. I did put the idle was about 1300. I took it on some hi speed runs and I didn't notice any flat spots and the bike never stalled at (1300) Idle. I couldn't find find my compression test gauge so I didn't check the compression yet but going to buy a new one. I still need to check the TPS, readjust the idle speed, check the compression and see how it runs. After I make the adjustments I will let you know what the vacuum is at 3-4000 rpm. Appreciate all your help...Thanks!
 

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In my post above I said that the bike was idling faster after cleaning the sync screws and doing a Throttle body sync. It was about 60 degrees that day, a couple days later when it was 30 degrees out and I could only get the idle up to 1,000 rpm. I haven't had any 60 degree plus days since to see if it will repeat. I did check the vacuum at 4,000 and seems to stay around 14 cmHg. When it was warm out I was getting around 16 cmHg.

I did the compression test and the pressure was really low. The nominal spec in the service manual is 227.6 psi and the bottom of the spec is 197.7 psi. I live in Colorado and the elevation is 6,877 feet so I used a correction factor I found on the internet (7000' .8106). I calculated the minimum 197.7 x .8106 and it came out to 160.3 psi. So per the manual I squirted a teaspoon of oil into the cylinder and retested and it jumped to approximately 190 psi which according to the manual it the ring are not sealing. I did this for all four cylinders and got the same result. The next thing I did was a leak down test on all cylinders, I set the pressure to 100 psi and the loss reading was at approximately 97 psi. I'm confused why the compression reading is low but the the leak down test is only showing approximately 3% loss. I would assume the jumped timing chain could cause low compression because of the intake valve closing at the wrong time. If it is a jumped timing chain why would that cause the compression to jump up 45 psi after adding a tsp of oil?
 

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Your compression is fine, and if all 4 cylinders are within roughly 10% or so of each other, they're good. No way that engine is worn out at 24k. Any time I've checked compression on an FJR, it was roughly a bit more than you're getting (altitude as you say) and every time I put oil in one it would improve significantly. Never saw one at 220 psi, ever.
With regard to the altitude thing, does it also make sense the vacuum readings are low? Perhaps remove a hose and check it there instead of at the sync ports.
I would check every hose for cracks/poor fitting and ensure you don't have a leak somewhere.
BUT, want you to remove the MAP sensor and check that hose and vac nipple are not suffering any crud build-up that may cause the MAP sensor to not provide the proper signal to the ECU. It can cause issues with poor idle and performance. Black thing, two screws on top of throttle bodies, vac hose underneath.

I would doubt anyone has done a valve check on that bike (yet) and would have got the cam chain timing off. But, can you verify this thing accelerates really well past 6-7000 rpm... developing full power, if performance is OK, you don't have a valve timing problem.
 
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The low compression was really bothering me but after doing the leak down test I felt a lot more hopeful. I wonder why the compression PSI specs are so far off in the service manual. I could find any thing for calculating vacuum at high altitude.

I have taken the hoses of the MAP sensor to the throttle body's, they were all clean and in good condition. I put the bike in diagnostic mode and the reading for d:03 was 76 which I believe is the metric air pressure for that day according to the weather. When I applied a little suction to the map the reading would change. After you mentioned the MAP I did the voltage test and it checked low. The spec in the manual calls out a range from 3.75 to 4.25 volts and I was getting 3.095 volts. Unfortunately I can't find a MAP sensor in stock so its going to be a couple to a few of weeks before I find out out if the MAP is the issue.

The only other vacuum hoses I could find that could be leaking are the Idle control unit and they all looked good. The rubber caps for the throttle body sync fitting looked good and I have the sync tool hooked to the inlets so it should be the source of a leak. I checked the boots and everything looks good all the boots are on and the clamps are tight. Is there any other vacuum lines that other than the ones I mentioned above that I need to check?

I have accelerated past the 7k rpm a quite few times and never notice any performance issues what so ever. Tomorrow I will try connecting the vacuum hose to MAP sensor line and see what the vacuum pressure is. Is there any other place to check vacuum besides the Sync fittings and the MAP sensor hose fittings?
 

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Sounds like you've covered all the vacuum hoses, MAP, etc., valve timing good.
Perhaps it is time to look at that TPS.... maybe make a slight adjustment and try that?
Have you still got idle adjustment range left? One other thing, there is a master idle screw I believe on the wax idle unit that can give you some more range.
 

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Since it was so close to needing the valve clearance's checked I decided to go ahead and pull the valve cover to check the cam shaft alignment. All the valve clearances are in spec and the cam alignment looked good. I checked the timing chain tensioner and it had a blue dot on it. From what I have read on forums I should replace it with one with a green dot. Since the MAP sensor was out of spec on the voltage I'm waiting to do any more troubleshooting for the slow idle till I receive the new one I ordered.
 

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Any dot on the CCT is good and the latest. Green dot may have been a tweak or different supplier, we're not sure. Dots are good.
Regarding your first and last pic, if you view the camshaft from the sprocket (right) side, you will see a vertical line up the face of the #3 cam bearing cap.... below the arrow that is on top of it. It will line up with the hole in the cam lobe and be a better indicator of valve timing. Some have made errors by not looking straight vertical........
 

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With the engine hot I couldn't get the idle above 1100 rpm and the vacuum to go above 15 cmHg. After working on it for quite some time it started Idling too fast and the vacuum went up to almost 22 cmHg. I started it several times and it repeatedly Idle good and the vacuum stay at around 22 cmHg. The next day the Idle and the vacuum are too low and I can't adjust the idle any higher. I have checked the MAP sensor, O2 Sensor, Throttle Position sensor Air Box Temp sensor, Valve Clearance check, ignition coils, installed new plugs, checked ignition timing, checked for manifold leaks and all the readings on the diagnostic page look good. The bike runs great other the slow idle and when I turn the throttle slow it will die. This is the second time I have noticed the idle speed up but after sitting for awhile it went back to idling too slow. Could this be an ECU problem would dirty injectors or a throttle body cause something like this? Any ideas what to look for would be greatly appreciated...Thanks!

Spark Plug Caps Resistance: (#1) 8.83 (#2) 8.54 (#3) 8.82 (#4) 10.41
Ignition Coil Resistance (#1 & 4) Primary 1.7 Secondary 14.2 @ 45°
Ignition Coil Resistance (#2 & 3) Primary 1.7 Secondary 13.81 @ 45°
 

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Discussion Starter #17 (Edited)
I decided to have the Injectors cleaned and flow tested. I drove a 100 miles from Colorado Springs area to Wheat Ridge (Denver area) Colorado. I took them to a place called Fuel Injection Specialist that I found doing a google search. After being flow tested I was told that one 1 out of the 4 injectors is definitely bad (spraying way off to the side) and that a second fuel injector didn't look very good. The fuel injectors are being cleaned now and then will be retested. Chuck the owner of Fuel Injector Specialist said it is almost definitely the cause of my Idle problems so right now I'm very hopeful. I want to say even if this doesn't fix the idle problem I would like to express how great Chuck has been, I asked him a lot of questions and he has given me his time to answer all my questions about the idle problem I'm having. He has gone over and beyond to help. Once I get the injectors back and put back in the bike I will give an update if this has fixed my idle problem.
 
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