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vacuum leak or something else

6103 Views 10 Replies 5 Participants Last post by  Bluemeanie
Brief history on my Voyager. Had the infamous vacuum leak at the throttle body, after jumping thru many hoops got it fixed under warranty (new orings). As expected the problem came back, the dealer and Kawasaki were adamant the it wasn't a vacuum leak, so I got a gasket from Thunder and installed it as per the instructions that came with it (leave the orings in place, stick the gasket in and reassemble). I thought it'd come back with no grease and it may have. Fast forward to about a week ago. On a ride I noticed that when coming to a stop the bike would idle around 1200 and then eventually drop (never did that before), then after leaving it sit for about 10 minutes after the ride, when I started it, it wouldn't idle (same as when the vacuum leak was there). If I gave it some throttle it'd start and eventually idle. So I assumed (yes I know how it's spelled, and it may have got me) the leak was back. I ordered another gasket from Thunder and new orings. I installed the new gasket and orings and also greased them with some silicone, then waited 36 hours for the sealer to set. So, today I started it, so far so good, the it behaved for about a 25 mile trip. When I go home I let it sit about 5-10 miniutes, and when I attempted to start it, it wouldn't. So I gave it some throttle and she started, but ran like crap but eventually settled down, it did sound like it backfired and knocked a few times. tho. I let it sit again and took the cover off the throttle body side. Again, it wouldn't start without giving it some throttle, but when it did, it definitely backfired out the throttle body. It eventually settled down again. So I let it sit at least 30 minutes and she started ok. At this point I'm fairly confident that it's not a vacuum leak between the tb and intake, and I'm not looking forward to taking it apart again (not to mention ordering another gasket, orings etc). Anyone have any ideas? At this point I'm at a loss.
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What year is your Voyager?
It's a 2011, currently has 12,200 miles. Original problem was there when the bike was new. Dealer fix was at about 1500 miles, that lasted about 1k, then the dealing with the dealer and Kawasaki started again (including me demonstrating the problem to Kawasaki at Bike Week to which I was told flat out the bike didn't have a problem). I fixed it myself at about 6k. Then this started 2 weeks ago, first I thought maybe I had a bad tank of gas, so rode that out, then it happened again, so that's when I did the new gasket and o rings.
Had a simular problem on my 12 Voyager as far as not wanting to start and running rough after starting for a few seconds. Never did find the problem, they said maybe bad gas. That was at about 5-6000 miles, it now has just under 25,000. Good luck.
It's confirmed, it's a vacuum leak. It's between the intake and heads, at least on the rear cylinder. Seems it is sealed between the throttle body and intake. Sprayed tb cleaner there and while the idle dropped a bit, I could never get it to do it in the same place twice, but when I sprayed back at the head the idle dropped every time.

Where is this screw that holds the throttle cable stop on? My old eyes can't see it.
My 2011. First year in Nevada... did not notice anything much but a couple time the idle would stay high.

Second year moved to Texas... the Voyager sat idle in the new house garage 7 months while I was still living/moving stuff from Nevada.

A few short months after living in Texas the fast idle starting being very notifiable. But not all the time. Then it started becoming ALL the time.

I had a fast idle issue for about 7 months. It would not idle lower than 1,400 rpm sometimes out on the road. It would not go below 1000 on start up or stay at 1,200 rpm.....

Took it to the dealer and of course said "they do that"... and all they did was spray the throttle body with something. It seemed to work for a couple days.

I should note, it would always run fine even when the idle never came below 1,200. No back fire or pop which it has never done so I knew it was not an air intake leak.

I would pull up to a red light and the engine was still going 65 mph....

So... I then saw a couple threads in here about guys talking about sea foam.... I ran two cans through (4 oz to 5 gal). Took about two weeks, but immediately the idle was not as bad. After two full cans the idle has never done it again. I still add 4 oz every other tank of gas. I run cheapest unleaded. But when the idle thing started I had been running 97 octane all the time. Then went to the 93 octane. And still use it.

No idea what was causing it, I am assuming some gunk build up in the injectors or something. It actually runs better than it did when I first got it. I have about 40k on it now ( I think, did not go look)

But I am a sea foam believer now.....
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I usually use 5 oz's of Seafoam every time I change the oil, but I'll add some now just in case. Thanks for mentioning it, also made me think that I should also inspect the throttle body for crud, I know on my 1500 it would crud up on the bottom of the butterfly's.
Waiting for the parts to come in so I can get the leak between the intake and head fixed. Hopefully getting the intake off isn't too bad.
I discovered vacuum leaks on my Vaq in Sept 2011 with about 10,000 or so miles. The leaks were of course between the throttle body/manifold junction but the worse leaks were between the intake manifolds and the heads.

Pulled everything apart and sealed all points...WALA...gone was the poor idle, throttle response and gas mileage.

RACNRAY
I discovered vacuum leaks on my Vaq in Sept 2011 with about 10,000 or so miles. The leaks were of course between the throttle body/manifold junction but the worse leaks were between the intake manifolds and the heads.

Pulled everything apart and sealed all points...WALA...gone was the poor idle, throttle response and gas mileage.

RACNRAY
Did you use something like Form-a-gasket to seal at the heads? I already have the thunder gasket between the throttle body and the intake. I developed a "stumble" in the 1400-1800 rpm range at about 13000 miles. Dealer says it the CT on the back causing it. Yea, right.
Did you use something like Form-a-gasket to seal at the heads? I already have the thunder gasket between the throttle body and the intake. I developed a "stumble" in the 1400-1800 rpm range at about 13000 miles. Dealer says it the CT on the back causing it. Yea, right.
All areas were sealed with ThreeBond 1211.

RACNRAY
Nice to know you used Threebond 1211, that's what I planned to use. Still waiting for the new gasket from Thunder, but may go ahead without it. Don't want to leave it torn apart for too long as I don't have much room to work in the garage so I can see myself loosing screws etc.

I love the car tire causing the problem. That's even better than the "they all do it, it's normal".
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