In desperate need of help to resolve boost issue.
In desperate need of help to resolve boost issue. I'm having issues with my turbo'd ski-doo 1200. The sled runs great until it gets into boost then it falls on it's face. I'm showing 9lbs of boost, good AFR, have pressure tested the coldside for leaks, checked plugs, coils, turbo etc. What am I forgetting?
Basically I have boost, had to pull out a ton of fuel from a known good MAP which tells me I'm not making any power and have the sled running like a stock one with no boost now. The sled does feel like it starts to make power at 1 or 2lbs but anymore than that and it feels like I pulled a chute. I figure with all the experience on here somebody has had to have had a similar issue.
Help please I have a big trip coming up and really don't want to put my stock stuff back on.
Thanks, Carl.
P.S.- I've been trying to figure this out for two weeks, lol.
Basically I have boost, had to pull out a ton of fuel from a known good MAP which tells me I'm not making any power and have the sled running like a stock one with no boost now. The sled does feel like it starts to make power at 1 or 2lbs but anymore than that and it feels like I pulled a chute. I figure with all the experience on here somebody has had to have had a similar issue.
Help please I have a big trip coming up and really don't want to put my stock stuff back on.
Thanks, Carl.
P.S.- I've been trying to figure this out for two weeks, lol.
So after getting some video of the gauges I found the sled was actually quit rich. The back pressure was blowing the waste gate open. I was showing boost on the gauge but it was just hot air as the turbo was way past it's efficiency range. Just thought I would update in case anyone else had a similar problem.
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It's a 2010 skidoo renegade 1200. It's a custom kit that put together. I thought it was fixed but it isn't. I didn't build the header and I think the header/waste gate is causing my issues. A 9lb spring is opening the gate at 0lbs. I put the stiffest spring in it and it opens at 4lbs. With my boost controller on it opens at 7lbs. Problem is that as soon as the gate opens I loose all power. Sled pulls fine until the gate opens. I can also build way more boost after the gate opens, just doesn't make power. I've tested/checked everything and tried two different gates. I think the waste gate is too close to the one header tube and its only bleeding boost from the one cylinder and not the other two. I'm going to relocate the gate to the exhaust housing to see if it clears up.
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Verdad Gallardo I have no way to measure back pressure yet. I've rebuilt the hot side and repositioned the gate just have to wait for my new clutch to test. So the sled makes great power until the waste gate opens. As soon as it opens I loose all power. It doesn't sound like it's opening fully. Kind of sounds like it's fluttering. Will go on the dyno next week if I don't have it figured out by then.
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Joined: Nov 2003
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From: Norn Iron
When you say it loses all power.
Do you mean a total engine kill ? a power reduction ? failure of power to climb ?
What is fueling like ? Does boost stay at a certain level ? spark timing ?
And a wastegate is dynamic, it isnt just a simple open or close by a fixed amount. It will be a variable opening, and sometimes it can sound strange.
Do you mean a total engine kill ? a power reduction ? failure of power to climb ?
What is fueling like ? Does boost stay at a certain level ? spark timing ?
And a wastegate is dynamic, it isnt just a simple open or close by a fixed amount. It will be a variable opening, and sometimes it can sound strange.
When you say it loses all power.
Do you mean a total engine kill ? a power reduction ? failure of power to climb ?
What is fueling like ? Does boost stay at a certain level ? spark timing ?
And a wastegate is dynamic, it isnt just a simple open or close by a fixed amount. It will be a variable opening, and sometimes it can sound strange.
Do you mean a total engine kill ? a power reduction ? failure of power to climb ?
What is fueling like ? Does boost stay at a certain level ? spark timing ?
And a wastegate is dynamic, it isnt just a simple open or close by a fixed amount. It will be a variable opening, and sometimes it can sound strange.
Will draw the lines out when I have access to a computer. I've ran anywhere from 6-15lb spring. The gate starts to open at 0lbs every time. I put my laptop on it tonight and it wants to make boost at 5000rpm at 10% throttle. Just poking down the trail I looked at the exhaust and it was glowing red. I'm starting to think the shop that shimmed my valves may have the timing off a tooth or so. No way this thing should want to make boost at 10% throttle. Maybe fuel is getting ignited in the header causing the early spool and glowing exhaust?
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Joined: Nov 2003
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From: Norn Iron
Will draw the lines out when I have access to a computer. I've ran anywhere from 6-15lb spring. The gate starts to open at 0lbs every time. I put my laptop on it tonight and it wants to make boost at 5000rpm at 10% throttle. Just poking down the trail I looked at the exhaust and it was glowing red. I'm starting to think the shop that shimmed my valves may have the timing off a tooth or so. No way this thing should want to make boost at 10% throttle. Maybe fuel is getting ignited in the header causing the early spool and glowing exhaust?
Again I ask about ignition timing. You need to know what's going on here, not just assume it is ok.
But at 5000rpm, it wouldnt surprise me that there is enough exhaust energy to spool the turbo
But it makes no sense at all that the w/g would be opening at 0psi if you have 15psi springs installed
Again I ask about ignition timing. You need to know what's going on here, not just assume it is ok.
But at 5000rpm, it wouldnt surprise me that there is enough exhaust energy to spool the turbo
But it makes no sense at all that the w/g would be opening at 0psi if you have 15psi springs installed
But at 5000rpm, it wouldnt surprise me that there is enough exhaust energy to spool the turbo
But it makes no sense at all that the w/g would be opening at 0psi if you have 15psi springs installed
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Joined: Nov 2003
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From: Norn Iron
There is no way to adjust ignition timing on the factory ecu. I've verified cam timing and it's correct. I performed a leak down test tonight and although it passed according to the gauge I had some leakage out the exhaust. I'm going to verify that I have the correct valve clearance and hope I don't have to pull the head for a valve job.
There may be no way to adjust, but that still doesnt mean it is doing what you want, what you expect, or what you think.
Hence confirming it isnt doing anything strange.
I highly doubt the problem is some leaky exhaust valves as that wouldnt explain the w/g opening at 0psi