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2016 1200 Renegade X
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Starting a thread to work out my issue. I bought this sled and knew it had some issues. I have rebuilt the top end, replaced the Nun and a few other small things. See thread here: http://www.dootalk.com/forums/topic/1144441-my-rebuild-project/ I put 400 Km on the sled last winter after the rebuild. and had a few hicups on one trip with fuel delivery, but found the tank pick-ups were not in the proper locations.

When cold the sled will idle low on start up and backfire every once in a while. The lights will turn on and off too. Once warm this goes away and it runs fine. I have had it backfire when slowing to a stop on the trail.

Fast forward to today: Got my TPS reset today. Was not my issue. The tech said the TPS was fine, but reset it anyhow. The PTO cylinder would periodically stop firing and start again. He indicated either a fuel issue or a ignition issue. He believes ignition as it backfires when it starts firing again. Only seems to do it below 4000 rpm. This is why he thought it might be a fuel issue, low speed injector. They offered to trace it and work on it. I said thanks and loaded it up to bring it home. I have ordered a used coil of ebay, I'll see if that helps.
 

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Check fuel pressure and fuel flow from the injectors, and voltage at the battery. These are three easy things to rule out. Other problems will take further effort.
 

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Here is a short list:

- Fuel Pressure?

- Fuel flow?

- Reeds: OEM or aftermarket?

- Exhaust: OEM or aftermarket?

- Air Intake (airbox): OEM or aftermarket/pods?

- Idle rpm?

- Voltage at the battery on idle?

- Calibration? (see your BUDS report for the part#)

- Air/Fuel ratio at idle and below 4000 rpm?

Not meaning to make things complicated, but the stock tune was designed with stock components and a well running engine. Any change to the components can change the intended tune.
 

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Daag, what do you mean by calibration and can I see this using the candoo?
 

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That's probably sarcasm.
2016 1200 Renegade X
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21,406 Posts
Answers are below.

Here is a short list:

- Fuel Pressure? Unknown
- Fuel flow? Unknown
- Reeds: OEM or aftermarket? VForce
- Exhaust: OEM or aftermarket? OEM
- Air Intake (airbox): OEM or aftermarket/pods? OEM
- Idle rpm? 1800
- Voltage at the battery on idle? Unknown
- Calibration? (see your BUDS report for the part#) no clue what this means. Not given BUDS report.
- Air/Fuel ratio at idle and below 4000 rpm? No clue.

Not meaning to make things complicated, but the stock tune was designed with stock components and a well running engine. Any change to the components can change the intended tune.
 

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Thanks for the answers. There are a lot of unknowns that would take a great deal of effort from an expert tuner at $200/hour to work out.
 

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That's probably sarcasm.
2016 1200 Renegade X
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21,406 Posts
Discussion Starter · #7 ·
The coil and plug wires have arrived. I'll try and get some time to swap them out and see what happens.
 
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That's probably sarcasm.
2016 1200 Renegade X
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21,406 Posts
Discussion Starter · #8 ·
Tonight I pulled it off the trailer, and into the garage. Haven't touched the coils, but it is running better, fewer backfires and it was idling great. No time to do any work tonight.
 

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Another thing to check is the tps plug wires. Sometimes they will rub through the insulation and start shorting the tps. It's the male end that plugs into the tps.
 

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That's probably sarcasm.
2016 1200 Renegade X
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21,406 Posts
Discussion Starter · #10 ·
Swapped out the coil and plug wires today, no change. I have an inline spark tester, maybe I'll hook that up next and just see if is dropping the spark.

TPS wires are fine.
 
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napa relay or any other is fine
 

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Swapped out the coil and plug wires today, no change. I have an inline spark tester, maybe I'll hook that up next and just see if is dropping the spark.

TPS wires are fine.
Great idea on swap and the spark test!!! The advantage of old sleds is having affordable replacement parts :)

There is also nothing wrong with using an alternate plug to shorten the gap. Don't tell anyone, but I break the NGK rules and regap the ECS plugs to 25 thou. It really isn't a great idea to doo this on an ECS plug, but I also know that most people won't go out to buy difference plugs just to try this simple change.

In any case, you should be aware that the calibration for the 04 SDI is in its own play park with backfires. While it has an interesting calibration for power like a gazelle on steroids, everything need to work well for it to avoid engine failure. Low fuel pressure or partially clogged injectors or a TPS problem or a twisted in-tank fuel line are not acceptable for a 2004 calibration.

There is also a factual and BRP documented midrange that can cause a lean failure or even detonation. So if you lend your sled out to someone and tell them to ride with a conservative throttle, you may in fact be spelling out a disaster recipe for your sled and you will be the only person to blame because you have been worn :)

If you make sure everything is in order, then it will be a fun season. Otherwise it can turn into chasing after ghosts.
 

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That's probably sarcasm.
2016 1200 Renegade X
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21,406 Posts
Discussion Starter · #16 ·
I don't lend my sled.

I plan to pull the injectors and get them cleaned and tested at a local shop. Interestingly, if I run normal plugs, they foul. I have been running NGK Iridium plugs and have had no issues with them. I did adjust the oil pump a touch as it was over oiling by a mm or so.
 

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If you have the oil pump on spec, be certain the ECM never thinks there is cause for concern and dumps fuel at the problem. Otherwise the oil supply can easily be cut in half when it actually needs it the most. Thank god for the electronic oil pump on the ETEC.
 

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That's probably sarcasm.
2016 1200 Renegade X
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21,406 Posts
Discussion Starter · #19 ·
try changing voltage regulator
That's on my list of things to do, but further down the list as I don't have access to another to swap out. I'd have to buy one.
 
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