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Discussion Starter #1
Hi all! First post.
A video says a thousand words:
Sorry its plee for help. R6 is struggling to run, and I'm out of ideas :(
Plugs changed, and checked firing.
Injectors are firing in order patterns look good.
Fuel pump priming OK.
No fault codes.
Checks coil pack etc in diag mode all heard clicking.
Next check is to get a compression tester on it, fingers crossed.
Any ideas welcome
 

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Had the throttle bodies out lately? Check the boots and that they're fully seated. Also make sure the rats nest of vacuum lines are all connected. These motors will not even remotely tolerate a vacuum leak.
 

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Discussion Starter #3
Yeah I've had it all out, I'll recheck everything and reseat the throttle bodies. I'll be doing a compression test whilst they are off aswell, but to confirm it's not anything more serious.
 

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Discussion Starter #4
Compression test is good on all cylinders. Took the quick shifter off today just to check it wasn't interfering. All headers get hot when trying to start so looks like all cylinders are firing, it just won't run.
 

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By the sounds of it in the video, I would've guessed at something mechanical. But your compression tests are good and you've checked vacuum so we're presumably good there.

When was the last time it was run?
Have you swapped out the fuel?

Review this information...

Review these instructions here...
  • Clean up your choke assembly so that it moves freely, consistently, hot or cold. Avoid using brake/carb cleaner as they damage plastics/silicon/rubber.
  • Completely back-off the throttle plate screw, so the throttle plates are closed. (look at the base of the throttle plate screw, not at the plates)
  • Adjust auto choke screw for a ~2,000 RPM cold idle. (may have to pre-adjust that screw before crank)
  • After warm-up, use the throttle plate stop screw to adjust idle back to ~1,400 RPM.
NOTE: The auto choke system relies on cooling system pressure... so a bad thermostat (internal leak) or bad radiator cap will contribute to malfunction.

Provided that your maximum throttle reads correctly (at least 97 if memory serves) you can avoid flooding the engine after extended cranking by entering flood clear mode. Key on, kill switch off. Max your throttle. Kill switch on. Start cranking. Holding the throttle max while cranking, tells the ECU to "deactivate" the fuel injectors. So all it's running are the spark plugs. That clears the engine. If your max throttle is too low, the engine will try to start... and you'll need to be damned quick on the kill switch to keep from over-revving your engine.
 

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Discussion Starter #6
I have a theory, bare with me:

Added a small amount of fuel direct to the throttle body

Proved fuel pump is working

I think the fuel pump isn't delivering the fuel at the right pressure. Manual says 46psi. I'll rig a pressure gauge tomorrow and update.

Proved injectors are working
 

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Fuel pressure regulator is vacuum-operated. Simply pull the vacuum line (plug the line) and that should cause the pressure regulator to minimize the amount of fuel going back through the return line.
 

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Discussion Starter #8 (Edited)
Sorry Intuit, forgot to mention it's a 13s there is no fuel return line, also it doesn't have a choke, the start fuel mixture is enriched directly via the ECU.
 

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Discussion Starter #9
Fuel pressure direct from the tank isn't even reaching 1 bar. Should be over 3 according to the manual. I'm going to source a new fuel pump. I'll post the results when I've tried a new pump.
 

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Sorry Intuit, forgot to mention it's a 13s there is no fuel return line, also it doesn't have a choke, the start fuel mixture is enriched directly via the ECU.
Fuel is fully electronic on 2nd-Gen as well. (it has MAP and coolant sensors + electronic fuel injection) However there's no way for the ECU to control air... and that's what the auto-choke does on 2nd-Gen. I'd be interested to know how the 3rd-Gens are setup. Do they have an IAC system? Photos? (or better yet, a manual)
 
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