Limp Mode Help
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Teching In
Joined: Oct 2018
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Limp Mode Help I have a 67 Camaro with an LS2 in it. Ricks notched tank, ricks tube sender, Walbro pump, and Vette regulator. Pretty simple setup. Drove the car over 1000 miles this summer without issue. The other day while driving on the highway the car went into limp mode. I have driven the car on longer trips and in hotter weather without issue. I cycled the key a few times and drove it off the highway to a safe place to check it out. Couldn't find anything wrong. Oil level fine, temp at 180, gas gauge read 1/2 full. Put in 8 gallons of gas and drove it another 100+ miles home issue free. I have two codes PO461 and PO463 showing up. If I remember correctly, they have been on since day1. My fuel sender is wired right to my gauge cluster, not to the ECM. Which I think is why I see these error codes. Would these codes trip the ECM to go into limp mode? Possibly the fuel sock was starved somehow and ran low on fuel. I am going to pull the tank out and check the sock and see where it is in regards to the bottom of the tank. What is the cheapest way to turn off these codes for good? All I can do with my scanner is clear the codes. Trying to avoid going to the tuner to have him disable them.
Thanks for the help
Thanks for the help
Thread Starter
Teching In
Joined: Oct 2018
Posts: 5
Likes: 0
Good idea I will check with them. So I can handle this myself in the future I know HP tuners is an option. Damn is it expensive. What other options do I have so I can do it myself? Do you think those codes would lead to the car going into limp mode?
Teching In
Joined: Jul 2021
Posts: 27
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Hard to say - doesn’t seem like fuel sender state would be worthy of limp mode to me. I don’t believe I’ve ever had to delete those on any of my swaps.
Just to be clear - when you clear these codes it is no longer in limp mode? Do any other codes pop up when you scan with it in limp mode? Clogged fuel filters may lead to issues, I would think any restriction in the system would cause excessive heat and low pressure after a clogged filter (restriction). Do you have a fuel pressure gauge you can toss on the rail?
I used to have fuel boiling issues in my 6.0 swapped c1500 - kind of the only thing I can think of that jives with some of your symptoms. Usually it would throw a lean code though. It would sound like **** too, not just down on power. Would almost always see it 1/2 mile up the grapevine in so cal and only in warm-hot weather. A lot plays into fuel boiling - fuel level (less fuel = less volume and quicker heating), fuel pressure (less pressure = lower boiling point).
Just to be clear - when you clear these codes it is no longer in limp mode? Do any other codes pop up when you scan with it in limp mode? Clogged fuel filters may lead to issues, I would think any restriction in the system would cause excessive heat and low pressure after a clogged filter (restriction). Do you have a fuel pressure gauge you can toss on the rail?
I used to have fuel boiling issues in my 6.0 swapped c1500 - kind of the only thing I can think of that jives with some of your symptoms. Usually it would throw a lean code though. It would sound like **** too, not just down on power. Would almost always see it 1/2 mile up the grapevine in so cal and only in warm-hot weather. A lot plays into fuel boiling - fuel level (less fuel = less volume and quicker heating), fuel pressure (less pressure = lower boiling point).
Last edited by smog_exempt; Oct 5, 2022 at 11:10 PM.
