yellow light and red temp light when I let off throttle?

[sledfvr]

I'm getting the temp light and the oil can light when I let off the throttle in boost. It momentarily shuts the sled off for 1 second and then comes back to life. If I cruise at very low boost under 3psi and chop the throttle it doesn't do it. Sled runs great otherwise. There are no codes either? I checked to make sure throttle bodies didn't blow off.

 

[FLYBYU]

Sounds like loose connections. Throttle override. Both lights at the same time, that's weird.

 

[sledfvr]

TORS is bypassed. I'm wondering if my prologger is partly the culprit, I think the sensor is going out and showing lean and the prologger opens the wastegate to prevent engine damage. Not sure, but I will try a new sensor. I don't know why that would throw the lights, but it acts like it's shutting the sled off. Any other ideas?

 

[FLYBYU]

That wouldn't cause it to cut out. Opening wastegate yes. What wastegate do you have? Bypass prologger. Prologger tied into ecu? I didn't think they tie into ecu. Are you having uncontrollable boost? If anything, it goes rich when letting off throttle. What fuel controller are you using?

 

[sledfvr]

You're right I meant it opens the wastegate. It's a boost-it kit. The sled runs on the stock system and the boost it has external injectors that add fuel with boost/rpm's. I put a rev fuel tank on it this summer and put a small fuel pump on to feed the Impulse surge tank. I wonder if the return on the rev tank is too small and is pressurizing the system causing it to be rich when letting off the throttle?

 

[FLYBYU]

A smart thing to do here is to have a fuel pressure gauge inline going to the fuel rail. I learned my lesson with chasing my tail as my fuel pressure regulator was failing causing all kind of running issues. I'm not familiar with the boost it system. I have the full impulse tank and surge tank. My fuel return goes back to the surge and one line out of the surge tank goes back to tank. My surge is always full. I have the stock apex fuel pump filling the surge tank.

 

[sledfvr]

I will put a fuel pressure tester on it tomorrow. Thanks for the quick replies.

 

[TurboTime]

A smart thing to do here is to have a fuel pressure gauge inline going to the fuel rail. I learned my lesson with chasing my tail as my fuel pressure regulator was failing causing all kind of running issues. I'm not familiar with the boost it system. I have the full impulse tank and surge tank. My fuel return goes back to the surge and one line out of the surge tank goes back to tank. My surge is always full. I have the stock apex fuel pump filling the surge tank.

X2, that sounds like the culprit..

 

[sledfvr]

fuel pressure is 48psi when pump is on and drops to 40 when it shuts off. It holds 40psi when off. If I pinch the line it climbs steadily. Seems to be working, but the 48psi running is high, right?

 

[FLYBYU]

way too much fuel pressure. 38 is idle

 

[sledfvr]

strange, I wonder what is causing the high idle pressure?

 

[FLYBYU]

Fuel pressure regulator or your small return to tank. Just for test run the return to a gas can and see what pressure is at idle.

 

[FLYBYU]

If it holds that means it's not stuck open. That's good. I think your small return is the culprit. Like I said before, my return goes back to surge tank to avoid all this. Surge tank overflows back to tank. That's how Paul wanted it. Surge tank always stays full. If your small pump doesn't keep up with your high pressure pump, your sucking surge tank low. Do you see the benefits of having your return going to surge tank?

 

[sledfvr]

This is a full Impulse setup, same as yours. I just took off my aluminum tank due to cracking. So I do have a surge tank and mine goes back to the surge tank like yours and then from the surge tank to the main fuel tank. I pulled the return line off the main tank and ran it into a can and it didn't drop the fuel pressure at all, so its not the fuel return.

 

[FLYBYU]

So then your fuel pressure regulator is stuck closed. It's holding fuel which is caused by it not opening all the way up. Somebody else can chime also but that will vary afr alot. You can pinch return line and you will see pressure go up as it builds pressure just like it would do if fpr was partially closed. Actually the culprit of my fpr going bad was after I installed my surge tank and my high pressure fuel pump failed shortly after do to aluminum shavings in it from surge tank and obviously put some in my fpr also.