Engine suddenly won't run!?
#1
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I tried to go for a drive yesterday and discovered the engine won't run properly. My engine has been running well up to then and I was really surprised to have this problem. Would you please help me work through this?
So basically, I can get the engine started and it'll warm up at idle OK. The engine dies when I apply or remove throttle at anything but very gentle rates. I'm getting AFR readings all over the place and I first thought my Innovate LC2 O2 was causing the problem. I rewired the LC2 on Saturday so it was directly connected to the battery via a relay because I'd been having problems getting consistent readings from it. Then yesterday I tried driving the car for the first time and had this trouble, which made me think the O2 sensor was continuing to malfunction.
But today, I turned off EGO correction to take the O2 sensor out of the loop. The LC2 appeared to generate correct AFR readings but the engine still won't run. To confirm, I removed power to the LC2 by disabling the switch line to the relay. I briefly ran the engine like this while seeing the same results. That implies to me that the problem lies elsewhere.
Any ideas what's going on? I've uploaded my tune and a log file to see if anything looks off.
So basically, I can get the engine started and it'll warm up at idle OK. The engine dies when I apply or remove throttle at anything but very gentle rates. I'm getting AFR readings all over the place and I first thought my Innovate LC2 O2 was causing the problem. I rewired the LC2 on Saturday so it was directly connected to the battery via a relay because I'd been having problems getting consistent readings from it. Then yesterday I tried driving the car for the first time and had this trouble, which made me think the O2 sensor was continuing to malfunction.
But today, I turned off EGO correction to take the O2 sensor out of the loop. The LC2 appeared to generate correct AFR readings but the engine still won't run. To confirm, I removed power to the LC2 by disabling the switch line to the relay. I briefly ran the engine like this while seeing the same results. That implies to me that the problem lies elsewhere.
Any ideas what's going on? I've uploaded my tune and a log file to see if anything looks off.
#2
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I've done a little more research and I believe I've got a vacuum leak. My boost gauge isn't showing as much vacuum as it should and the engine is running rougher than it should. That's obviously not a problem with the Megasquirt or the O2 sensor and I'll need to go in another direction. I couldn't find the leak with a quick once over so I'll take a closer look tomorrow.