Loss of Power Once Warm - FI car
08-26-2016, 06:37 PM
#1
Instructor
Thread Starter
Loss of Power Once Warm - FI car
So I just had my motor rebuilt and I have driven it about 200 miles since. The other day I was driving to a car show at about 85 MPH when all of a sudden the car started to stumble. Oil pressure and temp was normal but every time I stepped on the gas, the car would act like I was running out of gas.
I pulled over, checked things out and could see nothing strange. The car cooled down and then it drove normal again for about 5 minutes. I thought maybe it was the sensitive CSV but the next day I started the car without the CSV connected, drove for 15 minutes and it ran perfectly. Once temp got to 180, the car started stumbling again. the same way as before.
Full tank of ethanol free gas with new tank and fuel pickup installed.
Please help diagnose if you can. Thank you!
I pulled over, checked things out and could see nothing strange. The car cooled down and then it drove normal again for about 5 minutes. I thought maybe it was the sensitive CSV but the next day I started the car without the CSV connected, drove for 15 minutes and it ran perfectly. Once temp got to 180, the car started stumbling again. the same way as before.
Full tank of ethanol free gas with new tank and fuel pickup installed.
Please help diagnose if you can. Thank you!
08-26-2016, 09:27 PM
#2
Race Director
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My first thought is that fuel is not reaching the FI unit and the engine stumbles because the bowl is being run dry.
Look at the engine-mounted fuel pump and check its flow and pressure.
Look also for debris clogging the fuel filter or the fuel inlet to the FI.
An obscure possibility is that the needle/seat which admits fuel is unscrewing itself. If that happens the bowl will fill slowly, too slowly to sustain high speed engine operation. I stress, tho, that this is obscure and unlikely.
Jim
Look at the engine-mounted fuel pump and check its flow and pressure.
Look also for debris clogging the fuel filter or the fuel inlet to the FI.
An obscure possibility is that the needle/seat which admits fuel is unscrewing itself. If that happens the bowl will fill slowly, too slowly to sustain high speed engine operation. I stress, tho, that this is obscure and unlikely.
Jim
08-27-2016, 02:24 PM
#3
Instructor
Thread Starter
My first thought is that fuel is not reaching the FI unit and the engine stumbles because the bowl is being run dry.
Look at the engine-mounted fuel pump and check its flow and pressure.
Look also for debris clogging the fuel filter or the fuel inlet to the FI.
An obscure possibility is that the needle/seat which admits fuel is unscrewing itself. If that happens the bowl will fill slowly, too slowly to sustain high speed engine operation. I stress, tho, that this is obscure and unlikely.
Jim
Look at the engine-mounted fuel pump and check its flow and pressure.
Look also for debris clogging the fuel filter or the fuel inlet to the FI.
An obscure possibility is that the needle/seat which admits fuel is unscrewing itself. If that happens the bowl will fill slowly, too slowly to sustain high speed engine operation. I stress, tho, that this is obscure and unlikely.
Jim
