New Fuel Pump, Car won't start
#1
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New Fuel Pump, Car won't start
Hello,
Car is a 1997 Miata with a BP4W swap, MS1 that was converted to MS2.
I roasted a walbro 255 fuel pump at the track, or so I thought. I was getting fuel starvation in a corner so I pulled in to fuel up. Went out again and the same thing happened after a few laps. Car then died in the paddock and the pump wouldn't prime. Towed the car home and turns out I blew the fuse. But the fuel pump never sounded right when priming and I was getting weird idle issues and hesitation around 5k so I decided to throw in a new Walbro anyways. But before swapping pumps I did start the car and it seemed to run how it did before, but I didn't drive it.
New pump is in and I put in an NA6 fuel level sensor since my current one was sometimes unreliable (car is an NA8 but I made the different arm work). I can hear it priming and I can confirm there is fuel in the feed and return line from/to the tank. The car will crank but won't fire.
I went onto tunerstudio to get some composite logs but here's where things get really weird... Right away I noticed my throttle position on Tunerstudio was reading 143.4%. Coolant temps is 180 degrees, but the car hasn't run for days. And I saw some white smoke come out of the windshield HVAC vents... I'm dumbfounded what would go wrong? All I did was swap in a new Walbro 255 and swap in the NA6 fuel level sensor. Prior to that none of these things were happening! I didn't end up getting any composite logs, once I saw smoke I said "Nope, nope noooope..."
Any pointers on where I should start looking? If you guys need composite logs I'll get some.
Thanks
Car is a 1997 Miata with a BP4W swap, MS1 that was converted to MS2.
I roasted a walbro 255 fuel pump at the track, or so I thought. I was getting fuel starvation in a corner so I pulled in to fuel up. Went out again and the same thing happened after a few laps. Car then died in the paddock and the pump wouldn't prime. Towed the car home and turns out I blew the fuse. But the fuel pump never sounded right when priming and I was getting weird idle issues and hesitation around 5k so I decided to throw in a new Walbro anyways. But before swapping pumps I did start the car and it seemed to run how it did before, but I didn't drive it.
New pump is in and I put in an NA6 fuel level sensor since my current one was sometimes unreliable (car is an NA8 but I made the different arm work). I can hear it priming and I can confirm there is fuel in the feed and return line from/to the tank. The car will crank but won't fire.
I went onto tunerstudio to get some composite logs but here's where things get really weird... Right away I noticed my throttle position on Tunerstudio was reading 143.4%. Coolant temps is 180 degrees, but the car hasn't run for days. And I saw some white smoke come out of the windshield HVAC vents... I'm dumbfounded what would go wrong? All I did was swap in a new Walbro 255 and swap in the NA6 fuel level sensor. Prior to that none of these things were happening! I didn't end up getting any composite logs, once I saw smoke I said "Nope, nope noooope..."
Any pointers on where I should start looking? If you guys need composite logs I'll get some.
Thanks
#3
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More info:
I checked the wiring harness for my ECU and I noticed the Ground wire on Plug #3 melted and shorted to the Red/Blue wire that turns out to be the TPS wire. So I guess that's why my TPS position is wonky. But what would of caused that?
I checked the wiring harness for my ECU and I noticed the Ground wire on Plug #3 melted and shorted to the Red/Blue wire that turns out to be the TPS wire. So I guess that's why my TPS position is wonky. But what would of caused that?
#5
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Yeah you've got some other critical electrical issue. TPS is supposed to be 5v. Did you loose an alternator? Wiring short? Ground missing or broken? Check all other systems, brakes, blinkers, etc.
#6
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Found out what was wrong with the help of Matt from DIYautotune and my friend using Matt's advice to help pinpoint the issue.
Turned out the IAT wires either melted from track heat or rubbed through the crank pulley. That shorted and blew the fuse for the fuel system. As well as shorting the ground wire for plug #3 for my ecu. IAT is all fixed and everything seems to be working fine.
Thanks to Matt from DIYautotune for his time, always helpful advice from him whenever I have issues.
Turned out the IAT wires either melted from track heat or rubbed through the crank pulley. That shorted and blew the fuse for the fuel system. As well as shorting the ground wire for plug #3 for my ecu. IAT is all fixed and everything seems to be working fine.
Thanks to Matt from DIYautotune for his time, always helpful advice from him whenever I have issues.