Running out of fuel
#21
Tweaking Enginerd
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This was with a continental FFS, which IIRC had a circular electrode running down the middle. Designing a system to be fail safe is good engineering practice, you will not convince me otherwise.
#22
Former Vendor
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You're allowing consistently sub-par operation during common crossover events, in exchange for prevention of a hyper-rare edge case. If we're talking about a singular foreign object, it would need to breach two separate filters and get through the pump to even make it to the sensor. If we're talking about a buildup of smaller particles, those particles are going to destroy the injectors anyway, even moreso if you locate the sensor after the fuel rail. So even if that edge case occurred, it would likely cause total fuel system failure regardless of the position of the sensor. Nothing about any part of that decision tree says good engineering practice to me.
If you wanted the best, you would run the sensor in the feed line in parallel with a secondary fuel line, but I don't know that I would want to add the extra failure points in exchange for the microscopic chance of the sensor becoming plugged.
If you wanted the best, you would run the sensor in the feed line in parallel with a secondary fuel line, but I don't know that I would want to add the extra failure points in exchange for the microscopic chance of the sensor becoming plugged.
#23
Retired Mech Design Engr
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I think my DW200 is wearing out in about a year. Purchased from TSE in March 2018 so should not be a knock-off. I am not loosing fuel up top, but it is taking longer and longer to give me a Pre-Start prime.
In theory, OEM will supply my power needs, but they are really expensive. Not an option for OP, however.
Are Walbro, DW, and OEM our only options?
If I go with Walbro 190 LPH, who is the recommended source?
In theory, OEM will supply my power needs, but they are really expensive. Not an option for OP, however.
Are Walbro, DW, and OEM our only options?
If I go with Walbro 190 LPH, who is the recommended source?
#24
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I think my DW200 is wearing out in about a year. Purchased from TSE in March 2018 so should not be a knock-off. I am not loosing fuel up top, but it is taking longer and longer to give me a Pre-Start prime.
In theory, OEM will supply my power needs, but they are really expensive. Not an option for OP, however.
Are Walbro, DW, and OEM our only options?
If I go with Walbro 190 LPH, who is the recommended source?
In theory, OEM will supply my power needs, but they are really expensive. Not an option for OP, however.
Are Walbro, DW, and OEM our only options?
If I go with Walbro 190 LPH, who is the recommended source?
I went with a Walbro 255, I bought it from 5x Racing it was 100 bucks. Its SO MUCH LOUDER than the DW200 but if it lasts longer than 10 months thatll be just super.
#26
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I would seriously consider moving the sensor to the return if it is not already there. I have personaally seen one of these get plugged by a foriegn object. On that install, the sensor was on the return, so the result was an extreme rich (safe) condition. If the sensor had been on the source line, it most likely would have been catastrophic.
We can just enable AFR failsafe which should cut your ignition completely very quickly (I personally have it set to +0.5 AFR error above 100kpa, and to fully cut after 1 second, I would set it to cut faster but I have returnless so heatsoak is a pita sometimes).
#27
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UPDATE: Got the fuel pressure sensor up and running and took a bunch of logs. I have not been able to replicate the fuel pressure loss that I did on the dyno. I maintain a fuel pressure - boost psi < 50psi all the time. I get a small drop as a boost through 25psi. But I don't see a big drop like on the dyno.
But, I didn't up the fuel pressure from the 45psi to a 60 psi on the pressure regulator. Now, interesting thing is that the fuel pressure sensor isn't reading 60psi, it reads about 45psi. So I wonder if when we changed the fuel pressure regulator down to "45" psi, it was actually a lot lower... Could be the real problem to begin with.
BTW, 25psi is bananas.
Also, I HATE MEGASQUIRT. There I said it. Feels good. ******* documentation for the MS3PRO (MSM 0405) states that the backside port has an Analog Input1. WRONG. The ******* "rear option connector" pin D isn't connected the ****. There is no trace going to/from that pin. Christ. So that analog pin1 is actually connected to the main connector pins.
But, I didn't up the fuel pressure from the 45psi to a 60 psi on the pressure regulator. Now, interesting thing is that the fuel pressure sensor isn't reading 60psi, it reads about 45psi. So I wonder if when we changed the fuel pressure regulator down to "45" psi, it was actually a lot lower... Could be the real problem to begin with.
BTW, 25psi is bananas.
Also, I HATE MEGASQUIRT. There I said it. Feels good. ******* documentation for the MS3PRO (MSM 0405) states that the backside port has an Analog Input1. WRONG. The ******* "rear option connector" pin D isn't connected the ****. There is no trace going to/from that pin. Christ. So that analog pin1 is actually connected to the main connector pins.
#28
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UPDATE: Got the fuel pressure sensor up and running and took a bunch of logs. I have not been able to replicate the fuel pressure loss that I did on the dyno. I maintain a fuel pressure - boost psi < 50psi all the time. I get a small drop as a boost through 25psi. But I don't see a big drop like on the dyno.
But, I didn't up the fuel pressure from the 45psi to a 60 psi on the pressure regulator. Now, interesting thing is that the fuel pressure sensor isn't reading 60psi, it reads about 45psi. So I wonder if when we changed the fuel pressure regulator down to "45" psi, it was actually a lot lower... Could be the real problem to begin with.
BTW, 25psi is bananas.
Also, I HATE MEGASQUIRT. There I said it. Feels good. ******* documentation for the MS3PRO (MSM 0405) states that the backside port has an Analog Input1. WRONG. The ******* "rear option connector" pin D isn't connected the ****. There is no trace going to/from that pin. Christ. So that analog pin1 is actually connected to the main connector pins.
But, I didn't up the fuel pressure from the 45psi to a 60 psi on the pressure regulator. Now, interesting thing is that the fuel pressure sensor isn't reading 60psi, it reads about 45psi. So I wonder if when we changed the fuel pressure regulator down to "45" psi, it was actually a lot lower... Could be the real problem to begin with.
BTW, 25psi is bananas.
Also, I HATE MEGASQUIRT. There I said it. Feels good. ******* documentation for the MS3PRO (MSM 0405) states that the backside port has an Analog Input1. WRONG. The ******* "rear option connector" pin D isn't connected the ****. There is no trace going to/from that pin. Christ. So that analog pin1 is actually connected to the main connector pins.
When my pump was going out it wasn't until the pump got warm after running for a while that it started dropping pressure. For the first 20-30 minutes it would usually be fine, then it would start having issues the longer the car was running continuously.
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