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Car wont start after LPFP and HPFP Install

8K views 12 replies 9 participants last post by  blkdrgn 
#1 ·
My friend and I installed the AMS LPFP and HPFP.

1. Installed LPFP and HPFP
2. Started the car and drove it about 1/2 mile and the car died sudden
3. Took out the pump and the yellow and blue connectors were backwards
4. The 15a fuel pump fuse was also blown
4. Swapped them replaced the fuse and drove 1/2 mile again and it died almost the same spot
5. Luckily my friend had a spare stock fuel pump assembly
6. Installed the stock assembly and replaced the 15a fuse.
7. Drove home about 15 miles away. Car seemed fine.
8. Parked the car. Engine off
9. 10 minutes later, drove down a few blocks and turned off the engine.
10. Started the car and it was stuttering.
11. EcuTek DTC Tool said P0301-00 (Cylinder 1 Misfire Detected) and P0300-00 (Random/Multiple Cylinder Misfire Detected).
12. Cleared the logs and car still stuttered
13. Cleared logs again and now I get P0130-00 (02 Sensor Circuit Bank 1 Sensor 1). Car still stuttered.
13. Cleared logs again and now no errors but car wont start.

What should I check next? Do you think the new pumps are bad?
 
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#2 ·
My friend and I installed the AMS LPFP and HPFP.

1. Installed LPFP and HPFP
2. Started the car and drove it about 1/2 mile and the car died sudden
3. Took out the pump and the yellow and blue connectors were backwards
4. The 15a fuel pump fuse was also blown
4. Swapped them replaced the fuse and drove 1/2 mile again and it died almost the same spot
5. Luckily my friend had a spare stock fuel pump assembly
6. Installed the stock assembly and replaced the 15a fuse.
7. Drove home about 15 miles away. Car seemed fine.
8. Parked the car. Engine off
9. 10 minutes later, drove down a few blocks and turned off the engine.
10. Started the car and it was stuttering.
11. EcuTek DTC Tool said P0301-00 (Cylinder 1 Misfire Detected) and P0300-00 (Random/Multiple Cylinder Misfire Detected).
12. Cleared the logs and car still stuttered
13. Cleared logs again and now I get P0130-00 (02 Sensor Circuit Bank 1 Sensor 1). Car still stuttered.
13. Cleared logs again and now no errors but car wont start.

What should I check next? Do you think the new pumps are bad?

When installing the LPFP, you likely drained down the fuel tank prior to replacement. How much fuel is currently in the tank? What is the LPFP pressure during the start sequence?
 
#3 ·
Reinstall OEM pumps and flash with stock ROM. Clear the fault codes if necessary and test the vehicle. If everything checks out ok and you are willing to try again, install the AMS LPFP only and run it with the OEM HPFP. If the vehicle runs fine reinstall the AMS HPFP along with the appropriate ROM and test again. Good luck.
 
#4 · (Edited)
I checked and the 15a fuel fuse did not blow so I reinstalled the stock HPFP and the car starts but it's very rough. Stuttering and the DTC is showing P0300-00 Random/Multiple Cylinder Misfire Detected.
 
#5 ·
My friend and I installed the AMS LPFP and HPFP.

1. Installed LPFP and HPFP
2. Started the car and drove it about 1/2 mile and the car died sudden
3. Took out the pump and the yellow and blue connectors were backwards
4. The 15a fuel pump fuse was also blown
4. Swapped them replaced the fuse and drove 1/2 mile again and it died almost the same spot
5. Luckily my friend had a spare stock fuel pump assembly
6. Installed the stock assembly and replaced the 15a fuse.
7. Drove home about 15 miles away. Car seemed fine.
8. Parked the car. Engine off
9. 10 minutes later, drove down a few blocks and turned off the engine.
10. Started the car and it was stuttering.
11. EcuTek DTC Tool said P0301-00 (Cylinder 1 Misfire Detected) and P0300-00 (Random/Multiple Cylinder Misfire Detected).
12. Cleared the logs and car still stuttered
13. Cleared logs again and now I get P0130-00 (02 Sensor Circuit Bank 1 Sensor 1). Car still stuttered.
13. Cleared logs again and now no errors but car wont start.

What should I check next? Do you think the new pumps are bad?
[/QUOTE
My friend and I installed the AMS LPFP and HPFP.

1. Installed LPFP and HPFP
2. Started the car and drove it about 1/2 mile and the car died sudden
3. Took out the pump and the yellow and blue connectors were backwards
4. The 15a fuel pump fuse was also blown
4. Swapped them replaced the fuse and drove 1/2 mile again and it died almost the same spot
5. Luckily my friend had a spare stock fuel pump assembly
6. Installed the stock assembly and replaced the 15a fuse.
7. Drove home about 15 miles away. Car seemed fine.
8. Parked the car. Engine off
9. 10 minutes later, drove down a few blocks and turned off the engine.
10. Started the car and it was stuttering.
11. EcuTek DTC Tool said P0301-00 (Cylinder 1 Misfire Detected) and P0300-00 (Random/Multiple Cylinder Misfire Detected).
12. Cleared the logs and car still stuttered
13. Cleared logs again and now I get P0130-00 (02 Sensor Circuit Bank 1 Sensor 1). Car still stuttered.
13. Cleared logs again and now no errors but car wont start.

What should I check next? Do you think the new pumps are bad?
Hey blkdrgn I just installed the AMS HPFP and LPFP like your and I’m having the same exact issues. Were you able to figure out the cause of the issue. Please help!
 
#7 ·
You absolutely should get the tune updated after installing an upgraded HPFP.

In AMS' own words:
In order to take full benefits of our HPFP, special Alpha calibrations to your tune will need to be made. Once the HPFP is installed, the vehicle will run. However, tuning may be required and must be checked!
HPFP tuning guide for tuners: https://amsperformance.com/wp-content/uploads/2020/03/RA_HPFP_Tuning_Guide.pdf (this is critical for the tuner to get correctly, as a best-case scenario, a poor tune results in an unreliable car--worst case results in damaged fuel system components.)
 
#11 ·
It was my base map tune that was the issue. Once I got a new map, everything was back to normal.
 
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#12 ·
I’m having the same issue right now and have a stock hpfp and tried the walboro pump and mine was bad so I put the assembly back to stock and put it back in started right up after priming it drove for like 10 minutes then it stalled and wouldn't start after so I pushed it in my driveway and it sat for a day I was out there today and I was listening to see if it was pumping when I turned the ignition on and I heard it and I tried starting it and it started and did the same thing and Let it run for about 10 minutes and it stalled again I’m not tuned I just have a jb4
 
#13 ·
Do you have heavy fuel smell? It could be a stuck injector.
 
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