Dr Tal
Greenie Member
Trying to help a friend get this speed on the road after an engine install alongside mods and base tune. Im getting fuel to the rail but the injectors arent firing and i dont see or smell any fuel in the cylinders. If anyone is an expert that would be able to help with this I would appreciate it as im running out of testable option.
Year/Make/Model: 2012 Mazdapeed 3
Mileage: not sure atm
Location: Moorestown, NJ
Concern:Engine will crank but wont start. Injectors not firing
DTC's:
2006/ p2009/ p430(intake / egr codes)
Modifications: Corksport intake mani with port injection block off plate/ aftermarket exahust mani(not sure which one)/ 3in downpipe./cobb fmic kit/ autotech hpfp internals. Bov, damond engine mounts
ECU/Tuning Software: Not sure what tuner but the basemap that was sent from the tuner.
Tuner:Not sure
Is the concern intermittent? Constant
Can you duplicate the concern? Yes
Recent Repairs: engine was recently refreshed and reinstalled with a reman head with cleaned and flow tested injectors. Ecu replaced with a preprogrammed replacement. Forscan used to reinitlize the modules to get rid of a p1260 immoblizer code that was causing the car to not crank at all.
Correction: Here is everything i have done so far to diagnose the issue:
Checked all grounds: Main battery ground, One on top of hpfp, one on top of trans, two on front of trans, one on passenger side that was relocated becuase of the damond engine mount
Checked Crank position sensor: plugged in and at 20th tooh
Check cam sensor and swapped with known working one
Check to make sure I had spark two different ways. First way using a inline tester(shocked myself on 2 of the 4 coils on the valve cover), Use 2+2 and braklean to try and see if the motor will turn over, It would start briefly until it ran out of gas.
Checked to make sure the fuel rail had pressure multiple ways:
One injector was leaking fuel from a bad top seal that was replaced
Confirmed pressure with AP number 60-90 on koeo with the number jumping to 1700-2000 upon cranking an dropping when the prv bleeds off excess pressure
With ap it looks to be trying to pulse the injectors and the car is saying its supposed to be but idk what the numbers should be considering its not on a stock tune but a basetune map
Replaced the fuel rail+sensor with a spare i had.
Visually inspected the injectors before reinstalling.
Swapped ignition harness with another one as the hpfp connector was broken and causing a p0091 code to appear. (no start with either harness)
Swapped injector harness witha a known working one.
Checked every fuse in both fuse boxes
Swapped inj relay with one from a different car
Used a borescope to check inside each cylinder to see if there was any fuel or anything else and there wasnt.
cant compression test it as the numbers will be inconsistant until the rings are fully seated.
The only things I havent tried is:
replacing the ecu agn or trying to program another one (possible as the ecm isnt the original with the car, it was lost by previous owner so another was purchsed with vin preprogrammed in.)
Swapping to another set of injectors (i doubt all 4 would go bad at once)
I havent checked to make sure that i have continuity for each injector connection back to ecm (the chances all 4 injectors would have harness issues and nothing else seems to be is highly unlikely)
I dont have a noid light to test but will pick up a kit and a fuel injector test kit soon.
I plan on testing to see if with the rail pressurized if i can get the injectors to fire using a test kit. If i can i know its most likely ecu related.
Few other things of note. The car was sitting for a while with engine installed before it was attempted to be started. ( engine got put in late last year, It only recently got around to be started.) I did make sure the engine could turn over by hand before filling it with fluids. Also i put a small amount of oil in each cylinder to try and lube the walls a bit to make sure the rings didnt get stuck and cause issues.
Year/Make/Model: 2012 Mazdapeed 3
Mileage: not sure atm
Location: Moorestown, NJ
Concern:Engine will crank but wont start. Injectors not firing
DTC's:
2006/ p2009/ p430(intake / egr codes)Modifications: Corksport intake mani with port injection block off plate/ aftermarket exahust mani(not sure which one)/ 3in downpipe./cobb fmic kit/ autotech hpfp internals. Bov, damond engine mounts
ECU/Tuning Software: Not sure what tuner but the basemap that was sent from the tuner.
Tuner:Not sure
Is the concern intermittent? Constant
Can you duplicate the concern? Yes
Recent Repairs: engine was recently refreshed and reinstalled with a reman head with cleaned and flow tested injectors. Ecu replaced with a preprogrammed replacement. Forscan used to reinitlize the modules to get rid of a p1260 immoblizer code that was causing the car to not crank at all.
Correction: Here is everything i have done so far to diagnose the issue:
Checked all grounds: Main battery ground, One on top of hpfp, one on top of trans, two on front of trans, one on passenger side that was relocated becuase of the damond engine mount
Checked Crank position sensor: plugged in and at 20th tooh
Check cam sensor and swapped with known working one
Check to make sure I had spark two different ways. First way using a inline tester(shocked myself on 2 of the 4 coils on the valve cover), Use 2+2 and braklean to try and see if the motor will turn over, It would start briefly until it ran out of gas.
Checked to make sure the fuel rail had pressure multiple ways:
One injector was leaking fuel from a bad top seal that was replaced
Confirmed pressure with AP number 60-90 on koeo with the number jumping to 1700-2000 upon cranking an dropping when the prv bleeds off excess pressure
With ap it looks to be trying to pulse the injectors and the car is saying its supposed to be but idk what the numbers should be considering its not on a stock tune but a basetune map
Replaced the fuel rail+sensor with a spare i had.
Visually inspected the injectors before reinstalling.
Swapped ignition harness with another one as the hpfp connector was broken and causing a p0091 code to appear. (no start with either harness)
Swapped injector harness witha a known working one.
Checked every fuse in both fuse boxes
Swapped inj relay with one from a different car
Used a borescope to check inside each cylinder to see if there was any fuel or anything else and there wasnt.
cant compression test it as the numbers will be inconsistant until the rings are fully seated.
The only things I havent tried is:
replacing the ecu agn or trying to program another one (possible as the ecm isnt the original with the car, it was lost by previous owner so another was purchsed with vin preprogrammed in.)
Swapping to another set of injectors (i doubt all 4 would go bad at once)
I havent checked to make sure that i have continuity for each injector connection back to ecm (the chances all 4 injectors would have harness issues and nothing else seems to be is highly unlikely)
I dont have a noid light to test but will pick up a kit and a fuel injector test kit soon.
I plan on testing to see if with the rail pressurized if i can get the injectors to fire using a test kit. If i can i know its most likely ecu related.
Few other things of note. The car was sitting for a while with engine installed before it was attempted to be started. ( engine got put in late last year, It only recently got around to be started.) I did make sure the engine could turn over by hand before filling it with fluids. Also i put a small amount of oil in each cylinder to try and lube the walls a bit to make sure the rings didnt get stuck and cause issues.
