engine swap done.... secondarys not firing :/
#1
engine swap done.... secondarys not firing :/
hey guys!
So, my engine swapt (1987 Turbo with a "new" used 1987 TurboII engine) is finally finished
the engine runs soooooooooooo sweet smooth at IDLE, everythin works...
the car pulls fine in the low RPM's, the turbo is spooling up like on LSD or XTC...
the complete engine harness had been rebuilded, every cable is in perfect condition...
but we have a problem... the engine is fine up to 3,8k rpm, then it feels like i hit a wall and i have a little backfire... so my secondarys are'nt fireing right!?
so, what could cause this?
tommorow i will swap my "old" secondarys from the old engine into the new...
what are the reasons for not firing the secondarys?
bad injectors
bad harness (impossible)
bad ECU (it's the same ecu like it was before... should be fine)
...
???
pls help me out... the car must run tommorow
So, my engine swapt (1987 Turbo with a "new" used 1987 TurboII engine) is finally finished
the engine runs soooooooooooo sweet smooth at IDLE, everythin works...
the car pulls fine in the low RPM's, the turbo is spooling up like on LSD or XTC...
the complete engine harness had been rebuilded, every cable is in perfect condition...
but we have a problem... the engine is fine up to 3,8k rpm, then it feels like i hit a wall and i have a little backfire... so my secondarys are'nt fireing right!?
so, what could cause this?
tommorow i will swap my "old" secondarys from the old engine into the new...
what are the reasons for not firing the secondarys?
bad injectors
bad harness (impossible)
bad ECU (it's the same ecu like it was before... should be fine)
...
???
pls help me out... the car must run tommorow
#6
HAILERS
Join Date: May 2001
Location: FORT WORTH, TEXAS,USA
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You could get a meter and back probe one of the Secondary injector wires at the ECU. Below 3500rpm the reading will be whatever the voltage the alternator is putting out. Once you cross 3500rpm AND have your foot in it, the voltage should drop dramatically. Say from 12vdc down to 7vdc or even as low as five.
If the voltage does as above, the injectors are firing. If it remains the same, the ECU isn't pulsating a ground to the injector.
You can do the same in your dirveway if you want. BUT you have to pull the vacuum line off the boost sensor and plug the line. Now everytime you reach 3500rpm the voltage will drop on the secondary injectors WHETHER OR NOT you have your foot in it. Even gentley acceleration above 3500rpm will trigger the secondary's to come online. BUT the voltage drop will NOT be as dramatic as describe above with everything connected i.e. vacuum hose to boost sensor.
If the voltage does as above, the injectors are firing. If it remains the same, the ECU isn't pulsating a ground to the injector.
You can do the same in your dirveway if you want. BUT you have to pull the vacuum line off the boost sensor and plug the line. Now everytime you reach 3500rpm the voltage will drop on the secondary injectors WHETHER OR NOT you have your foot in it. Even gentley acceleration above 3500rpm will trigger the secondary's to come online. BUT the voltage drop will NOT be as dramatic as describe above with everything connected i.e. vacuum hose to boost sensor.
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#8
I'm a boost creep...
Join Date: Jan 2002
Location: Auckland, New Zealand
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Originally Posted by hondahater
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A problem like this usually means a secondary injector plug has been left loose or fallen off or a secondary injector is dead, which proved to be the case.
Last edited by NZConvertible; 04-29-06 at 05:51 PM.
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