Anyone else have problems with Percision 780 injectors?
11-19-2005, 11:21 AM
#1
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Anyone else have problems with Percision 780 injectors?
I had my car tuned the other day and when he put the basemap for 780 injectors the car was ungodly lean. so then we put a 450 basemap on and it ran fine. The injectors are brand new Percision 780's and i verafied with Percision that they are the correct ones with the partnumber stamped on them. I am runnign these on a boosted h22a in a 90 accord so there is a resistor box. I am running Crome but the same thing happens with Uberdata. Even though they are brand new they wont refund my money so im stuck with them. Anyone have any ideas? 
11-19-2005, 08:24 PM
#5
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Re: Anyone else have problems with Percision 780 injectors?
Like he said whats your fuel pressure? If its too low then it will run lean on a standard basemap made for that size injector. Its called a basemap for a reason. With big injectors like that a basemap is never anywhere close to having the right amount of fuel. Get it tuned.
11-20-2005, 07:47 PM
#7
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Re: Anyone else have problems with Percision 780 injectors?
Originally Posted by sohc_mshue
Like he said whats your fuel pressure? If its too low then it will run lean on a standard basemap made for that size injector. Its called a basemap for a reason. With big injectors like that a basemap is never anywhere close to having the right amount of fuel. Get it tuned.
A. they wont exchange them.
B. they ARE 780's ( i read them the part numbers to verafy)
C. i was having it tuned and the tuner said he has had problems with Percision 780's before and he just put RC 750's in and it totaly cured the problem.
D. it is a stock fuel pump of a 90 accord(i know its to small BUT 1 problem at a time.) See what happened is with the 780 base map the idle fuel value was at a genaric starting point of lets say 17 but at idle it was SO lean that he had to put the values to 230 or more.but once the values were at the 230ish it idled fine. if it there was not enough fuel pressure it wouldnt richen up by raising the values. and with a 450 fuel map the values set at the genaric 17 idled it fine.. Im lost and dont know what to do.
11-20-2005, 11:01 PM
#8
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Re: Anyone else have problems with Percision 780 injectors?
larger inj have more mass to them and require more pulse at idle than you'd think. every large inj car i've tuned needed more than i thought to idle well. just tune it...heep adding fuel at idle, and then continue to tune as normal.
11-21-2005, 07:18 AM
#9
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Re: Anyone else have problems with Percision 780 injectors?
i know the guy that 'attempted' to tune this car, he is more than competant enough and has tuned a few 1000cc injectors cars that i know of with no problems. the problem doesn't lay in the tune or tuner, but i'm pretty sure it's the injector's. i've had problems with other injectors as well (delphi, siemens/deka, venom, etc.). the only injectors i have never had a problem with and set of, are rc's and dsm's. get some new injectors jeff, quit trying to polish a turd 
11-21-2005, 05:40 PM
#10
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Re: Anyone else have problems with Percision 780 injectors?
Originally Posted by projekteg
i know the guy that 'attempted' to tune this car, he is more than competant enough and has tuned a few 1000cc injectors cars that i know of with no problems. the problem doesn't lay in the tune or tuner, but i'm pretty sure it's the injector's. i've had problems with other injectors as well (delphi, siemens/deka, venom, etc.). the only injectors i have never had a problem with and set of, are rc's and dsm's. get some new injectors jeff, quit trying to polish a turd
