Injectors not working, power but no ground signal..
#1
Racer
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
So I upgraded my turbo, and got an M-tune.... car has been down for about a month now.... at least....
This project started due to my turbo being worn out so much that it failed State Emissions..... car ran fine before this....
Everything went together fine under the hood fine with bigger turbo install,
M Tune with MAP sensor wiring was very easy... but now I dont have a grounding signal to operate the injectors. Been talking to Joshua(Great product support) and we tried a couple things but still no luck...rechecked wiring(a couple times) and connections and wires....
Car has spark and compression and fuel to the rail. I took out my LR 55lb injectors and reinstalled my old ones, still no luck.... I even reinstalled my OLF LR chip and Vane AFM and still no fuel injector function...
SO long story short( I know not very short) I have dont know what else to check ?????
Anyone got any ideas??
Thanks
Carl
This project started due to my turbo being worn out so much that it failed State Emissions..... car ran fine before this....
Everything went together fine under the hood fine with bigger turbo install,
M Tune with MAP sensor wiring was very easy... but now I dont have a grounding signal to operate the injectors. Been talking to Joshua(Great product support) and we tried a couple things but still no luck...rechecked wiring(a couple times) and connections and wires....
Car has spark and compression and fuel to the rail. I took out my LR 55lb injectors and reinstalled my old ones, still no luck.... I even reinstalled my OLF LR chip and Vane AFM and still no fuel injector function...
SO long story short( I know not very short) I have dont know what else to check ?????
Anyone got any ideas??
Thanks
Carl
#4
Rocket Scientist
Rennlist Member
Rennlist Member
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
You may read voltage at the injector, however, if you do not have enough current, the injectors will not function. What about the DME relay? I would assume Josh has already covered that. If you have power there, though, but not enough current it's likely a harness situation. Connect your multimeter in series and check the amps going through the injector to see how much there is. Obviously if there is zero, grounding issue and I'm wrong.
#6
Burning Brakes
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
did you do any mods to the tach plug under the dash? the wires are also in conjuction to the injector signals. if you did do anything with the wiring there, check there first, otherwise the drivers for the injectors in the dme burned or are bad now.
#7
Racer
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Nope.... I did nothing of the sort...it was R&R turbo, upgrade to LR 55lbs injectors, and M Tune MAF kit....
Trending Topics
#9
Addict
Rennlist Member
Rennlist Small
Business Sponsor
Rennlist Member
Rennlist Small
Business Sponsor
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
If the engine has spark then you can rule out the DME relay and gross DME failure.
You are left with injector driver failure or a wiring issue (as long as you are sure that the injectors are not getting a ground signal from the DME). The injector firing signal at cranking spend is so short that the only thing that will see it is a scope or an injector ‘noid’. Even with a good noid there is not much of a flash.
If you flexed the harness a lot (in the engine area) when you did the install then its quite possible that the wiring has failed – the insulation is very brittle and will crank easily if flexed.
You are left with injector driver failure or a wiring issue (as long as you are sure that the injectors are not getting a ground signal from the DME). The injector firing signal at cranking spend is so short that the only thing that will see it is a scope or an injector ‘noid’. Even with a good noid there is not much of a flash.
If you flexed the harness a lot (in the engine area) when you did the install then its quite possible that the wiring has failed – the insulation is very brittle and will crank easily if flexed.
#12
Racer
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
Well after 2 hours of working on it... I figured it out.... #1 and #2 injector wires were damaged inside the clips....so Im going to order the injector and knock sensor harness from LR..
Thanks for all the help guys!!
Thanks for all the help guys!!
#13
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
I had a similar problem today. I have recently installed the a-tune, 55lb injectors, 3bar, and ballast resistors for the injectors. A few days ago I was inspecting the injector harness with the car running, and when I lifted the harness just a few mm, the engine died. Usually starts back up no problem.
I have also been having an intermittent hard start/ no start problem. I was driving up the street and the car died and would not start, as if it was not getting fuel. I jumpered the fuel pump, and it functioned.
My spare dme relay did not solve the problem either. I checked connections at dme and ballast resistors that had been soldered in, to include the connections for the new MAP sensor. Wiggling something in this area made the difference and I was able to start.
I am thinking that somewhere between floorboard to injector harness, there must be a crack in the wiring since all the soldered joints looked good.
I have also been having an intermittent hard start/ no start problem. I was driving up the street and the car died and would not start, as if it was not getting fuel. I jumpered the fuel pump, and it functioned.
My spare dme relay did not solve the problem either. I checked connections at dme and ballast resistors that had been soldered in, to include the connections for the new MAP sensor. Wiggling something in this area made the difference and I was able to start.
I am thinking that somewhere between floorboard to injector harness, there must be a crack in the wiring since all the soldered joints looked good.
#14
Racer
Thread Starter
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
I had a similar problem today. I have recently installed the a-tune, 55lb injectors, 3bar, and ballast resistors for the injectors. A few days ago I was inspecting the injector harness with the car running, and when I lifted the harness just a few mm, the engine died. Usually starts back up no problem.
I have also been having an intermittent hard start/ no start problem. I was driving up the street and the car died and would not start, as if it was not getting fuel. I jumpered the fuel pump, and it functioned.
My spare dme relay did not solve the problem either. I checked connections at dme and ballast resistors that had been soldered in, to include the connections for the new MAP sensor. Wiggling something in this area made the difference and I was able to start.
I am thinking that somewhere between floorboard to injector harness, there must be a crack in the wiring since all the soldered joints looked good.
I have also been having an intermittent hard start/ no start problem. I was driving up the street and the car died and would not start, as if it was not getting fuel. I jumpered the fuel pump, and it functioned.
My spare dme relay did not solve the problem either. I checked connections at dme and ballast resistors that had been soldered in, to include the connections for the new MAP sensor. Wiggling something in this area made the difference and I was able to start.
I am thinking that somewhere between floorboard to injector harness, there must be a crack in the wiring since all the soldered joints looked good.
Good luck!!
#15
![Default](https://rennlist.com/forums/images/icons/icon1.gif)
cyl 4 was only inj that read 12v on both sides. All other connectors read 12v/10v. All the connectors had some type of corrosion or break in wiring. Found injector connector pigtails from the local auto parts store to solder into the harness.