Trouble shooting the Fuel Injection, Checking the volts and resistance on a D-Jet 1.7 '70 |
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Trouble shooting the Fuel Injection, Checking the volts and resistance on a D-Jet 1.7 '70 |
tabs914 |
Oct 16 2009, 01:58 PM
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#1
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Advertise Your Drive... Group: Members Posts: 105 Joined: 17-January 05 From: Gresham, Oregon Member No.: 3,456 Region Association: None |
Hello all... I have been trying to trouble shoot my non-starting 914(just cranks). I figured I would start on the fuel injection system, making sure the ECU is getting the proper signals. Here is what I have checked:
MPS Vacuum: Holds 5 Min. + Main Coil: 56 ohms SPEC: 90 Secondary Coil: 348 ohms SPEC: 350 Injectors: SPEC 3 ohms for all injectors Inj 1: 3 ohms Inj 2: 3 ohms Inj 3: 2 ohms Inj 4: 2 ohms Throttle Position Switch Idle Contact: Spec .5 ohms .68 ohms Head Temp Sensor: SPEC 2k ohms Also it is new... 3k ohms I cleaned the trigger points (I don't know if it was a fluke, but this sparked a stummble for one second, only once) New cap/rotor/points Checked Spark from coil wire (Good) Checked Spark from cap (good) Checked Spark at plug (good) Fuel Pump Primes when key is turned Checked the injectors for pulse (when cranking) Good. New fuel filter and lines (the pump is installed correctly I have checked several times (IMG:style_emoticons/default/smile.gif) The AAR warms up if connected to 12 volt. warm closes and opens when cooled down. (not sure if it should do this if I just turn the ignition on? - doesnt seem to warm up if I do.) New vacuum lines backed up with clamps on all connections I can't check fuel pressure - I don't have a guage nor for compression either. Anyone in Portland, Oregon or Vancouver, Washington I can borrow from? (IMG:style_emoticons/default/smile.gif) Maybe someone in the area that can help me out, would be very cool. I am learning alot, but this has me stumped. I haven't had her on the road yet, but I had this baby running pretty well. I was messing around with the head temp sensor when it died. I thought maybe the wire lead became damaged within the sensor casing? Bought a new sensor with no effect. I have three ECU's and I know two work (no effect) The triggers seemed to sparked a stumble, they look ok... any way to test them? Thank you for your help. (IMG:style_emoticons/default/biggrin.gif) Tab |
type47 |
Oct 16 2009, 03:15 PM
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#2
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Viermeister Group: Members Posts: 4,254 Joined: 7-August 03 From: Vienna, VA Member No.: 994 Region Association: MidAtlantic Region |
Trigger points are just basically on-off switches, little to no adjustment. You can make a fuel pressure gauge with a gauge from the plumbing dept of Home Depot or Lowes or whatever your hardware store is. Get the barbed fitting and whateverelse is needed to screw the gauge into and a piece of FI hose and you're good. But, if it was running good before, I doubt the pressure changed. Definately need the head temp sensor to start though, needs to be ~3k ohms cold decreasing to low resistance (single digit ohms?) when hot
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tabs914 |
Oct 16 2009, 03:24 PM
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#3
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Advertise Your Drive... Group: Members Posts: 105 Joined: 17-January 05 From: Gresham, Oregon Member No.: 3,456 Region Association: None |
Trigger points are just basically on-off switches, little to no adjustment. You can make a fuel pressure gauge with a gauge from the plumbing dept of Home Depot or Lowes or whatever your hardware store is. Get the barbed fitting and whateverelse is needed to screw the gauge into and a piece of FI hose and you're good. But, if it was running good before, I doubt the pressure changed. Definately need the head temp sensor to start though, needs to be ~3k ohms cold decreasing to low resistance (single digit ohms?) when hot 3k at the sensor or at the ECU? Thanks (IMG:style_emoticons/default/biggrin.gif) |
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