eke_zetec_RWD Posted January 23, 2007 Share Posted January 23, 2007 so what has changed since it went 2weeks ago. you say you have new plugs..... did you change these in the last 2 weeks? if so check your firing order ect..has it been tuned? are you running sierra dizzy? check for power at injectors and coil. most after market computers will turn off below a set voltage ( say 8V ) so measure volts at the computer while cranking. Quote Link to comment Share on other sites More sharing options...
nismo.capri Posted January 23, 2007 Share Posted January 23, 2007 so what has changed since it went 2weeks ago. Good call! I've always found that 99% of the time even if what I was doing wasn't related it usually turns out that it is, bumped something etc. This is true of cars and computers. you say you have new plugs..... did you change these in the last 2 weeks? if so check your firing order ect..has it been tuned? are you running sierra dizzy? check for power at injectors and coil. Yup gizzy_esky needs to confirm what's going and what's not. With the Link it only powers the fuel pump, injectors and coil once it's getting a dizzy signal. Does anyone know if the injec EM1 does this? most after market computers will turn off below a set voltage ( say 8V ) so measure volts at the computer while cranking. Jump starting would have started it if that was the case. Quote Link to comment Share on other sites More sharing options...
lowlancer Posted January 23, 2007 Share Posted January 23, 2007 Microtech will still power pumps without dizzy signal, but not injectors and certainly not coil, as it needs signal from dizzy to know when to fire. Quote Link to comment Share on other sites More sharing options...
Guest gizzy_esky Posted January 23, 2007 Share Posted January 23, 2007 thanks for the advice, plugs havnt changed since it was last going...infact nothing has as far as im aware...i will check voltage at computer thats a good point....im thinking the wire from coil to computer is damaged or somthing, as when i checked the current going to the injectors it was only weak...ie light on tester was dim...it would be good to get it running before the shop looks at it, that way i dont have to hire a trailer to get it there.. Quote Link to comment Share on other sites More sharing options...
Guest gizzy_esky Posted January 23, 2007 Share Posted January 23, 2007 oh and re the question about the injec EM1...it only controlls the fuel side of things, it doesnt controll the coil etc... Quote Link to comment Share on other sites More sharing options...
Guest gizzy_esky Posted January 23, 2007 Share Posted January 23, 2007 running cortina dizzy car has been tuned while it was running last there is spark...so i think it's a fuel problem....i don't think injectors are getting ENOUGH current to fire??? is this possible and does anyone know how this could happen?? i am lead to believe this as they are only getting a weak current from the computor....could the relay that supplies the injectors be to blame? Quote Link to comment Share on other sites More sharing options...
Raizer Posted January 23, 2007 Share Posted January 23, 2007 Test what voltage your getting at the injectors with a multimeter, should be around 11v min, the ecu should only supply a neg- pulse to fire the injectors Quote Link to comment Share on other sites More sharing options...
lowlancer Posted January 23, 2007 Share Posted January 23, 2007 running cortina dizzycar has been tuned while it was running last there is spark...so i think it's a fuel problem....i don't think injectors are getting ENOUGH current to fire??? is this possible and does anyone know how this could happen?? i am lead to believe this as they are only getting a weak current from the computor....could the relay that supplies the injectors be to blame? Unplug your fuel pump, switch key to RUN, then turn dizzy shaft to hear if injectors are clicking Quote Link to comment Share on other sites More sharing options...
nismo.capri Posted January 23, 2007 Share Posted January 23, 2007 Microtech will still power pumps without dizzy signal, but not injectors and certainly not coil, as it needs signal from dizzy to know when to fire. Sorry I didn't explaine that well.... the link drives a relay that supplies 12v to the fuel pump, injectors and coil. The link like most ECU's switches the -ve to fire the injectors and coil (This is becuse they use MOSFETS for their current humping ability) When the key is turned to on the link fires up the 12v, you can hear the pump run for 3 secs then switches off as the link turns the relay off. When the key is turned to start the engine starts cranking and the dizzy starts pulsing the Link now knows the car is being cranked and it fires the relay that supplies the fuel pump, injectors and coil and the engine starts. The reason for doing this is saftey and to stop the coil getting cooked if the key gets left in the on position. As you'd see with a Link you can have a fueling and spark problem that is actually a dizzy issue. Quote Link to comment Share on other sites More sharing options...
nismo.capri Posted January 23, 2007 Share Posted January 23, 2007 running cortina dizzyis spark...so i think it's a fuel problem....i don't think injectors are getting ENOUGH current to fire??? is this possible and does anyone know how this could happen?? Yes it's completely possible. You probably have a bung connection somewhere like the crimp connection to the injector power feed for example. i am lead to believe this as they are only getting a weak current from the computor....could the relay that supplies the injectors be to blame? Do you have a multi or amp meter that will handle 6-8 amps? If you do put it in series with the injector power feed and see what it reads when cranking. What injectors are you running do your know their resistance? Are they wired in parallel or series? Are you running a ballast resistor? Do you know if you are runing the right resistance injectors for the ECU? I'm runing peak/hold injectors with my Link and it's designed for saturated injectors so I have to run a ballast resistor to limit the current to the injectors. Quote Link to comment Share on other sites More sharing options...
Guest gizzy_esky Posted January 24, 2007 Share Posted January 24, 2007 just tested the injector -ve and +ve feeds and what i found was that the injectors are getting a constant -ve feed even when the engine ISNT cranking....ie key ON not START....+ve also has constant voltage..im sure that like you say the injectors should only get a -ve feed when the engine is cranking....do you have any idea why this could be?? ive checked all joins/connections in wiring to injectors and relay and they are all soldered and wrapped properly...could the constant -ve feed be because the computor is recieving a constant (not pulse) feed from the coil? if so what could be wring?? thanks for the help so far...we're sstarting to suss this out bit by bit! Quote Link to comment Share on other sites More sharing options...
nismo.capri Posted January 24, 2007 Share Posted January 24, 2007 just tested the injector -ve and +ve feeds and what i found was that the injectors are getting a constant -ve feed even when the engine ISNT cranking....ie key ON not START....+ve also has constant voltage..im sure that like you say the injectors should only get a -ve feed when the engine is cranking....do you have any idea why this could be?? how did you check the -ve? In circuit or unpluged? If the injector is in circuit it should be battery voltage or a bit lower. get some one to crank the car over and the voltage should pulse up and down Quote Link to comment Share on other sites More sharing options...
Guest gizzy_esky Posted January 24, 2007 Share Posted January 24, 2007 i checked it in circuit...it was full battery voltage, i will double check the pulsing while cranking tonight after work...... Quote Link to comment Share on other sites More sharing options...
eke_zetec_RWD Posted January 25, 2007 Share Posted January 25, 2007 pull the plug off an all the injectors not just one when u test them as it can back feed through the others. there shud be around 12V on one terminal, now with multi meter on ohms test the other wire to see it is dead shorting to the pinout on the computer, it should be. but it shouldnt be dead shorting to earth. if it is uplug the computer and check if its shorting through the ecu or in the lume itself. be sure to use a multi meter and not a test light as putting staight 12V into the ecu could damage drivers ect. beter safe than sorry. have you tested fuel pressure? should be atlest 30psi. gud luck, how did it go on the dyno? Quote Link to comment Share on other sites More sharing options...
nismo.capri Posted January 26, 2007 Share Posted January 26, 2007 this is how your injectors are wired right? With the key in the on position, all injectors connected and the -ve lead of the multi meter going to the body or battery -ve you should have battery voltage say 12v at point A and point B. Crank it and you should have ~12v at point A and it should pulse between ~12v and ~0v as the ecu earths the injector causing a current flow and voltage drop across the injector(s). The dirty dog way to test the injectors is get some one to crank it while you manually earth out the ecu side of the injectors causing them to fire, don't hold it on the -ve just pulse them. If it fires even just a little pop you'll know that the injectors and wiring arn't the problem but they also aren't getting fired by the ECU. Then you need to check if the ecu is getting a trigger signal.... I'm guessing that it gets this from teh -ve of the coil? Quote Link to comment Share on other sites More sharing options...
Guest gizzy_esky Posted January 30, 2007 Share Posted January 30, 2007 thanks for that, i will do what you just described tonight hopefully....just got back from masterton drags sorry for the late reply! drags were awesome...might throw up a couple pics of the mk1 escort that entered in the burnouts tonight...oh and the 10sec mk1 drag car! Quote Link to comment Share on other sites More sharing options...
Guest gizzy_esky Posted January 30, 2007 Share Posted January 30, 2007 With the key in the on position, all injectors connected and the -ve lead of the multi meter going to the body or battery -ve you should have battery voltage say 12v at point A and point B. Thats all good, everything is as described Crank it and you should have ~12v at point A and it should pulse between ~12v and ~0v as the ecu earths the injector causing a current flow and voltage drop across the injector(s). It doesnt pulse at all, just a small drop in voltage from 12 to about 11 due to cranking over i suppose The dirty dog way to test the injectors is get some one to crank it while you manually earth out the ecu side of the injectors causing them to fire, don't hold it on the -ve just pulse them. Did this and it still didnt pop or fire or anything...sprayed some engine start in it to check spark and it popped so spark isnt a problem... Perhaps injector plugs are Stuffed? according to retrotech website its a possibility?? Quote Link to comment Share on other sites More sharing options...
Guest gizzy_esky Posted January 30, 2007 Share Posted January 30, 2007 BUY new injector plugs! We wasted heaps of time fluffy round with injector hassles trying to use the old plugs. Even though they looked ok and connected there's no room for leeway with the injector plug wire. It has to be perfect, so save yourself time and fork out for brand new plugs. I brought Bosch ones from LINK that were $20 each! But probably the best improvement expenditure of the whole system. http://www.retrotech.co.nz/pinto.html Quote Link to comment Share on other sites More sharing options...
nismo.capri Posted January 30, 2007 Share Posted January 30, 2007 It doesnt pulse at all, just a small drop in voltage from 12 to about 11 due to cranking over i suppose Yep voltage will drop a bit on cranking.... The injectors aren't firing so it's suffering from no fuel.... Now you need to find out why they aren't... Did this and it still didnt pop or fire or anything... Bugger..... sprayed some engine start in it to check spark and it popped so spark isnt a problem... Sweet that confirms that it's a fuel issue. Perhaps injector plugs are Stuffed? according to retrotech website its a possibility?? Yep but I'd have expected at least a pop from 1 or 2 pots, I'd be surprised if they were all bung. There are 3 possibilities I can think of... 1)ECU isn't getting a trigger signal. 2)The output FET in the ECU that drives the injectors has blown. 3) Wireing issues, including injector plugs. Measure the resistance across the injector loom, if you look at the diag above measure between +12 and ECU points, they must be disconnected. It should read between 2-4 ohms. It would also pay to run these wires to the battery, hold the ecu wire on the -ve then tap the injector +ve to the +ve of the battery, you should hear the injecotrs click each time you tap the +ve. Don't hold it on as you could fry the injectors. You need to check the ECU Earth if it's not earthed well it can't hump the current to fire the injectors. Run another temp ëarth to the ECU earth just to be sure. You need to check the ECU trigger. Are you running a ballest resistors on the injectors? Does it trigger off the coil -ve? Quote Link to comment Share on other sites More sharing options...
Guest gizzy_esky Posted January 30, 2007 Share Posted January 30, 2007 kewl thanks for that will try all that tonight...no it doesnt have a ballast resistor...and yes it triggers off coil -ve Quote Link to comment Share on other sites More sharing options...
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