Kevin.pk Posted June 21, 2005 Share Posted June 21, 2005 Alright i have done plenty of searching and cant find anyhitng that pertains to my question. Alright when i first tried starting the motor i got spark... it was consistent .. then shortly after i got my fuel pump wired spark just stopped... i checked the signal wire to the ignitor with a test light and it is not pulsing or anyhting... so assuming the ECU went.... i got another computer hooked it up and still no spark... Everything is wired correctly ... i have checked it numerous times... i just dont get it..... could it be somehitng as simple as a bad ground... nothing has changed since it was orginally getting spark.... any help is appreciated... thanks Kevin Quote Link to comment Share on other sites More sharing options...
PeterZ Posted June 21, 2005 Share Posted June 21, 2005 Someone else here reminded us that the ignition switch can wear and lose ignition when the key is turned too far. If this is the problem you can turn the key back a little when cranking and all will be well. Quote Link to comment Share on other sites More sharing options...
Kevin.pk Posted June 22, 2005 Author Share Posted June 22, 2005 well i tried messing with the ignition switch and still no spark... i checked and cleaned all my grounds and still nothing.... anyone else with suggestions... im completely stumped... all help is appreciated Kevin Quote Link to comment Share on other sites More sharing options...
EZ-E Posted June 22, 2005 Share Posted June 22, 2005 I know this sounds silly but I did this once while cleaning all connections and redoing the grounds and such, the connection that goes to the distributor, via the trail that the injector harness takes, looked connected, yet it wasnt, ie no spark. Make sure it is connected. Just a guess and something that happened to me hopefully it is that simple. Good luck! Quote Link to comment Share on other sites More sharing options...
PeterZ Posted June 22, 2005 Share Posted June 22, 2005 I recommend check basics-(Fuel, compression and spark at the right time) You didn't change anything for compression so: Verify fuel pressure. An ECU means fuel injected car 35-45 PSI fuel pressure. + side of coil should be batt voltage during cranking, neg side of coil should pulse (with a test light). If no batt voltage at coil pos. there is probably an interesting elecdtrical problem. If there's no pulse at coil neg (but coil + is OK) there's most likely a dist problem. You worked on the fuel pump electrical, Check associated electrics in that area too. Where are you checking for spark and how are you checking? Quote Link to comment Share on other sites More sharing options...
Kevin.pk Posted June 22, 2005 Author Share Posted June 22, 2005 im checking spark before it even gets to the coil... the coil is brand new so that is not the problem... the problem is that im not getting a signal on the Y/W wire from the ecu to the ignitor to make the coil fire... its supposedly suppose to pulse while cranking. i've tried two computers now.... the first one worked orignally and then next thing i knew spark stopped for no apparent reason... so i thought maybe my ECU went out so i put in a different one and still no luck.... ive actually got another one coming that i bought off ebay.... maybe i just had two bad ecus.... is there anythign specail that needs to be done to an Automatic transmission ECU when used on a manual car? cause i only have autmatic ECUs but have one for a manual on the way And ill have to double check the connection to the distributor wheni get home. im still hoping its somehting simple that im just overlooking Kevin Quote Link to comment Share on other sites More sharing options...
EZ-E Posted June 22, 2005 Share Posted June 22, 2005 Is the ignitor properly grounded? When mounting my new coil I had broken it off from the coil bracket and it does need a good ground or it will not function. Just something else to check. Quote Link to comment Share on other sites More sharing options...
Afshin Posted June 22, 2005 Share Posted June 22, 2005 How are you checking for the pulsed signal from the ecu to the ignitor? A voltmeter will usually not pick up a short ignition pulse and will read no signal when there is indeed one. If your voltmeter has a duty cycle function or if you have an oscilloscope.. then you can check for the pulse (it's hardly ever the ecu). Quote Link to comment Share on other sites More sharing options...
Afshin Posted June 22, 2005 Share Posted June 22, 2005 ANother thing just came to mind, I'm not sure of this, but it may also be that the signal will be too weak to pick up from the ecu if there is no signal drain from the ignitor. For example with the SDS system which uses he MSD box as the signal amplification module, the voltmeter/autometer duty signal funtion will not read a pulse unless the ingition pulse wire fron the SDS ecu is actually connected to the msd box. In other words it may be that checking the signal straight from the ecu without the ignition circuit being complete (ignitor functioning and connected...) may have too weak a signal for even the duty cycle function on autometers to pick it up. Quote Link to comment Share on other sites More sharing options...
VinhZXT Posted June 23, 2005 Share Posted June 23, 2005 Listen to EZ-E.. Check the connection for the CAS. That's the signal that the ECU will use to give you sparks. Try to put in another turbo distributor. Quote Link to comment Share on other sites More sharing options...
Kevin.pk Posted June 23, 2005 Author Share Posted June 23, 2005 well im getting 12 volts on the negative and positive side of the coil and im getting 12 volts at the coil wire to the distributor. alright well i tried cleaning the contacts at the CAS connector but still no luck.... the negative side of the coil isnt pulsing while cranking so im assuming the CAS is messed up so i guees its time for a new distributor.. Anyone have an extra turbo distributor they are willing to sell? Kevin Quote Link to comment Share on other sites More sharing options...
Afshin Posted June 24, 2005 Share Posted June 24, 2005 I just sent you a PM. Quote Link to comment Share on other sites More sharing options...
getZ Posted June 25, 2005 Share Posted June 25, 2005 How did you wire the fuel pump? The output of the ecu for the fuel pump will not drive the pump. It has to be hooked up to a relay. Computer outputs do not put out enough current to drive such large devices. The ignitor is a power transistor and in the case of the z car used like a relay. The voltage at the base (ignitor input) has to always be on for the coil to have power. In reality the power is always connected and the output signal from the ecu connects the negative end of the coil to ground. It also should not take much of a voltage to drive the ignitor to switch the coil on. I can see my ignitor go on but it is only something like 2 volts. It probably only need .7 volts to work. By the way the ignitor signal does look like a pulse because it is not a steady output. When first switched on the voltage is about 3 volts and then drops down, but it cannot go to zero or the coil will not work. Quote Link to comment Share on other sites More sharing options...
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