91 iX no start, but not throwing any codes

[johnt325ix]

Correction. Meant to say fuel pump and fuel pump relay.

[zcenterb]

timings fine as far as i can tell, cam is spinning as it should, but how do i check if the distributer is in the right position? i replaced the rotor and cap and it seemed to be fine. And yes I'm getting fuel, i got sprayed in the face twice to prove it....

[zcenterb]

Relays fine also, bench tested it multiple times and it worked as it should.

[zcenterb]

It seems to be just spark that I'm not getting, although i haven't gotten a chance to check and see if I'm getting injector pulse yet

[spdracrm3]

Timing? Check if distributer is in wrong position.

if there is no spark out of the coil ,where the distributor is will not make any difference as there isnt even any spark getting to it . nothing in the distributor controls/influences spark creation at coil...only where it goes after the coil has created it

"So I'm not getting any power out of my coil to ignite my plugs."

you mean spark ? or are you trying to measure voltage out of the coil tower terminal (which you cant do with a DVOM you need a scope to acutually measure spark output/pattern)



" I am getting 12v on both of the wires going to the coil though...."

(this is normal as your seeing the voltage from the ignition switch at coil + terminal going thru the windings of the coil primary out the coil - (neg) terminal and it can be measured back at the ECU also at pin 1 if the circuit is good (the ECU grounds this voltage allowing current flow ,it then opens the circuit when it wants a spark buy opening the circuit this causes a field collapse and induces a high voltage in the secondary windings that you see as a spark out of the coil tower terminal ) which is then Distributed by the distributor to the correct sparkplug wire and sparkplug igniting the fuel to make power and move you down the road.....this control can be tested at the coil with a test light as it will flash as ECU switches coil neg terminal

OP did you test for a control signal at the coil -(neg) terminal with a test light? if not flashing test back at ECU for voltage thru the circuit back to pin 1 of ECU key on and also for a flashing signal testing with a test light while cranking to test the control circuit integrity.....if everything there checks out your not getting the signals the ECU needs to send a control signal to coil or the ECU has a problem

[zcenterb]

if there is no spark out of the coil ,where the distributor is will not make any difference as there isnt even any spark getting to it . nothing in the distributor controls/influences spark creation at coil...only where it goes after the coil has created it

I understand that.

"So I'm not getting any power out of my coil to ignite my plugs."

you mean spark ? or are you trying to measure voltage out of the coil tower terminal (which you cant do with a DVOM you need a scope to acutually measure spark output/pattern)

Yes spark plugs... and i did run a test light the the coil and wasn't getting anything out of the "coil tower terminal" as you called it, the one that send the power surge to the distributer to be distributed. To double check i tried it on a running e30 and got a very consistent blinking and very bright light... I.E. it was working...

" I am getting 12v on both of the wires going to the coil though...."

(this is normal as your seeing the voltage from the ignition switch at coil + terminal going thru the windings of the coil primary out the coil - (neg) terminal and it can be measured back at the ECU also at pin 1 if the circuit is good (the ECU grounds this voltage allowing current flow ,it then opens the circuit when it wants a spark buy opening the circuit this causes a field collapse and induces a high voltage in the secondary windings that you see as a spark out of the coil tower terminal ) which is then Distributed by the distributor to the correct sparkplug wire and sparkplug igniting the fuel to make power and move you down the road.....this control can be tested at the coil with a test light as it will flash as ECU switches coil neg terminal

No flashing light. Although as far as my understanding goes, i should have 12v on both the + and - terminals (not the tower terminal) correct? At that point its up the the DME to make or break the circuit to cause the spark, yes? Because at this point i have replaced everything the DME needs to ignite the car, including crank sensor, cylinder sensor, etc.

OP did you test for a control signal at the coil -(neg) terminal with a test light? if not flashing test back at ECU for voltage thru the circuit back to pin 1 of ECU key on and also for a flashing signal testing with a test light while cranking to test the control circuit integrity.....if everything there checks out your not getting the signals the ECU needs to send a control signal to coil or the ECU has a problem

Again, i have replaced all the sensor as far as i know that the DME needs to fire the engine (create spark). I have also replaced every single aspect of spark from the spark plugs all the way back to the coil with proven working parts. Im just not getting that surge out of the tower terminal. I have a new unopened DME coming in the mail, hopefully that'll do it. Ill see if i can light test the DME today and try your test on the - terminal, but with the key on run i know its getting constant power, which i believe is supposed to happen until the DME makes or breaks the circuit.

Just out of curiosity would just a simple lack of battery power make the engine not spark? the voltage meter reads like 11.5v on the + and - of the coil but ~12.3v between the battery terminals. Odd? Problem? Parasitic drain somewhere? Thanks for the help

[spdracrm3]

"No flashing light NOT GOOD. Although as far as my understanding goes, i should have 12v on both the + and - terminals (not the tower terminal) correct?" YES


At that point its up the the DME to make or break the circuit to cause the spark, yes?RIGHT

Because at this point i have replaced everything the DME needs to ignite the car, including crank sensor, cylinder sensor, etc." now you need to test circuit integrity back to ECU and pinout all the other pins at ECU for correct powers,grounds and signals (you will need a scope to test crank sensor signal at ECU) . something is causing no signal to get to coil from ECU either the wiring to coil from ECU or another sensor or a bad ECU ,a missing voltage or ground , you may be at the end of your testing capabilities and need to have a shop test it ?

Again, i have replaced all the sensor as far as i know that the DME needs to fire the engine (create spark). I have also replaced every single aspect of spark from the spark plugs all the way back to the coil with proven working parts. Im just not getting that surge out of the tower terminal. I have a new unopened DME coming in the mail, hopefully that'll do it. Ill see if i can light test the DME today and try your test on the - terminal, but with the key on run i know its getting constant power, which i believe is supposed to happen until the DME makes or breaks the circuit.RIGHT (this will be seen as a test light flashing if the system was working correctly) ,thought you already tried a working DME/ECU?

Just out of curiosity would just a simple lack of battery power make the engine not spark? the voltage meter reads like 11.5v on the + and - of the coil but ~12.3v between the battery terminals. Odd? Problem? Parasitic drain somewhere? no 11.5 v is still enough to create enough spark for engine to start (what your seeing is the total of all the voltage drops for each switch and connector in the entire circuit from battery + all the back the battery -, causing slightly lower than true battery voltage)

[zcenterb]

No, I'm unsure if the DME is doing its job or not, i have an unopened working condition in the mail, it will be at my door and in the car for testing by monday. And as far as reaching my testing capabilities, possibly, although ill keep testing things as i think of them, retrace all the wires for sensors, grounds, plugs, etc. Last time i went through a shop for a diagnosis they royally fucked me so.... it would be very nice to avoid that haha. You've been very helpful spdracrm3, much appreciated. Ill keep you posted.

[zcenterb]

spdracrm3 it was the DME. Got a good shape used unopened one today and threw it in and she fired right up! I only paid 1400 for the car too, so a now running IX for less than 1500? Not a bad deal ide say...

[spdracrm3]

very nice , just makes one ask the question why the old ECU went bad .only thing i could think of that would damage a ECU on the coil driver is a bad coil itself or a shorted wiring . hopefully just a fluke failure ,might be worth opening the old one to see if there is any obvious signs of damage ,water intrusion .....

[zcenterb]

Well after i switched them i realized the PO had a shitty aftermarket chip to run special ford injectors or something. So that could have been it. But i replaced the coil anyway just incase. But what i think what I'm going to do i buy new stock injectors and leave the new DME the way it is stock. Ide feel much better doing it that anyway.

Some pictures just for the hell of it.

[zcenterb]

Also the PO told me that when with locking mech went bad on the trunk he put power to it to try and unlock it or something sketchy like that... could have just fried it... Either way it works now, throw in some brandy new injectors, get it registered and inspected, and keep an eye on it and she'll be all set.

[spdracrm3]

hmmm so PO had been into ECU ,who knows what could have happened then

nice clean car ,you'll enjoy it come winter

[zcenterb]

Thanks, much appreciated