GTS died
01-23-2009, 06:42 PM
#1
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GTS died
Was at a friends house the other night and when I left later on to fire up the car, no start. I tried several times, but no worky. Had to have it flatbedded back to my house.
Starter cranks, turns engine but won't fire up. Checked the EZK and the LH in another 93 GTS and both are fine. Replaced the crank position sensor with a known good one and that made no difference.
Fuel pump fuse and relay are fine, pump runs when key is in position #2.
Checked spark at a plug wire and that didn't go well...arced twice with several cranks. Tach jumped when it did spark, but other wise no tach movement while cranking.
Marked T belt to make sure it was OK and it is after cranking.
No fuel smell, but that is to be expected as the brain is not opening the injectors due to some other electrical malfunction.
Anybody got a "where to next" ?
Thanks
NOTE: FIXED...SEE PAGE 13
Starter cranks, turns engine but won't fire up. Checked the EZK and the LH in another 93 GTS and both are fine. Replaced the crank position sensor with a known good one and that made no difference.
Fuel pump fuse and relay are fine, pump runs when key is in position #2.
Checked spark at a plug wire and that didn't go well...arced twice with several cranks. Tach jumped when it did spark, but other wise no tach movement while cranking.
Marked T belt to make sure it was OK and it is after cranking.
No fuel smell, but that is to be expected as the brain is not opening the injectors due to some other electrical malfunction.
Anybody got a "where to next" ?
Thanks
NOTE: FIXED...SEE PAGE 13
Last edited by 928ntslow; 02-22-2009 at 09:45 PM.
01-23-2009, 07:12 PM
#5
Under the Lift
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Jumper (temporarily) or replace fuel pump, EZK and LH relays.
A noid light on one of the injectors would help to verify if they are firing. John Speake's Spanner or Theo's diagnostic tool can be used to test the injector circuit as well.
I know many decry this as dangerous, but a short spray of starter fluid down the MAF throat can help nail down spark versus fuel. If the engine briefly starts, then you have fuel supply issue. It's been helpful to me many times.
Note that a short in any of the injector leads will disable all injectors. Not high on the list unless you recently manipulated the injectors, but it will cause a complete no-start, as I have seen in one local GT. The noid light was our clue after verifying that all the relevant brains, fuses and relays were working.
A noid light on one of the injectors would help to verify if they are firing. John Speake's Spanner or Theo's diagnostic tool can be used to test the injector circuit as well.
I know many decry this as dangerous, but a short spray of starter fluid down the MAF throat can help nail down spark versus fuel. If the engine briefly starts, then you have fuel supply issue. It's been helpful to me many times.
Note that a short in any of the injector leads will disable all injectors. Not high on the list unless you recently manipulated the injectors, but it will cause a complete no-start, as I have seen in one local GT. The noid light was our clue after verifying that all the relevant brains, fuses and relays were working.
01-23-2009, 07:17 PM
#7
Team Owner
What was the last thing you fixed/washed/ looked at
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01-23-2009, 07:22 PM
#8
Fuel pump will not run with the Key in #2. That's the PSD pump pumping up.
Are you sure the fuel pumps are running? Have you jumpered the relay?
Are you sure the fuel pumps are running? Have you jumpered the relay?
01-23-2009, 07:24 PM
#9
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Ran great as usual. Out of the blue, no start. Haven't done any work to the engine in a looooong time. Last major change was an X pipe.
Keep in mind this is a near new car and has not been F'd with and well taken care of.
Keep in mind this is a near new car and has not been F'd with and well taken care of.
01-23-2009, 07:25 PM
#10
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Keith - You can check the relay operation by checking for power on one of the injector connectors...
If the EZK is generating spark (seems it is) - it thinks it has its timing correct - it will not generate spark if it is unhappy with its sensor inputs: TPS/WOT/Coding/RPM Sensor/Hall Sensor/Knock sensors/AT protection switch/ Eng temp - however most of these sensors are not critical to run - (though maybe badly)
The LH will not fire the injectors unless the EZK is happy and is generating spark - detected via the Engine Speed signal from EZK
The LH also relies on: MAF/TPS/WOT/Engine temperature/AC compressor/Fuel Type/OXY Sensor/Coding/AT idle drop (again most are not critical to trying to run)
Alan
If the EZK is generating spark (seems it is) - it thinks it has its timing correct - it will not generate spark if it is unhappy with its sensor inputs: TPS/WOT/Coding/RPM Sensor/Hall Sensor/Knock sensors/AT protection switch/ Eng temp - however most of these sensors are not critical to run - (though maybe badly)
The LH will not fire the injectors unless the EZK is happy and is generating spark - detected via the Engine Speed signal from EZK
The LH also relies on: MAF/TPS/WOT/Engine temperature/AC compressor/Fuel Type/OXY Sensor/Coding/AT idle drop (again most are not critical to trying to run)
Alan
just "new" relative to the OTHER 928s..... does your GTS have an alarm system ?
01-23-2009, 07:33 PM
#12
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Jim all unmolested GTS's have alarms - so yes - good point
Check the XXII relay pin 86 it should be 12v with the ignition on - else the alarm is the issue
Alan
Check the XXII relay pin 86 it should be 12v with the ignition on - else the alarm is the issue
Alan
01-23-2009, 08:37 PM
#15
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OK..
Just checked the injectors..they are getting voltage
Swapped relays, no difference, checked relays they all work...did this with a 9v battery and a multi meter.
I also checked the fuel delivery. I opened a fuel line and relieved the pressure. Cranked it several times and then opened the line again...no fuel. Thinkin' its the pump now.
To check voltage at the pump, does the key need to be turned to the #3 position to get voltage? Can I also disconnect the leads and throw 12v's at it to see if it runs?
Funny, you don't fix a problem for a while and the memory of diagnosing things goes right out the door!
Just checked the injectors..they are getting voltage
Swapped relays, no difference, checked relays they all work...did this with a 9v battery and a multi meter.
I also checked the fuel delivery. I opened a fuel line and relieved the pressure. Cranked it several times and then opened the line again...no fuel. Thinkin' its the pump now.
To check voltage at the pump, does the key need to be turned to the #3 position to get voltage? Can I also disconnect the leads and throw 12v's at it to see if it runs?
Funny, you don't fix a problem for a while and the memory of diagnosing things goes right out the door!