88 GXL - no spark
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88 GXL - no spark
I picked up an 88 rx7 GXL a month or so ago for $600. Owner said it ran when he parked it but the fuel pump went bad. New pump (and cleaned and resealed tank... very rusted) And still no start. New ngk plugs and wires and no spark. The coils ohm out ok, as well as the crank position sensor. Per a suggestion from a friend on a local forum, i checked and cleaned the ground on the drivers side shock tower. still no spark.
#4
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Make sure the contact points between the fender and coils are clean for this is how the ignitors within the coil are grounded. No ground equals no spark.
The B/Y wires at the coils require 12 volts w/key to on.
The Brown/White wire at the TPS or boost sensor should read 5 volts w/key to on. A ground signal would probably indicate a grounding caused by the AFM (no good).
The B/Y wires at the coils require 12 volts w/key to on.
The Brown/White wire at the TPS or boost sensor should read 5 volts w/key to on. A ground signal would probably indicate a grounding caused by the AFM (no good).
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im not sure where the TPS is on this car. and im guessing the atmospheric pressure sensor is the same as the boost sensor (same spot in the hayes manual it looks like) i tested it acording to the manual. it reads less than one volt (50 mV) would that cause the coils not to fire?
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The two pressure sensors are not the same. The boost/pressure sensor is in the engine bay at the passenger fender and has 4 wires to it. Black/White, Black, Brown/Red and Brown/White. The Brown/White wire should read 5 volts w/key to on. And make sure you are measuring the proper wire.
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ok, i misread the diagram. the brown/white wire reads 40mV. the manual i have says it the brown/red ... and its 10mV but it does say it needs to be tested with a vacuum applied
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#12
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You need to verify that you are really not getting voltage on the Br/W wire w/key to on. The TPS is Black and located on the very front of the throttle body. It has a piston which extends outward/inward depending on the throttle position. The sensor has but three wires; Green/Red, Black (ground wire thus it should have 0 volts), and a Brown/White wire, which should have 5 volts. W/key to on what does this wire measure?
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im guessing this is the right wire. i got a greed/red, black/white, and like a faded orange. im guesing that last one is the right wire. it reads 43mV with the key on
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i got a few different results. with it unplugged.. at the tps, a few times it would spike to .4v right when pluged in, then drop to .2v The i tested the boost sensor and got 197mV, and the same thing at the AFM. i went back and retested at the tps and got the same 197mV
#18
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The Br/W wire w/key to 'on' should read 5 volts. There are two other sensors supplied by the Br/W wire and they are the variable resistor and ATP. You could start by unplugging all of these devices while measuring the Br/W wire w/key to on in search of the 5 volt value. You could start by having the AFM, pressure sensor and TPS unplugged and test the Br/W wire using the emission side of the harness, which is important,w/key to on
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I havnt had a chance to look at a schematic, but what is the source of the 5v line? Figure I should start checking there. After I unplug the sensor of course.
#23
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With 4 of the 5 it's doing the .4 spike then drops to .2. Tested at the afm plug. Also gets the same at the tps plug.
I havnt had a chance to look at a schematic, but what is the source of the 5v line? Figure I should start checking there. After I unplug the sensor of course.
I havnt had a chance to look at a schematic, but what is the source of the 5v line? Figure I should start checking there. After I unplug the sensor of course.
#25
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You need to remove the Brown/White wire from pin 2A of the plug and then w/the plug connected to the ECU a paper clip could be inserted into the pin position and w/key to on the clip should read 5 volts. Also, with the ECU plug housing pin 2A unplugged you could do a continuity test using the wire in pin 2A and the Brown/White wire at one of the unplugged sensors to see if the wire rings out or not.