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Im not certain this question belongs here so I apologize if it doesn’t. Basically my manual 99 frc cranks over then dies. Its done this in the past twice and randomly decided to start working again. Its doing it again. I have spark, I have fuel pressure. And I have air. Its gotta be electrical right? I replaced the ignition switch. My vats is good. Now my only thought is that my injectors aren’t pulsing, I have a bad ground somewhere or my ecm is shot. Funny thing though… if I hold my key just before the crank position while trying to start it, I can keep it running healthy. I can also keep it running on starter fluid. I have absolutely no idea what the issue is. This all started when I unplugged my battery (I have a new battery now). Unfortunately this is my daily right now so any help would be appreciated. Im checking the injector pulse tonight. Tia
Im not certain this question belongs here so I apologize if it doesn’t. Basically my manual 99 frc cranks over then dies. Its done this in the past twice and randomly decided to start working again. Its doing it again. I have spark, I have fuel pressure. And I have air. Its gotta be electrical right? I replaced the ignition switch. My vats is good. Now my only thought is that my injectors aren’t pulsing, I have a bad ground somewhere or my ecm is shot. Funny thing though… if I hold my key just before the crank position while trying to start it, I can keep it running healthy. I can also keep it running on starter fluid. I have absolutely no idea what the issue is. This all started when I unplugged my battery (I have a new battery now). Unfortunately this is my daily right now so any help would be appreciated. Im checking the injector pulse tonight. Tia
Last edited by lucky131969; Mar 26, 2025 at 12:23 PM.
First off you need to convey to us the correct verbiage…so the car starts and dies ???…if you say it cranks and dies that’s telling me the engine cranks (engine turns over) and starter disengages…cranking and starting are 2 different things…if you think your PCM is shot does the MIL illuminate with the key ON…you can see if you have a 5 volt reference by removing the MAF connector and with key ON see if you see 5 volts on the yellow wire…if you see 5 volts the PCM is “alive”…if the car runs with starter fluid you have a fuel delivery issue…how are you going to check for injector pulse ??…if the car starts and dies this can be a serial data bus issue.
First off you need to convey to us the correct verbiage…so the car starts and dies ???…if you say it cranks and dies that’s telling me the engine cranks (engine turns over) and starter disengages…cranking and starting are 2 different things…if you think your PCM is shot does the MIL illuminate with the key ON…you can see if you have a 5 volt reference by removing the MAF connector and with key ON see if you see 5 volts on the yellow wire…if you see 5 volts the PCM is “alive”…if the car runs with starter fluid you have a fuel delivery issue…how are you going to check for injector pulse ??…if the car starts and dies this can be a serial data bus issue.
my bad. Yeah it starts then dies about a half second after starting. No MIL tho. I had an O2 code bc im catless but its cleared. I was going to check the pulse by using a noid light set (it flashes when inj is pulsing) I will check the MAF when home.
my bad. Yeah it starts then dies about a half second after starting. No MIL tho. I had an O2 code bc im catless but its cleared. I was going to check the pulse by using a noid light set (it flashes when inj is pulsing) I will check the MAF when home.
An aftermarket as in factory level aftermarket ??…I’d check your “fuel enable” data PID while cranking…maybe check your fuel pump relay control wire while cranking…I believe it’s power side switched so you should see 12 volts there or test light illuminated when connected to a good ground.
An aftermarket as in factory level aftermarket ??…I’d check your “fuel enable” data PID while cranking…maybe check your fuel pump relay control wire while cranking…I believe it’s power side switched so you should see 12 volts there or test light illuminated when connected to a good ground.
I checked both of those last night. Nothing unusual
I checked both of those last night. Nothing unusual
Don't know what else to tell you...see if you have any U codes stored and if you can communicate with at least the PCM and BCM and see if you have injector pulse...BTW a noid light doesn't "stress" the injector circuit....injecror circuit draws about 900 mA's....the noid light I don't think even draws 100...if you had no spark AND injector pulse that usually points to a crank sensor...does your Tach move during cranking or do you have an RPM signal cranking with the scan tool ??
Don't know what else to tell you...see if you have any U codes stored and if you can communicate with at least the PCM and BCM and see if you have injector pulse...if you had no spark AND injector pulse that usually points to a crank sensor...does your Tach move during cranking or do you have an RPM signal cranking with the scan tool ??
I have an rpm signal on my reader and my tach moves. I will see if there is U codes. I will check the inj pulse tonight. I definitely have spark, just got all new plugs and checked them all so hopefully not the crank sensor. Again the only reason my brain points to electrical is because this happens when I disconnect my battery to work on wiring. And I can get it to run and rev when my key is held at a very specific point
I have an rpm signal on my reader and my tach moves. I will see if there is U codes. I will check the inj pulse tonight. I definitely have spark, just got all new plugs and checked them all so hopefully not the crank sensor. Again the only reason my brain points to electrical is because this happens when I disconnect my battery to work on wiring. And I can get it to run and rev when my key is held at a very specific point
Oh, now you're saying you worked on some wiring...is that your ignition switch ??...sounds like you have a bad ignition switch,,, where did you buy it ??
Oh, now you're saying you worked on some wiring...is that your ignition switch ??...sounds like you have a bad ignition switch,,, where did you buy it ??
No I bought that to try and fix this. Its not the issue lol. I was working on my stereo trying to swap in a double din
OOOOH a radio installation ???....I've seen a few installs cause serial data bus issues on here over the years...is it all wired up ??...if so I'd undo all the wiring and see if the car starts
OOOOH a radio installation ???....I've seen a few installs cause serial data bus issues on here over the years...is it all wired up ??...if so I'd undo all the wiring and see if the car starts
I mean its wired about the same as it was the last three weeks. Ill unplug it all and check to see if it fixes it. It was running with it like that tho
I mean its wired about the same as it was the last three weeks. Ill unplug it all and check to see if it fixes it. It was running with it like that tho
If you know where Star Connector 1 (has 8 or 9 wires on it) is next to the BCM remove the "comb" or busbar from the top of it and which isolates all the modules to include the radio...now jump the dark and light green wires which will connect the BCM and PCM together and will allow the car to start.
If you know where Star Connector 1 (has 8 or 9 wires on it) is next to the BCM remove the "comb" or busbar from the top of it and which isolates all the modules to include the radio...now jump the dark and light green wires which will connect the BCM and PCM together and will allow the car to start.
If you know where Star Connector 1 (has 8 or 9 wires on it) is next to the BCM remove the "comb" or busbar from the top of it and which isolates all the modules to include the radio...now jump the dark and light green wires which will connect the BCM and PCM together and will allow the car to start.
I unplugged the radio, unfortunately nothing. What do you mean by jumping the wires?
Maybe jump between the 2 Star Connector terminals is better terminology…this is the bus bar removed so wherever you can use to front probe those 2 terminals…light and dark green wires with a length of wire or bend a paper clip into a U and join those 2 terminals that way.
Ecm issue?
