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Discussion Starter #1
Hello. I'm posting this because I'm having a strange issue with my Eldorado and I'm becoming desperate to fix it. One day while I was driving home, she started to surge incredibly hard and stall whenever at idle. Somehow I made it home and parked her. I checked the coolant and it hadn't ran out, nor had the car overheated. Checked the battery, and the voltage was fine. The next day, I tried to start the car. It cranked fine, but would not run, so I called my mechanic. He came and looked at her, and found that she was getting plenty of spark but wasn't getting any fuel. She ran fine when he used starting fluid. After taking it to his shop he found that the fuel pump was working fine, and replaced the filter. He looked at how much voltage the injectors were getting and said that they weren't getting any pulses at all, just a solid signal, so he replaced the distributor and the ignition module. The car still didn't start. He told me to check the resistance of the injectors, and said that if one was faulty it could be locking up the entire system, or the ECM is bad. The only other thing I think could cause this is the throttle position sensor, but I feel like the car would still try to start even if it was bad.
I read the codes and the only current ones are I039 (Ride Control Error) and A047 (Low AC).

So tl:dr, my fuel injectors aren't being activated at all and I'm not sure if it's the injectors fault or the ECM. Does one injector failing lock up the system, or is it the ECM going bad? Or something else entirely?

You guys probably know a lot more about these cars than I do, so did I miss anything? Any information helps. Thanks!
 

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Discussion Starter #3
Checked all of the fuses and none were blown. The injectors are getting power but the pcm isn't supplying ground.
 

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-Administrator- 2002.5 F55 STS 2014 FWD Explorer
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Not sure about a '92 4.9, but is there a chance that a faulty security system has locked out the injectors ? Some of these cars use an ignition theft lock; some use fuel delivery theft lock.

Look for diagnostic codes in the car's scanner system. Use the correct year/model instructions in the sticky thread "How to pull codes" on this forum main threads page. You're looking for the OBD1 instructions and the found codes definition link.
 

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Discussion Starter #5
CURRENT
I039 - Loss of Road Sensing Suspension Data - Ride Control Error "SERVICE RIDE CONTROL"
A047 - Low Refrigerant

HISTORY
E030 - ISC RPM out of range
E052 - PCM Memory Reset
I052 - Keep Alive Memory Error
A012 - Low Side Temperature Sensor Circuit
A048 - Low Refrigerant Pressure "VERY LOW REFRIDGERANT, AC COMPRESSOR OFF"
R026 - Driver Initiator Circuit Open
R033 - Steering Diode Shorted in Arming Sensor

I don't think it's the security system, because if it was the car wouldn't even crank. The security light turns off when I put in the key and everything seems to work as normal. The engine just doesn't get any fuel when it cranks
 

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- yes, the 4.9 security controls the injector via data signal to the pcm
- pcm controls injectors via switching of the ground
- the 52 codes are typically set when fuses or battery are pulled. They could have been set off when driving, the pcm lost power.

1) check if a security bypass module was installed. It might have failed. (It simulates the data signal.
2) check wire harness from passkey module or bypass module to the pcm
3) a noid light will provide a better indicator of the pcm switching ground. Cheaper meters won't react fast enough. (Or use an oscilloscope)
4) with a meter, check the ground wires for the pcm and make sure they are looping
5) with a meter, check the wires from the pcm to the injector(s)
 

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Discussion Starter #7
Checked the ground wires and harness, security system doesn't have a bypass and isnt throwing codes either. I'm checking the injectors tomorrow but I decided to take out the pcm just to see if it was stock. When I took out the kick panel, some nuts and leaves fell out, and the pcm had a bunch of rust on it. It wasn't the stock pcm either, it was aftermarket and looked really beat up. Is it possible for water and debris to get behind the kick panel from the vents? I think it would explain a lot, since random stuff on the car liked to just stop working sometimes.
 
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