im posting here since this is the engine section..doh! anyway here is my problem

i have a 1988 formula 350, the other day it ran fine, then wouldnt start the other day, it just cranks, and will fire, and you can rev the engine while the starter is engaging, but once you let the key flip back into on position it will not stay running and either dies, or stumbles,dies,stumbles,dies and then give up completley. I know it must be ignition related, as it will rev, meaning it gets plenty of fuel and air, meaning the relays must be intact. However i think it could be the ignition module, as i think it takes over for firing after the starter dissengages, i found this trouble code, but im not sure if mine puts it out since i do not own a scanner, but it sounds similar to my situation.

any help would be greatly appreciated, thansk guys

Trouble Code 42 indicates that there may be a malfunction in the Electronic Spark Timing (EST) system.

During cranking, the timing is controlled by the ignition module while the ECM monitors the engine speed. When the engine speed exceeds 400 RPM, the ECM sends a BYPASS signal to the ignition module which switches the timing to ECM control. The ECM calculates what the timing should be then "tells" the ignition module via the EST circuit.

An open or ground in the EST circuit will stall the engine and set a Code 42. The engine can be re-started but it will run on ignition module timing.

The conditions for setting this code are:

* System in BYPASS mode but the ignition module is still controlling timing

- or -

* Engine speed > 600 RPM with no EST pulses (ECM controlled timing) going to the ignition module for 200 msec.


Typical causes for this code include:

1) BYPASS line is open or grounded
2) EST line is open or grounded
3) PROM or CALPACK not seated properly in the ECM
4) Poor connections between ignition module and ECM
5) Poor routing of EST harness and/or poor quality ignition wires (EMI induced electrical noise)
6) Faulty or incorrect ignition module
7) Faulty ECM

 

You probably won't need a scanner, only a voltmeter.

Make sure there is 12V to the ignition module when the ignition switch is in RUN, and not only while cranking.

 

ok ill check that tomorow, ill run to wal mart and get one. I tried to start it again and it simply wont run after i let the key go, it will usually stumble, die, then stumble again, then die again and do it once more then die. I'm not sure what could cause that symptom other than ignition or the computer itself, i dont think it would have run like it did with a bad wire.