I am having a problem with my '89 F350 4x4 w/ 460. After buying this truck a few months ago I have tried to tune up this ill-running dog to at least make it feel like there is a 460 under the hood. Looking at past posts in this forum on ignition timing checks and advancement, I checked mine and it was off. Thinking this was the reason for the low power I followed outlined procedure: Removed Spout connector from distributor wiring and using a quality timing light I adjusted ignition timing to 10'BTDC, then after shutting engine off, I re-installed Spout connector and restarted engine. It ran smoother but the problem I have now is that after re-installing the Spout connector the ignition timing light says that at idle I have over 20 degrees of initial timing and using the timing light it shows very little advancement when RPM is raised to 2000-2500. I have a code scanner and have no codes other than a code 77 which is operator error code during the KOER test. The only thing I can attribute this to is the ignition timing not comng back down after Spout was reconnected. Would the module on the distributor cause this problem? I took mine to Autozone and they tested it and said it was OK except for a problem with the Dwell, so I had them check a new one before purchase and it too checked bad (brand new) since they didn't have another and not being sure of test results I re-installed mine to keep me going until new one arrives. Has anyone had these type of problems with their ignition. Overall the truck runs OK no sputtering or backfire and it starts up every time but it definitely has a lack of power. PLEASE HELP

Todd
BB79RANCH

 

The Ecu has control over the timing & it will change it based on other inputs from the various engine sensors . What you describe sounds normal . Have a look at basic maintenance items , When were they last checked & or replaced ?

 

Thanks for the reply Paul,
I have replaced the following items: spark plugs, dist. cap, rotor & wires, air filter, TPS, MAP sensor and have checked and/or cleaned: O2 sensor, IAC sensor, Coolant temp sensor & ignition module. I used an ohm meter to check above mentioned sensors and they all passed. Is there anything that I am missing?

Thanks again for your reply.

Todd
BB79RANCH