Ford Truck Enthusiasts Forums

Ford Truck Enthusiasts Forums (https://www.ford-trucks.com/forums/index.php)
-   1999 to 2016 Super Duty (https://www.ford-trucks.com/forums/forum30/)
-   -   88 F350, 460,, wont run right/start (https://www.ford-trucks.com/forums/1202018-88-f350-460-wont-run-right-start.html)

DonKid 11-09-2012 07:11 PM

88 F350, 460,, wont run right/start
 
1988 F350 460,, start/runs good for a short period of time, then misses/back fires,, wont start problem.ffice:office" /><O:p></O:p>
Hey guys hope you can help and thanks in advance for any help..<O:p></O:p>
History of problem.<O:p></O:p>
Was running great until I stopped at a light and noticed and clear miss and the tack jumping while at an idle. As soon as I picked up the RPM’s pass 1200 the miss disappeared and the Tach stops jumping. Over the next 3 or 4 stops (within 3 minutes time) the engine repeated the same situation at each stop but got worse as far as the miss until it was back firing and finally died completely and wouldn’t start. The ford then sat for a few hours and was towed home. Then the engine started up and ran great for 15 seconds and then the same situation took place as before. I could start it but it would miss badly and the tach was jumping. It continued in this manner until it started to back fire and died. Next morning (air temp 50’s) it fired right up and ran smoothly for 10 seconds before the miss and then the back fire started. This morning, with the air temp of 40, it fired up and idled great for 10 minutes before missing and then back firing until dead. I know the air temp shouldn’t seem to make a difference but it does.. Something seem to get warmed up and cause the ford to miss and back fire. <O:p></O:p>
I have discovered.. <O:p></O:p>
While the key is on the check engine light is on, while cranking the check engine light goes out but comes back on periodically as the engine cranks. Sometimes brightly and other times dim.. <O:p></O:p>
I have power to both side of the coil while the key is on and while the engine is cranked. Yet I only get spark from the coil once per revolution of the rotor (fires only on #4 when it won’t start). <O:p></O:p>
Both wires to a fuel injector have power while the key is on,, when the engine is cranking both wire produce a flash of the test light. But one of the two wires of an injector flashes the tester very regularly, the other wire flashes tester very sporadically. <O:p></O:p>
Code reader checks everything OK.<O:p></O:p>
Could low fuel pressure cause my electronic ignition system to shut down?? I ask this because last summer I had a fuel relay go out so it wouldn’t pump fuel to the fuel rail but I had all the spark to the plugs I could use. I was 90 miles from home but able to get home by running a hot wire to the high pressure fuel pump on the frame. What fuel line pressure should I have with the key in the on position? What pressure with the engine idling? <O:p></O:p>
<O:p></O:p>
<O:p></O:p>
To this point I have replaced.. <O:p></O:p>
Ignition module on distributor, coil, plug wires, distributor cap and rotor. Distributor is less than 2 years old. But a remanufactured<O:p></O:p>
Again, thanks in advance for any suggestions on what/where to check next.

DonKid 11-09-2012 08:30 PM

Sorry for putting this on the later model board mods. Please delete this thread because I have repost to the 1987 - 96 board.. Thanks!!!


All times are GMT -5. The time now is 04:34 AM.


© 2024 MH Sub I, LLC dba Internet Brands