93 5.0 RUNNING BAD
Asked by 4wheelman Dec 02, 2015 at 07:32 PM about the 1993 Ford F-150 XLT 4WD SB
Question type: General
MOTOR IS MISSING AT A IDLE, SHAKES, BLOWS BLACK SOOT &
SMOKE DIES ON TAKE OFF, SURGING AT LOW RPM'S, STONG SMELL
OF FUEL OUT THE EXHAUST,HAVING TO RUN IDLE HIGHER ALONG
WITH TIMING, ABOUT 1100-1200 RPMS FOR SMOTHER IDLE RUNS
GOOD AT HIGHER SPEEDS.
CHANGED TPS, O2S, PLUGS, COIL ALSO HAVE CLEANED THROTTLE
BODY & AIR BY PASS ANYBODY HAVING THESE PROBLEMS
17 Answers
You should plug it into a scanner to see if there are any codes that would direct you to a fix. This could be many things.
Have did this and I end up getting Center readings and codes anywhere from coolant temp transmission temp and other mini various sensors but main ones were airflow and exhaust system but was an old hand held flasher unit
Still a guide, sounds like you need someone who knows what that all means look at it. Your motor has issues. But if you are to take a stab at it, start with the catalytic converter, may be starting to get plugged, the O2 sensors could be off, the airflow mass sensor should be changed, along with the idle air control sensor. Timing should be checked, and fuel pressure should be checked. You would change the fuel filter first. That in itself causes some of your symptoms, plugged fuel filter and or low fuel pressure.. These are the things I would look at.
Ok here's what I have done I have change fuel filter air filter co2 sensor throttle position sensor cleaned air throttle sensor unit and mass air flow set the timing makes it reset the computer makes it better for one trip and write back to what it was doing but I could use the input thank you because I'm pulling my hair out for weeks
Only things I haven't done is check the e.g.r valve PVC valve change cap and rotor and plug wires but I already have removed the catalytic converter punched out the second catalytic converter and ran 3 inch pipe into adul outlet flowmaster also have not ran a compression check getting ready to do that now
I got TP sensor I got a new sensor I got coolant temp I got transmission temp I got rich readings I got lean readings course mass air flow throttle sensors just about everyone you can think of in the book and some of them I have no clue what the hell they are I'm an old fashioned kind of guy carburetor points few things go wrong. Not a hundred half of them have nothing to do with the engine and it can still mess it up but I appreciate all the info thank you
You could check for any vacuum leaks but your symptoms sound pretty bad for just that. What condition are the plugs in? Fouled with oil? You might also need to do a leakdown test, with an eye for bad valve seals.
Just did a compression check compression running between 165 and 180 plugs are dark and dry almost I found out look
When you messed with the timing did you remove the "spout" connector, set timing and plug the connector back in?
http://www.fullsizebronco.com/forum/23-technical-write-ups/168214- how-properly-set-timing-302-351-a.html
I guess I didn't do it that way I don't even know what a spout connector is I've always time by ear but I use a timing light set the time and called it good then reset computer where is a spout connector located what is it only reason I'm going through this cuz I can't afford to take it to a shop
Go to the link. It says Bronco, but the engine and wiring is the same. Timing may not solve the problem, but the timing needs to be set properly.......... http://www.fullsizebronco.com/forum/23-technical-write- ups/168214- how-properly-set-timing-302-351-a.html
I'll check it out once again thank you for all your input never any bad input all thoughts on the matter are the best to me
If I can not figure this out can you take a carbureted in take off of a older 302 and dual point distributor all high performance another words bypassing all the new emissions that go along with this truck run run a hot wire to a toggle switch to the coil to the resistor and then to the distributor vacuuming advanced can that be done
sounds like ecm problem. had the same issue with a 94 tbird. replaced the computer with a reflashed one, 135 from advance, ran excellent after. took weeks of frustration to narrow it down to that
No one has posted what the final fix was