My 1993 Bronco 5.0 will run great for a while then start spitting and sputtering like it's running out of fuel and lose power. I can let it sit for awhile and it will run great then start acting up again. My son drove it for a couple weeks with no problems at all. We bought it from an individual who did some modifications and removed to smog pump. The Bronco is a `1993 model with a crate engine wiht less than 50k miles. I've replaced the fuel filter. Any suggestions much appreciated.

 

Check key on engine off (KOEO) fault codes and fuel pressure.

 

I would do both tests and the fuel pressure test
KOEO and KOER
I would reinstall the air pump and the valves bypass and diverter, TAB and TAD solenoids
It will not cause you any trouble with power loss (negligible)
Low fuel pressure is liable to be your problem

 

The process is to repair any engine off codes before moving on to the engine running test.

Unless the previous owner gave the OP all the removed parts that could be expensive and a waste of time. As long as the TAB & TAD solenoids are plugged in, the computer doesn’t know anything else.

Low fuel pressure or a failing ICM could be the at fault. IMO, it is way too early to say what could be the problem since no diagnostic testing has been done which I why I didn’t say anything about a certain part.

 

A peek inside the ECM to make sure you don't have failing capacitors may be in order.

 

I'm not new to Fords but new to old Broncos. I'm pretty sure the TAB and TAD solenoids are present and plugged in. It looks like the previous owner replaced all vacuum lines with rubber tubing. You mentioned ICM, is that the same as an ECM? The ECM on the truck was recently replaced just prior to our purchase, The alternator was putting out way too much voltage and was blowing the ECM. The previous owner prior to finding the alternator issue had replaced almost every sensor trying to find the engine problem. I'm beginning to think fuel pressure. I replaced the fuel filter and ran some fuel out ot the hose from the tank into a jar. It looked clean and clear. I dumped what was in the filter and it was full of fine debris like sand. It was muddy looking. I'm going to drop the tank and inspect the inside. I haven't replaced the fuel pressure regulator since the guy at Oriellys said if it was bad the fuel would run back to the tank and be hard to start until the fuel pumped back up. There is a slight vacuum to the fuel pressure regulator and there is no fuel residue in the vacuum line. Thanks for all the info and any other suggestions are greatly appreciated.

 

The Ignition Control Module (ICM) is mounted on the distributor or on the driver’s fender (later model years). An ECM is the Engine Control Module or engine computer.

 

A 93 ICM should be mounted under drivers side hood hinge.
The 93 ECM is near there but lower and mounted in the firewall.
Several years back my 93 all of a sudden was running like it had bad gasoline. Stumbling and hesitating.
Out of curiosity I pulled ECM and low and behold the capacitors were oozing all over the place.
Cleaned up the board and replaced the leaking capacitors and not a problem since.

 

Hey Marine, Did you solve this issue?