Im stumped with my Bronco.. 1988 4x4 5.0 XLT Bronco I put new plugs, wires new fuel filter new Alternator fixed two vacuum leaks and it still spits and sputters at low rpm's i also timed it to where the sticker told me too, 10 degrees before and tho it runs better everytime i do something, theres room for improvement PLEASE anyone who can give me a hint to what else i can do would be greatly appreciated!!! I love this bronco and i'd hate to put him to sleep.........I'm changing the cap and rotor this weekend hoping it will help.

 

any help???????

 

New filter on the gas pump in the fuel tank. It's helped my DonKo, now I have to fix the rusted water pump. New filter costs about 5.

 

First a big welcome to FTE. There are many good folks here who will do their best to help.

For your situation I would start with plug wires and be sure they are all connected good. Check your firing order, double check your wiring. Two adjacent cylinders fire sequentially..either 7-8 or 6-5. Separate those wires in the wiring looms are far as possible to prevent cross firing. Check for a cracked plug and carbon tracking. Use copper plugs. Now, I will lose my credibility...I found a plug I did not tighten good on mine on the last tune up which made your driving condition. If oxygen sensor(s) have 90K they may need replacement even if codes pass.

Pull codes and read up on the sensors using Ford Fuel Injection.

 

I am with B4hntn, crossfiring plug wires is a common issue with the 302 and 351. Routing of the wires is very important in assuring the cross firing is at a minimum. On the drivers side a simple rule is to have 5-7-6-8 wires run in the wire seperators so that adjecent cylinders wires are not next to one another. 1-3-2-4 for the passenger side as well. I also made use of the plastic wiring looms that were just big enough for a single wire to help in seperation and added insulation for preventing cross firing. The wire runs are tight on the passenger side due to the intake but it is possible to run the wires so that crossfiring is reduced. Good luck.

 

Check for codes. The light need not be on for them to exist. All you need is a paperclip. Check out www.fordfuelinjection.com for more info. Good Luck