How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask AZTechBrian Your Own Question
AZTechBrian, ASE Certified Technician
Category: RV
Satisfied Customers: 708
Experience:  Owner
Type Your RV Question Here...
AZTechBrian is online now
A new question is answered every 9 seconds

I have a misfire problem with my 1994 Ford Motorhome (460).

Customer Question

I have a misfire problem with my 1994 Ford Motorhome (460). The plugs and wires have been replaced. Looking for other ideas. Is there a known issue with this motor having this problem. The vehicle only has 60,000 miles.
JA: How many miles are on the car? Is it a steady misfire? Or random?
Customer: It's a steady misfire at idle.
JA: What is the model of your '94 Ford?
Customer: E350 Motorhome
JA: Are you hoping to fix this yourself? What have you tried so far?
Customer: I had a mechanic replace plugs and wires. I'm not sure if he replaced other electrical components or not. I will have some time during the week of labor day, so I'm hoping to take a crack at fixing the problem myself.
JA: Anything else you think the mechanic should know?
Customer: Not that I can think of???
Submitted: 5 months ago.
Category: RV
Expert:  AZTechBrian replied 5 months ago.

Hello. This misfire is only present at idle? It runs fine in the higher rpm?

Customer: replied 5 months ago.
True. It seems to run fine at higher RPM. Although, maybe I'm not getting the gas mileage I should be getting.
Expert:  AZTechBrian replied 5 months ago.

Ok. I suspect you have replaced the cap and rotor when you did the plugs and wires? I would do that since those are regular maintenance items and often times resolve rough running conditions. It does sound though like a vacuum leak. Often times due to a bad egr valve. Has that been replaced? Have you looked over all vacuum lines under the hood and looked for any signs of damaged or crumbling vacuum lines? listened for a sucking type sound when idling?

Customer: replied 5 months ago.
I will try this.
Expert:  AZTechBrian replied 5 months ago.

Yes. please check over the vacuum lines well, listen for whistling or sucking type sounds, etc. Replace cap and rotor as well. Please let me know how that goes and if the problem has not been identified at that point, we will keep at it until we figure it out.

Customer: replied 5 months ago.
It's too soon to offer a rating. I will attempt the repair next week. Thanks!
Expert:  AZTechBrian replied 5 months ago.

No worries. The reminders to rate are automatically sent out. I dont have control over it. Let me know if you need anything else.