Hi there, I'm hoping y'all can help me. When accelerating on an on-ramp or up a hill my Expy engine stalls for a split second intermittently. The tach goes to zero then a second later everything is fine. It might go two or three days before doing it again. The electronics (lights, radio, etc.) stay on. My Expy has 175K on the original engine and tranny. Any thoughts?

 

Sounds more like an electrical power loss because of the tach dropping off. You might want to start shaking wires to see if you can recreate the issue.

 

Hi, Scooter. This sounds similar to what happened with my 99 Expy starting around a year ago. I didn't get OBD codes until around 10 months later as it got progressively worse. Quite frustrating...

Bottom Line: Could be carbon build up in and around your throttle body and corresponding EGR ports. I also had bad MAF, TPS, and DPFE sensors problems.

Here's the link to my maintenance journal:
https://www.ford-trucks.com/forums/1...e-journal.html

Good luck!

 

Is the battery strong? When my failing alternator brushes started to create intermittent charging, the gauges fell off when the battery became relatively discharged.
The engine sputtered but would barely restart with weak battery due to the lack of charging.

 

I have a 2003 Lincoln Navigator with the 5.4 V8. When I would accelerate or put a load on the engine, it would shutter, almost like it would die. If you kept putting the gas to it, it would stall out. However, we found out that if you let off the gas and 'unloaded' the engine, it would idle down and you could save it. Either way, not a good way to drive the vehicle.

Problem? Bad Ignition Coil. I replaced all 8 ignition coils along with spark plugs and wa-la! Problem solved. I have about 200K on my Navigator now, the first time I changed out the coils and plugs was at 100K and I paid the dealer to do it (about $850 at the time). Now, I just did it my self. I really had no way of testing ignition coils, so that is why I changed out all 8. If you have a way to test them, then that can save you some money too.

Just something for you to consider. I read the comment on the throttle body, and yes, that is a good comment. I would agree and recommend you clean that too with some good throttle body cleaner. ($3.50). I did it to mine and had a much improved acceleration response. I was surprised how dirty it was.

Hope this helps.

 

Here is a video that may help you in replacing the ignition coils, if you plan to do it yourself. I was able to complete my work in about 2 hours, but I took my time and went slowly.