My F-150 (351) 1995 XLT has been knocking but last night when
I (Twice) was driving up a steady hill (Not all that steep just long) I kept loosing exceleration and could only go about 35mph without just flooring it but it feels like if I did floor it, it would break sorta speak.

The last time I was on here discussing that Air Intake Valve that was replaced last year when the truck was knocking them. This seems to be a bit different but this forum recommends a tune up with new plugs and 8mm wires also.

Anyway, I'd like to here some input on what I can replace myself and if it seems rational to change the Plugs and Wires or should I look elsewhere for this loss of exceleration on hills. What could cause that?

Thanks
David

 

If the spark plugs and wires haven't been changed in awhile check them out, if they are a brand other than autolite or motorcraft copper or similar then replace them. Newer platinums don't work as well. Make sure wires aren't cracked/boots. If its 100,000mi or over on the original change them.

Also, check distributor and ignition coil. Change the fuel filter, most people like me just change it out, its a bit of an annoyance () but defiantly can be done yourself or cheaply by Jiffy Lube. Its cheap to change at $7 but most people don't do it and it clogs fuel flow when dirty.

Checking codes, won't tell you the problem necessarily because it may be a cover up because the comp is compensating, but at least we can help you a bit more. (Don' change parts on bases of code readings) Yes there may be codes even though the check engine light is not on. (You can search on this site for how to check codes or it may be in the sticky at the top of this era's forum too)


So your order of business is A. check codes, B. wait for smarter people on here to tell you really what to do and C. change fuel filter and at least check plugs wires rotor and coil for damage/wear. Pull a couple plugs out and check for fouling too if you don't change them. Check timing and fuel pressure if you can.


You can do all this yourself. Plugs and wires are easy if you have a socket set, you need a sparkplug socket. Also I flatly state you must get a haynes manual at your local auto repair store it will walk you through that job, a fuel filter job, and check distributor, coil, timing etc. It will tell you how to do a tuneup.

It depends how much you want to invest in learning and tools. Do you need the truck up and running right away? Then take it to a mechanic, you can learn how to do this stuff later. The tune-up for my truck was $300, of course I had a laundry list of things to do extra I also did several stuff before the tuneup, that isn't normally a part of it, which took my time away from doing the reg tuneup so I had it done at a mechanic because I needed my truck for work.

A tuneup may not fix your problem, but will definately help eliminate many things, plus it will help a bit with mpgs, general good running, peace of mind, and will eliminate problems in the future.

Later,
Paul

P.S. The reason I am not helping with the pinging and loss of power is that in my experience I have seen many things cause this, so I am waiting for someone smarter to answer that knows where to start

 

Your motor is suffering heavy detonation, this is not good and will do permanent damage if it isn't fixed. If there are no codes thrown you may have a bad vacuum leak or a rusted out or malfunctioning thermactor(air injection) system or EGR. Check the codes first and go from there.

 

check for a clogged convertor or exhaust system.

 

Sorry guys, I was thinking in my mind pinging. I think I needed more coffee this morning. Thanks quicklook and Paul for setting me straight!!

Later,
Paul

 

All,

Ok. Great. I'll do the tuneup, fuel filter sounds smart and easy to do. Clogged convertor or Exhaust would make sense to me too but how to you check that?

 

use a vacuum gauge to check backpressure.

do you have platinum plugs in now?

 

Quicklook

I have not gotten a tuneup in awhile. They are cheap plugs in now. Where do I use the Vacuume guage to check backpressure (I'll check in my Ford book about this) but what if it's low pressure? What are you thinking about regarding pressure?

 

also check the timing. pull the spout connector and make sure timing is at 10*btdc.