Starting Issues 1999 SOHC Explorer

[sierraoneill]

HI all,

I have a 99 SOHC explorer, just shy of 200k miles, and recently (this winter) developed a starting issue.

I was fearing fuel pump, but I think I’ve ruled that out as it will start and run as normal when getting it going with starting fluid.

When diagnosing the fuel pump I went for the quickest easiest fix and replaced the fuel pump relay, which seemed to make things better, but may not changed anything as the temperature was in the 50’s. Now that it’s even colder out (20-30’s, only way to get it started is by using starter fluid When it is “sat overnight cold”

My searches on the forum have had me get an Intake Maniforld gasket kit (upper and lower) which I now have in hand ($15 so I like the price on this fix so far).

Question is before I spend several hours replacing them, should I replace anything else at the same time I have the Intake all disassembled?

Any opinions that I may be going not going about this the right way?? If it needs a new fuel pump, I would likely have to take it to a mechanic as I would have difficulty dropping the tank to replace it…which may mean junk yard for the old car given the cost of having someone do that work and the values of the car.

Thanks in Advance!!

 

[donalds]

The upper intake screws .......only hand tight or you will strip them
Trust me on this or it will cost you $100 for a lower intake
I'd do the Pcv valve motorcraft only ...and save your old one
Test your fuel pressure ...only way to know ...
Rent one cheap at your auto parts store
Here is a thread I made on how to replace your pump

Is my fuel pump bad 1999 ford explorer shoc 4.0. Lots of pictures on the replacement

How can I explain this

www.explorerforum.com

I own a 99 to link below in my signature

 

[J_C]

I'd first check your battery voltage. On one occasion when I had trouble starting in cold weather, it was a combination of wearing out battery (low voltage after sitting) along with old spark plugs. I changed plugs and wires and that helped, but ultimately a few months later the battery was kaput.

Partially clogged fuel injectors can also cause poor vaporization of fuel, especially with cold cylinder walls. I'd also try a bottle of Techron fuel system cleaner.

You can measure your fuel pressure but i doubt that's it since it runs once started, especially if not bogging down under load. Before doing the manifold gaskets I'd use a scan tool capable of live data to look at long term fuel trims. If you have a vac leak significant enough to prevent starting, fuel trims would probably be above single digit positive.

Some people cut an access hole to replace a fuel pump instead of dropping the tank, but IMO it's not especially hard to drop the tank if you siphon as much gas out as possible first (pull the fuel filler tube hose at the tank to make this easier) then put a piece of plywood of greater dimensions, onto a floor jack saddle to spread out the tank contact area. Once the tank is down you can drain the rest of the fuel out so it weighs less and is easier to get back on. Frankly it is easier than doing the intake manifolds, unless you have a bad back or lack a floor jack.

Heh, not like you should pick based on which is easier when you can get a loaner tool, fuel pump gauge from an auto parts store.

Either way I'd want more evidence collection before replacing things, though if you have very old spark plugs and wires, they're considered a wear item so I'd go ahead and do that... even if they were replaced at the first 100K mi service interval, they're now at another 100K mi interval again or might not last that long if not double platinum or better.

 

[sierraoneill]

Thanks for those replies!

I’m wanting to test the fuel pressure before I go for the gaskets, but I’m thinking probably not the issue give the thing runs normal once it is running.…. But I will see if I can get a gauge to do that just to know.

As for plugs and wires, probably 50k mile, and fuel filter is < 3k miles so that can be ruled out.

I can’t find the thread, but it seemed like there were multiple people saying intake gaskets…..but since the thing idles fine, I’m starting to wonder if that may not be the issue (?)

As for fuel pump… I also have an E350 van,… cut a hole in the floor to do that one, so I know that trick all too well!!!

 

[J_C]

There are multiple things that can cause problems starting. Reverse engineering from... I have bad head gaskets... so it's hard to start, is different than... it's hard to start... so I have bad head gaskets.

You could even have a bad temperature sensor. Hooking up a scan tool capable of live data is very useful. It may not always find the problem, but is a lot less work than shotgunning parts replacement if it does find something.

I usually use a BAFX I got off amazon for ~$22, works over bluetooth with my android phone, just leave it in the glovebox. BAFX also makes a wifi version, handier for Apple or a PC, longer range wifi link. I should clarify that I use Torque (free version) and Forscan Lite (paid $6 version), but Forscan also has a free demo version that can read one parameter at a time. You should be able to get enough done with the free version of either of those, for now. Forscan is better, handles Ford-unique codes that Torque doesn't. The software that comes with it on the included CD is old garbage, do not use.

I just noticed the bluetooth version is at the cheapest sale price I've ever seen it, $16:

Amazon product ASIN B005NLQAHS