Solved 1992 Explorer wont start once it is warm

[Josh P]

With OBD1, will wot kill the injectors to clear a flooded engine situation?

 

[spinnn]

Yesterday the fuel pressure while running was holding at 30.5 pounds idling.

Could be intermittent. Can you tape the gauge to the windshield and go for a spin?

 

[allmyEXes]

@spinnn The hose on the gauge is too short to do that. I haven't experienced the warm starting problem this week. Later today, I'm going to take it down the road and back to check out the transmission. Over six years ago the transmission went out and it had to be parked and "wait its turn" to be fixed. I'm glad that I parked it with an empty tank. I was a little surprised that I have one injector possibly not working. Either it was the last one to operate as the tank ran dry or, which is a common theme, I little varmint has nibbled on something. I will be removing the intake as soon as my Rockauto package arrives. Yesterday on Rockauto I was able to purchase FELPRO brand intake and valve cover gaskets on closeout for less than half of what the "cheapies" would have cost. I bought an extra set for my '91. Any of you 4.0 OHV people that need these gaskets better get them now. I think that RA said that it was 30 day closeout.
@Josh P I don't know if WOT kills the injector power on OBD1. Last week I tried it and I may have flooded the engine. The next morning it started right up.

 

[410Fortune]

Seems a little low to me I would rather see 32-36, does it drop and regain quickly if you blurp the throttle

 

[allmyEXes]

@410Fortune I will see when I get over to the shop. Gotta go vote first...

 

[allmyEXes]

Well my transmission test drive didn't go as I was hoping. It wouldn't shift out of 2nd. It's parked in the row again until the gaskets get here and fix the injector. The fuel pump may be going out. I can't diagnose the transmission until I have the correct vacuum pulling on the vacuum modulator.

 

[Louie the Explorer]

Yesterday on Rockauto I was able to purchase FELPRO brand intake and valve cover gaskets on closeout for less than half of what the "cheapies" would have cost. I bought an extra set for my '91. Any of you 4.0 OHV people that need these gaskets better get them now. I think that RA said that it was 30 day closeout.

Thanks for the heads up. Checked and they had one left. After purchase price went up to $73.79.

 

[allmyEXes]

@410Fortune @Josh P @drdoom @CDW6212R I hope to have some time today to remove the upper half of my 1992 4.0 ohv intake manifold. It has been 15 years since I have had one of these apart so I don't quite remember how it is configured. I remember that it didn't have a typical fuel rail but it has a section between the upper and lower half of the intake that the injectors are fixed in to. I'm contemplating how to test the injectors. I don't have the money to go purchase 6 new injectors and just "part swap" them out. Can I remove the upper half of the intake to see the part of the "sandwich" which contains the injectors and have someone turn the engine over to watch the spray pattern of the six injectors to determine which one is not working properly? Or how can I effectively test them?
Yesterday my test drive to test the transmission was a little depressing when I could not get the transmission to shift out of 2nd. It did do the one/two shift so that tells me the governor is functioning. However I have to keep reminding myself that the transmission is not going function properly if the engine vacuum is not at the correct hg measurement. So fix the engine first, then move forward.

 

[LG57]

There are You tube videos of how to bench test injectors with a nine volt battery and carb cleaner. Cheap to do. Also you can remove the spark plugs and crank the engine. You'll be able to tell which cylinders are not getting fuel.

 

[donalds]

I'm contemplating how to test the injectors. I don't have the money to go purchase 6 new injectors and just "part swap"

This works great
Be careful

Fire is not cool

 

[410Fortune]

Yes you can actually hold the entire fuel rail in your hands with the 6 injectors in it and watch it fire
I would not do that, but it is possible

I do this with atv’s that have two injectors

With the ohv once you remove the upper intake (15 minutes) then you have to remove the 6ea double stud that holds the fuel rail down,
Now you have the injectors in your hand
Make a simple tester from old tire stem, jb weld and a carb cleaner straw, use car battery and can of carb cleaner test each one
You can actually clear/clean them this way if you have a clogged nozzle.
Intake gaskets and injector o rings are like $30 Max

The metal upper intake is sooo easy to remove the fuel rail is so easy to access no need to cut corners

Any fuel in the vacuum line to the regulator?

 

[allmyEXes]

@410Fortune I didn't know if I could see the injector/s leaving the plate attached to the lower and looking down in there after removing the top half of the intake. I'm late getting over to my Shop but when i get there I'm going to look for an individual injector tester that I made some years back using a 12 volt computer (PC) power supply, a piece of fuel rail and I can't remember about the pump unless it was one of those 7 pound pumps for a carburetor. Thanks for all of y'all's help. I let this truck sit just a little too long before fixing it, but it could be worse. I'll have to sell it when it is all straightened out. I need the cash to purchase two brand new 1954 F100 doors for ~ $1500- including upgrade door latches. I need fewer total vehicles around here to be working on...
Question: Are the injectors polarized or does it matter which way that I hook up the positive and negative?

 

[410Fortune]

The injectors are
Marked + and - and yes hook them up correctly

7psi may not be enough to spray

You should just use can of carb cleaner as the “fuel pressure”

 

[allmyEXes]

Yeah, I like the carb cleaner idea. Also less FLAMEable too. I just started up the truck and pulled up to the Shop. The transmission pulls with the shifter in OD. I guess this is a good sign

 

[Josh P]

I need fewer total vehicles around here to be working on.

I'm always looking at your inventory of cars when you post about them.

 

[allmyEXes]

I was able to get the top half of the intake removed today. Now I see the 2nd temp sensor. I found a broken vacuum line on the tree that also supplies the vacuum modulator and almost everything else. I knew that it had a vacuum leak the way it was acting. Tomorrow I will pick up on this. Put rags in the intake holes to keep stuff and bugs out. Looks like quite a few things are gonna need moved out of the way on the passenger side to be able to R&R the valve covers. They are leaking a little. I installed this lower mileage long block for my youngest brother 15 to 18 years ago. It is tight and doesn't have any blow by. i didn't see any damaged wiring. I see now how the injectors are positioned.

 

[Fix4Dirt]

I was able to get the top half of the intake removed today. Now I see the 2nd temp sensor. I found a broken vacuum line on the tree that also supplies the vacuum modulator and almost everything else. I knew that it had a vacuum leak the way it was acting. Tomorrow I will pick up on this. Put rags in the intake holes to keep stuff and bugs out. Looks like quite a few things are gonna need moved out of the way on the passenger side to be able to R&R the valve covers. They are leaking a little. I installed this lower mileage long block for my youngest brother 15 to 18 years ago. It is tight and doesn't have any blow by. i didn't see any damaged wiring. I see now how the injectors are positioned.

plannin to change the 2nd sensor? not sure if the vacuum leak would do that for ya, how large was it?

 

[allmyEXes]

@Fix4Dirt I probably should change it. I'll just have to get one and injector O-rings. The broken line was the one headed towards the AC.
ADDED: a.m. 5-26-22 I'm also going to replace the fuel pressure regulator while doing the "tune up".
Yesterday I found my spare fuel pump cartridge which I will go ahead and change too.
This '92 is a good, solid, salt free vehicle worth putting/keeping on the road.

 

[410Fortune]

The 92 is an absolute tank!! Gen I are getting very rare in good shape and they do have a following…. Going up in value!! I would save as many of these trucks as possible and be very proud to own one!!
91-94 are tough as nails!!!! Half million mile trucks when cared for

Long live the ttb! Lol

 

[allmyEXes]

I received my FelPro gaskets late yesterday. I'm glad that I didn't need them right away because it turns out that one of the substitute delivery drivers has been dropping packages at my neighbors carport.
Because I ordered two intake sets and two valve cover gasket sets I have 2 extra plenum/fuel rail gaskets. These are what someone need if they want to install new O-rings on their injectors. Of course you would need to purchase the O-rings somewhere if you were going to do this. I'll sell this pair that are new to anyone with a 1991-94 4.0 OHV engine for cost plus the cost of shipping. $10- would cover all, PayPal (to a friend) would be the easiest way to transact however a Postal Money Order or $10- cash mailed to me would work too.
They may work on other years OHV but I would have to research and crossover part numbers to be sure.