PollyRDH98

Thanks for all the info and suggestions! This forum is great, I've been reading it since we bought my son the 1990 several weeks ago.

Everything I've done so far needed to be done badly, so I really haven't spent money that was unnecessary at this point. Fuel filter was possibly the only thing that wasn't absolutely necessary, but the guy who owned the truck before was very negligent with general maintenance that it was probably a good idea anyway. Spark plugs were nasty and corroded. The TPS practically crumbled apart when I removed the TB and the engine ran strong (and stopped stalling out) after I put it all back together.

So, my duh! moment was that it couldn't be the fuel pump since the truck has duel tanks (right?) with a pump on each one. Unless they both coincidentally (and unlikely) went out at once. There apparently is spark in the plugs since I can get it started and running as long as I'm spraying starter fluid in the TB.

Checked all the fuses a couple of weeks ago, they all look good. Not sure how to check all the vacuum other than the obvious (just looking to be sure that they are connected and nothing has a hole in it) and I've done that. I even took the throttle body back off to be sure I had everything hooked and plugged back up right.

Went and talked to some guys at a shop up the road yesterday and am probably just going to tow it up there.

Cracked me up about the dimmer switch there. Had to show my (17 y/o) son how to find it, too. In fact, he told me his wipers were broken because they would only come on once then stop. He kept turning them on and off the whole way home. When I looked, I noticed that you turn the **** left for intermittent and right for low/high. He was only turning it to intermittent, therefore thought they weren't working.. lol.

Warlockk

Did you get a chance to check for error codes? Is the cel light on. The codes can be telling and its worth the ten minutes even if you decide to take it in. Information is power after all. I know what you mean about maintainence. Just about every major repair I had to make on my 90 could have been avoided if the previous owner had changed the fluids every 100k miles or 10th years. I had to replace the master cylinder, transmissions, power steering pump, cooling pump, and rear gears. Fortunately the engine had been rebuilt or I'm sure the oil would be non existent and the truck useless. The fluids looked like coffee with a leaky filter. Amazing what people will do to their vehicles.

PollyRDH98

Yes, the ce light is on. Haven't checked codes because I don't have a code reader. Wasn't sure it was worth the investment for me because I won't be able to get into anything too complicated myself.

Might replace the fuel pump relay (since it's a $15 part) before towing it. Just going to do a few final checks and troubleshooting today and will get it towed if I can't figure out anything today.

PollyRDH98

Found out how to read codes without a reader. This is what I have:

121, 556, 565

PollyRDH98

All the codes were KOEO, since I can't start the engine.

121 (Closed throttle TPS voltage higher or lower than expected.) I read that this particular TPS isn't adjustable. Is that not accurate? It cannot be turned at all when it is installed, which is how I read that TPS's were adjusted.

556 (Fuel Pump circuit failure.) Dual tanks, dual pumps, so fuel pump itself is ruled out. Relay is cycling on/off when key is turned to "on."

565 (Canister purge circuit failure.) Read that these rarely fail. Will check the vacuum lines going in/out of this unit tomorrow.

If anyone has any further suggestions, I would love to hear them. As a single mom, I'm doing all I can to avoid an expensive repair bill. Biggest fear is being ripped off. At any rate, I don't have hundreds of dollars to pay a shop if it's something we can do here at home.

Warlockk

Tomorrow I can check Fords database and see what I can find. I'm a bit suspect of the fuel circuit. It fits your symptoms. Check the tps for loose or bad wires and connections. If you have a dmm check for voltage drops and high resistance.

southernyankey1

you should be able to get a free code scan at autozone or advance autoparts...

the obd reader for a 90 is only like 30 bucks or so.

Forge-World-FORD

Not for OBD 1. Every place I asked, before I bought my code reader, only did OBD 2.

Good old Bill

You still could have an issue with the pump, or actually the switching valve. I am assuming this truck still doesn't run, so all your codes are in memory. Its good to right these codes down, clear the memory and proceed to get this critter started. You said it starts with starting fluid, so I'm assuming your don't have fuel to the rail. You really need to depress the schraeder valve on the rail and be careful of the fuel spray. That is of course if the pump is working.

PollyRDH98

Correct, the truck doesn't run at this point. I reset the codes and still get the same ones. 121, 556, 565.

After trying to start it, I depressed the Schrader valve, and didn't get a gas spray or feel any pressure released. Tried to start the truck with both gas tanks.

Also, I cannot find the Canister Purge solenoid. I think it has been removed from the truck. There is a small hose (one of several) that is coming out the top of the engine that is plugged off with a screw. I'm wondering if that's where the canister purge solenoid was connected before?? Not sure if it even matters if that's how it has been for some time. The guy who had the truck before rigged some things up that weren't quite right... the radiator is even too large for this model, but he had it rigged in there anyway.