LBGSHI

Apologies, as this will probably be verbose; I just want to give as much detail as possible.

So, I took my 18-year-old step-daughter to a used car lot to buy her first car. Nothing fancy, just something that'll run for a couple years before she probably gets a better car. Despite there being newer, cleaner, more girly cars in the lot, she went straight for the 1987 Ford F150. It ran rough at low idle, and if you didn't baby it a little, it would die on you, but once it was warmed up, it ran like a monster (a beautiful monster). The rough idle occurred whether in park, reverse, neutral, or drive, and I figured there was probably a vacuum leak, or maybe an intake problem, and it probably needed a general tune-up (plugs, wires, ignition coil, etc). They'd apparently just fixed some issues with the brakes, and they seemed to be working fine. AC wasn't working, but after the dealer added some R12, it gave ice cold air, but obviously a leak was present, which I'd fix later or replace the AC system with an R134a one. For just under $2000, it was worth the work, and I loved the truck once we started it and took it for a spin.

Well, she learned to baby the engine over the next couple days, loved the truck, and everything was fine. Then she called me, right outside the gate of our apartment complex, saying it had stalled out and she couldn't get it started. I wasn't home, but her brother came out and helped her get it pushed into a parking spot so I could take a look when I got back.

I figured, it runs rich, and has a rough idle, let's replace the plugs first; they're probably fouled, and old anyway. So I grabbed 8 plugs, swapped them out, started the engine (after a couple tries), and it ran, but still very rough - worse than when we bought it (once you let off the gas, it sputtered and died, making it undriveable). The old plugs were OLD...felt like the original plugs (rusty, almost impossible to remove, caked in carbon).

While I was at it, I took some carb/choke cleaner, and hunted for vacuum leaks, but couldn't get it to rev a bit more no matter where I sprayed. It could be that I missed the vacuum leak, but it could also be that there isn't one.

Next, I bought new plug wires (including the wire for the ignition coil), and replaced those. It definitely started a little easier after that, and ran much more smoothly (those old boots were falling apart, rusty inside, etc), but it was still not really driveable.

Next step was to replace the ignition coil: when I replaced the wire for the old one, I noticed that the coil was scorched badly, and fairly rusty. After replacement, there may have been a mild improvement, but it may have been in my head. Anyway, a good investment.

Switching between the two gas tanks didn't seem to make a difference. And I'm running 93 octane (Supreme) gas, in case that's a concern).

Something strange I noticed was that when I revved the engine, and let it idle low again, the oil meter would fluctuate. Not dramatically, but by a quarter of a tank or so. It would also stay between half and 1/4, even though the dipstick is telling me it's chock full.

Another minor strangeness was that, as the car was idling, if I pressed on the brake, I could hear the car rev just a tiny bit higher for a second, then flatten back out again. Then, when I released the brake, it revved just a little bit higher than when I pressed it in, and then flattened out again as well. Perhaps that's normal. I remember hearing/reading that the brake system provides vacuum for the engine, so it's not beyond possibility that the new brake job they did screwed up the vacuum, or something. Please do let me know if there's a quick test I can perform in that regard.

Next, I decided to remove the IAC (Intake Air Control) valve/sensor, and clean it if necessary. After removing it, it turned out that it wasn't that dirty at all - just a light layer of carbon, which I'd imagine is normal. I reinstalled it (using the existing gasket for the time being, as it didn't seem too worn and I had bigger fish to fry).

Someone mentioned that I should see if the TPS (Throttle Position Sensor) was operating properly or not. According to this guy (an Advance Auto employee who apparently worked as a mechanic prior to that), if I disconnect the TPS, and there's no difference, the TPS is shot and is probably the issue. If there's a noticeable change, it's probably not the TPS (or at least, the TPS is operating to some extent). I did so, and there was a considerable drop in idle, and it ran choppy before I killed it because I hate to let it die on its own. So, I assume this means the issue isn't the TPS...but please correct me if that's a flawed assumption.

I also cleaned and reseated the connector on the EGR valve sensor, but didn't pull/clean the EGR valve itself, as I was told that it wouldn't be feasible to disassemble it enough to clean it considerably. I suppose I could replace the EGR valve sensor if it comes to it.

After considerable testing, starting it, running it, feathering it, warming it up enough to let it idle on its own for a few minutes with no gas pedal interaction, listening to it, looking for anything out of the ordinary, I decided that maybe it was healthy enough to run it a couple miles down the road to that Advance Auto, as they'd offered to listen to it and see what they could determine (free advice; why not?). I hopped in, put it in reverse, pulled out a few feet, and it started sputtering. If I gave it gas, it would have been fine, but there was a wall behind me, so I would have smashed into that. I dropped it back into drive, pulled it back into the parking spot, and it choked. I wasn't worried, as it had done so quite a few times so far. I gave it a couple seconds, then turned the key, but - nothing. No crank, no starter noise at all. When the key went to On, I could hear the fuel pump making what I believe is the normal fuel pump noise (kind of a light whining for about a second), but turning the key to start the engine did nothing. Lights and everything else electrical seems to be working fine. I tried jumping the truck with my Chrysler 300, running the car for about five minutes with the jumper cable connected, and revving my 300's engine here and there, but no dice.

Aside from the obvious possibilities, I wondered if the cause was related to the original issue, so I looked around online. I found out that if the starter solenoid was bad, I could jump the solenoid straight to the starter, and I should hear the starter click. I did so with an insulated screwdriver (sparks!), but no click from the starter. According to the same Advance Auto employee, that meant either the starter was bad, or there was a wiring issue. I figured, the starter looks pretty old and worn out anyway, so I'll replace it. Before I headed out to Advance Auto again, I used a battery tester I've used successfully on other cars before, which connects to the cigarette lighter. It gave a green light indicating that the battery was supplying sufficient voltage. However, that doesn't speak for cranking amps, and it's always possible that the battery tester was incorrect anyway. I suppose I could replace the old battery (after testing the current one).

I bought the starter, came home, replaced it, reconnected everything, tried to start the truck - still nothing. Tried jumping the solenoid to the new starter - nothing. OK, I probably didn't have a bad starter, but I decided to keep the new one in anyway.

So, that's where I'm at now. The truck won't crank at all.

Something I noticed was that when I jumped the solenoid to the starter, I could smell that sulfur smell (as in, sulfuric acid from the battery), and a tiny bit of smoke or mist seeped out of one corner of the battery. The terminals were previously very corroded and dirty, and I've removed them, brushed them and the posts until they were shiny, and properly reconnected them, with no noticeable difference in performance.

Another thing that boggles me, possibly involving the rough idle, is a large pipe that seems to run into the engine below the spark plugs, on the driver's side. It looks like it's been rigged and isn't stock, and it definitely isn't flush with the engine. If I watch the gap between it and the engine while the engine is running, I can see little flits of smoke along with a constant rush of air, that seem to be traveling into the engine. I've attached a couple shots of it (yep, the engine bay is dirty; I'll get to that later), in case someone can identify it. I assume it isn't the source of the vacuum leak, as a leak so big would probably not allow the engine to run at all...but I guess I could be wrong.

LBGSHI

Finally, there are three wires of concern around the starter solenoid (I've attached a shot). On this truck, the solenoid is on the passenger's side of the engine bay. One seems to be a ground, that isn't connected to anything, is red, and runs across the engine bay against the firewall, to somewhere near the driver's side cabin area (I haven't hunted it down yet, but it disappears down into the engine bay in that area). The second one of interest seems to come up from the bottom of the engine bay right next to the starter solenoid, is also red, and looks like it should be plugged into something. It's possible that it's just an extra wire for an option that this truck doesn't have; I've seen cars with extra wires because the manufacturer provides the same wiring system for all versions, whether or not all relevant devices exist in any specific version of the car. The third wire is a blue one that's connected to the starter solenoid, on the bolt closest to the front of the car. This wire is frayed pretty badly where it turns to connect to the solenoid (three or four metal strands are frayed off completely, leaving only five or six strands to connect to the solenoid), and is also worn about a foot up the wire, with the plastic corroded or burned for about an inch or so, with the metal strands exposed and rusty-looking.

Well, that's about all that comes to mind. If anyone has a clue as to any of the things in this thread, please share your knowledge. I'd really appreciate it. Thanks.

LBGSHI

I should add that I've verified that the Inertia switch has not tripped.

Also, would a bad fuel pump cause the starter to not even engage? Or would it still try to crank, but just be unable to start?

swansy

You know you have a good fuel pump because you can hear it when you yurn key on. How old does fuel filter look? That may explain rough idle

LBGSHI

I'm sure the fuel filter is old, and I'll be replacing that down the line as well. I'll definitely keep it in mind if the next few things don't do the trick, and will replace it either way, later.

tdcarter72

After looking at the 3rd pic, the wire you have labeled as "something else?" looks to be the starter wire. It needs to hook up the the solenoid on the little bolt marked with an "S". This should fix your no start problem.

If not, try grabbing the gear shifter with your left hand and holding it up in the PARK position while trying to start the truck. If this works then your gear linkage just needs to be adjusted. These model Fords are notorious for this.

Don't forget about replacing the distributor cap and rotor button while doing your tune up.

These trucks are made to run the cheap stuff. You are only hurting the motor by running the high octane in them.

This is normal.

That pipe is factory. It should go from the exhaust to the air intake tube that is going into the air filter box. It takes warm air from the motor into the air filter box and then into the throttle body until the motor warms up.


Here is one of the best tools you can buy for this truck.


Once you solve the no start problem. Pull the codes to find out what really happening with the truck instead of throwing parts and money at it. It will also help us be able to help you better.

Hope this helps

LBGSHI

After looking at various pics around the net, I was wondering if that was the case. I'll try that out ASAP.


I'd thought of that, and tried it, with no luck.


Yep; I was going to pick those up tomorrow and replace them as well, for good measure.


Ah, good to know.


Someone else said the same thing, but I wanted to verify before I wrote it off.


I was wondering if that's what it was. That makes me feel a lot more comfortable.


I've been meaning to find which code reader to order, so I didn't have to do the jumper wire/count the flashes thing. I've ordered the one you recommended, and it should be at my door Friday.

Thanks VERY much for the all the info. It's really appreciated.

tdcarter72

Here is the vacuum diagram for your truck so you can make sure that hoses are all there and connected.

Also, after re-reading your post about trying to jumping the starter at the solenoid, you need to jump from the big post with the positive battery cable on it to the little starter post marked with an "S" and NOT to the big post with the negative battery cable on it.

LBGSHI

I got home late last night, so I only spent a few minutes on the truck, but here's the update:

The starter was disconnected at the solenoid - that red wire with the boot was the starter wire. Hah. It seems like I have to have it sitting just right to make any connection at all...otherwise, turn the key, nothing.

However, even when the wire makes the connection, the starter still seems to just grind, but not catch the flywheel properly. I've got a new solenoid to replace the old one with, and I'll clean and properly seat all connections when I install it. If that doesn't fix it, I'll look at removing and reinstalling the new starter again (in case it's not seated properly), but it seems like I've installed it perfectly. I did read somewhere about a guy who had to add an extra nut to each bolt on the starter to get it to sit far enough out to catch the flywheel, but I'd imagine that's pretty rare.

If I wanted to, could I connect the positive battery terminal directly to the starter to verify that the starter is getting enough power? What gauge wire would I use? Someone mentioned using jumper cables for that, but I'm concerned that it would supply too much power and fry the starter.

I've also picked up a new distributor cap and rotor, as part of the general tune-up/attempt to fix the low idle issue.

I bought a battery load tester, so I can see actual cranking amps, power draw from the starter, etc. I'll break that out and fully test the battery later.

Are you sure that's the vacuum diagram for my truck? The fuel tanks are on the driver side, but they seem to be on the passenger side in the diagram...

kc0rey

That guy is an idiot. Ignore anything he writes.

If you choose to do this, make sure the transmission is in Park and use the Jumper Cables. Better would be to pull the starter and carry it down to the Parts House and have them test it for you.