88 F150 straight 6 crank no start
 

Hey guys, hope this isn't a repeat but I have an 88 F150 with the 4.9 (EFI) and it wont start. When I turn the key, it will crank but not turn over. I had it running one morning to warm up and went inside. Came back out and she was off. When I turn the key, I dont hear anything coming from the fuel pump. Switching tanks at the selector does not change anything either. I know each tank has a lift pump and I have seen the external fuel pump (high pressure pump, correct?) along the frame rail. Looking for a little guidance where I should start. I tend to start reading stuff and sometimes it becomes overwhelming so just a nudge in the right direction would be a big help, thanks!

Turning over is the same as cranking - the crankshaft is what's turning over. You probably mean "firing".

Could you hear the fuel pumps before this symptom appeared? Try jumpering the DLC as this caption explains, turning the key to RUN, and then crawling under the truck to listen to the frame pump & the selected tank. Switch tanks & listen to the other:

https://www.supermotors.net/getfile/.../dlcjumper.jpg
(phone app link)

Or just use a gauge - you'll probably need it anyway:

https://www.supermotors.net/getfile/...ssuregauge.jpg
(phone app link)

If they're not running, try resetting the IFS:

https://www.supermotors.net/getfile/...itchesopen.jpg
(phone app link)

In any case, you should get a Haynes manual, and read it cover-to-cover at least once so you know what's in it & where to find what you need:

https://www.supermotors.net/getfile/...l/hayneses.jpg
(phone app link)

So I went out a little bit ago to check some things and decided to put my trickle charger on it as well, it hasnt been run for a while. While hooking up the leads, I found a wire that connects to the negative battery terminal hanging loose (someone wired in a push button start, and I'm sure that's what the wire is from). I attached it and now hear my fuel pumps. I attempted to start it and it still would not fire. I have the charger on there now, it was still cranking slowly, so hopefully once the battery is charged I'll have a different outcome. If not, back to the drawing board

Follow the link in this caption and post pics of the truck, the engine, the (heretofore) loose wire...

https://www.supermotors.net/getfile/...oorsticker.jpg
(phone app link)

I forgot to take a picture of the engine but I took a couple pictures of the wire. I pulled the #1 plug wire and, being by myself, tried the old screwdriver trick to check for spark, pic attached of my "set up" but no spark while cranking. I found an old invoice from the last time it would not start, and I had the ICM replaced. I'm laid off right now, otherwise I would have it towed and have them check it out again. Are the ICM's common failure components?

Edit: I also did check for any broken wires, as I had one break for the EEC relay and caused it to shut down and not start. I did not see anything out of the ordinary.

https://cimg0.ibsrv.net/gimg/www.f15...aa81bbe128.jpg
https://cimg2.ibsrv.net/gimg/www.f15...592a635851.jpg
https://cimg8.ibsrv.net/gimg/www.f15...e9c68b289f.jpg

The originals failed so often that there was a class-action lawsuit against Ford. But the replacements are typically more-reliable.Which wires did you check, and how exactly did you check them?

If you rely on this truck, and can't afford to throw money at it, you should invest in a Haynes manual. Click this, read the caption, & follow the link in it:

https://www.supermotors.net/getfile/...l/hayneses.jpg
(phone app link)

Read it cover-to-cover at least once - not to memorize; just so you know what's in it, and where to find things.

Those wires pinched behind the jack clamp are pretty scary-looking. Is either of them a battery feed? Are they fused somewhere? The clamp-on battery terminals are another red flag. Read this:

https://www.supermotors.net/getfile/...ail/07done.jpg
(phone app link)

I also recommend you unplug the injector blower & its control module before they catch fire.

https://www.supermotors.net/getfile/...ctorblower.jpg
(phone app link)

I more so just checked everything in plain sight to make sure there were no complete brakes or any glaringly obvious issues. That's how I had caught the relay wire before. Those wires are not fused that I know of. The red one is the one that I had to reattach (i have no clue what it is but securing it got my pumps back) and the blue goes to the positive terminal. If I'm not mistaken, I believe the blue is the power wire for the radio. Anyways, I have a daily, this is more of just a hauler/spare kind of vehicle. I just would like it to be running if/when I need it.

I dont have a whole lot of history on the vehicle, but just some background...I got it off of craigslist in 2015 and it ran. The guy did new distributor, plugs and wires before we swapped the title. The ICM was replaced in September of 2016. It's always had a hard time starting but usually runs well once it gets warm. Vacuum lines could use being redone and just an overall cleanup of the engine bay. Whoever had the truck before him wired in a push button start (ignition works to put vehicle into "on" position, the button just starts it), and they also installed a CD player.

Thank you for your input this far. I do have a Haynes manual and I am somewhat familiar with it. I did find a source online on how to test the ICM, I figure it cant hurt to cross that off, and I guess I'll check the ignition coil as well.

ICMs cannot be reliably tested; even with specialized equipment & training. The only reliable way to determine if the ICM is working or failed is by diagnosing the symptoms, using the procedure in Haynes Ch.5 (usually Sec.5 or 7 depending on edition).

Put everything you know & can find about the truck into your signature, as the caption from post #4 describes.

So the weather finally broke and I got to do some more checks on the truck today. I followed this step-by-step.... https://easyautodiagnostics.com/ford/4.9L-5.0L-5.8L/ignition-control-module-tests-1 .....and by the results of everything, it points to the ignition control module as having failed. I can hear my fuel pumps prime, theres fuel in each tank so I feel confident that this os the issue. Once I have a chance to move further, I will update with the results