White Lightning troubles

[rainman49]

My trusty 1988 Ford F150 (known by the nickname in the title) is giving me trouble. A couple of weeks ago, when I would pull up to a red light the engine would rev and die. I figured the TPS was going out, but delayed any action because the problem disappeared. Then about a week ago, I cranked it up and it was running a little rough. I pulled out on the highway and it didn't want to accelerate. I managed to get it home, but the next morning it wouldn't crank. I've got spark, but the only way it'll crank is with a shot of starting fluid. Then it runs real rich. I replaced the fuel pressure regulator and throttle postion sensor to no avail. When TPS didn't do the trick, it's got me stumped. Any ideas on what to try next. I've got one of the plug-in code readers, but it won't even click like it normally does when it reads codes. Any suggestions. I'm wondering is the ECU crapped out. It's the EEC-IV.
Thanks for any help
Rainman

 

[rainman49]

Forgot to add engine specs. It's 302c.i. 2-wheel drive with 465,000 on the original engine. I've got to get WL running again so I can hit that 1/2-million mark

 

[Dark Jedi]

got a IAC on that thing? I would try that if you have one and clean it. what about the egr? I have heard ford engines gets clogged up in the tube. but dont know if that would cause a stummbling prob or no start.

 

[rainman49]

Cleaned IAC. EGR bypassed. I'm wondering if ECU has gone bad. I can crank it with starting fluid, but it's blowing a lot of unburned gas out of the exhaust. I've got an Innova code reader for it, but it won't do anything. I don't hear any clicking noises that are normally associated with it pulling codes. It's got me stumped.

 

[slickf150]

Might wanna check your feul pressure readings, pump could be on it's last legs.

 

[Dark Jedi]

if its blowing unburned gas out the tail pipe. then I would look at how good of a spark you have. also might be pumping more gas in to the chamber than it should. forget what to call it. but thats where I would look in to. sounds liek your fuel pump is pumping.

 

[The_Jeff]

injected or carbed? fueleconomy.gov says "feedback fuel system" which could be either and of course the computer could also mean either.

 

[rainman49]

It's Multi-point fuel injection. I'm leaning to the ECU (Ford calls it EEC-IV) or the ECU relay because the code reader, which usually makes the relays click, does absolutely nothing. Also, the high-pressure fuel pump, located on the frame rail runs continuously instead of cutting off after a couple of seconds. I think the ECU is supposed to have a timer to cut it off. I'll probably get a fuel pressure gauge (any suggestions on which brand) and see what kind of reading I'm getting at the Schrader valve. I pulled the ECU and there was a bit of evidence of moisture (powdery residue on aluminum) as a result of deformed rubber gasket at the firewall. Any other suggestions?

 

[Dark Jedi]

I would think you would have a lite if the ecu was going? I guess find a friend with one or goto a junkyard and get a used one and see if its the ecu. but cheaper if you could find someone with the same truck and just pop his in. if it works then you know for sure.

 

[andyd]

sounds like its running real rich. wild guess its a bum coil.

 

[Shaman]

we had an 85 with the same 302. There are a few different Spark fuel controllers that I remember. I think my father and I just started replacing the random computers that were on the thing. I had to rev it at lights to keep it alive. I don't know if it's the same problem you are having, but good luck

 

[The_Jeff]

IIRC, the ignition modules/ pickups on these things were absolutely horrible. Worse the aftermarket (wells etc) have lousy generic replacements. A ford board might help you more...

OTOH your diagnosis of a bum ECM seems logical, as the power transistors can certainly go nuts. Analog/Digital interfaces can be fragile from all the current they have to deal with even as the "core programming" works okay. And the bizzarro relay behavior kind of backs this up.

 

[rainman49]

It's alive, it's alive. All it needed was a brain transplant. After much hassle (new TPS and fuel pressure regulator)to no avail, I bought a reman ECU (which are in very limited supply) from Advance Auto for ol' White Lightning. She's on the road again, headed for that 500,000 mark. Only 35,000 more miles to go. Thanks for the input, guys.
Rainman