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I have a 1988 F-150 5 speed with 4.9 inline 6. Can anyone tell me what this plug is for? I have a feeling it is the reason I am not getting an injector pulse. It is near the brake booster and master cylinder. My EEC and Fuel Pump relay circuits are working, I have fuel(50psi) and spark(test light at coil) but the noid light on the injector will not come on. I do have 12v at the injectors.
That plugs into the flux capacitor. If not plugged up properly, a rip in the space/time fabric will occur and we will all be sucked from the galaxy by a vacuum leak greater than the one found on my truck earlier this year...
Hard to say with that view, based solely on that like my fellow poster above..... I got nothing.
Need to know the color of the wires to it, all of them. Then it should be fairly easy to narrow it down.
However unless something has been changed, a motor swap and was missed or components removed to clear way to repair something else in the process, likely its just for something your truck doesn't have and never did.
Yes, there was an engine swap made. The engine originally in this truck had a blown head gasket and a cracked front exhaust manifold, so I replaced it with a good engine from an 86. I swapped over all of the EFI stuff and got rid of the emissions equipment, leaving the TPS,MAP sensor and the IAC. Was going to megasquirt it and run direct coil control, but because of unfortunate circumstances my project truck has become my daily driver and I need it ASAP.
The wires running into the first plug are as follows:
Brown |White/Pink or Red Stripe(Lots of grease)
Yel/Brn Stripe |Grey/Black Stripe
Black/Blu Stripe |White or Yellow(Lots of grease)
I hooked up everything that I could and was left with that plug and a few others, which will be pictured below. I believe that they are just for a resistor or capacitor of some sort according to my Haynes book. They are both a part of the same harness that run to the dizzy and the coil. Maybe someone can confirm what these are.
Last edited by kyle.quamme; Dec 19, 2010 at 08:47 PM.
Reason: spelling and detail
For some reason I'm just not seeing anything matching that color code in the diagram I have.
Having a brown in with the mix suggests a lighting circuit but find nothing that route either, thought maybe trailer brake controller but its location nor color code match it either. Doesn't match the injector blower relay socket either, at least not in my book,
As for it not firing the injectors, do you have the smaller computer ground cable connected to the negative battery post, a "black-light green" wire?
The other two connectors, hard to say with the fuzzy picture but the flat one kinda looks like for a A/C compressor clutch. Wire color code might help narrow it down.
The other roundish one, can't say going solely by the picture but posting its wire colors might help with it too. Can't quite make it out in the picture
the flat connector is for the a/c clutch, the round one looks like the spout connector for the dizzy. ill look at my truck in the morning to verify the round one
Thanks for the info. I got rid of the A/C so no need to worry about that one. The other one still has me for loops. If it is indeed for spout, what do I connect it with?
I have wired the green/black stripe wire to the ground on the battery.
Ok guys. I think this is the spout that everyone is talking about.
This is the original connector I posted, at another angle. One green wire, one black wire. Looks kinda like the one for the coolant temp sensor but that is with the harness for the injectors afaik.
With that slide on the back I would suspect that it's the rear abs testing port. Hooks to the driver's side bracket where the EEC-IV port is located but closer to the outside of the truck.
I think the connector in the very first post normally goes to the cruise control vacuum servo. The round connector with the green and black wire has me stumped if it's not for the coolant temp sensor. My other thought was canister purge valve, but it's in the wrong place for that too...
I think the connector in the very first post normally goes to the cruise control vacuum servo. The round connector with the green and black wire has me stumped if it's not for the coolant temp sensor. My other thought was canister purge valve, but it's in the wrong place for that too...
The first part would make sense because of its location on the firewall next to the brake booster. My truck doesn't have cruise, so it's probably just there for no reason.
After finding more diagrams and pictures, I discovered that the plug that looks like a coolant temp sensor plug is for a knock sensor, which this block does not have.
Last edited by kyle.quamme; Dec 20, 2010 at 08:42 AM.
Reason: New Info
The jumper in your first picture post #8 yea that's the spout.
Second picture, I couldn't help notice while changing the sector shaft seal (yet again) on my 94 that it has that same connector up by the brake booster.
I'm thinking its for the engine compartment light, my 94 doesn't have one. The color code is just about right, book says Black/Green-yellow. I didn't look real close it may have a small yellow stripe on the green wire?
The very first connector, I looked at the cruise servo while it doesn't match the diagram I agree its the most likely candidate.
I have wired the green/black stripe wire to the ground on the battery.
Was connected? or you connected it and now it fires the injectors?
Did you run the self test, see if the computer can tell you anything.
Pull the spout jumper out, test see if it fires the injectors without it in place.
If no help test/check the TPS. Back probe the connector, test ground and signal wires, should read 0.50 to 1.0V key on engine not running with the throttle plate fully closed, if you get 4.0 to 5.0volts for some reason, say the TPS installed incorrectly for example, that's likely going to be the problem.