Hey guys....
I'm having a problem with my truck and need some guidance as to where to go from here. I'm working on a 88 F150 with a 302 in it. 4x4, 5spd tranny. Since I bought this truck a couple of months ago, it has always started right up. I finally got around to doing some basic maintenance and now I am having a problem. I replaced the valve cover gaskets (I had to remove the upper intake), new distributor cap and rotor, and wires and plugs. after doing all of this work, my truck won't start. It is acting like it is out of time. I checked and double checked the plug wires and firing order and its all routed properly... took a plug out and grounded it and i'm getting a good spark. However, after heavy cranking, the plugs weren't very wet.... fuel pump does come on when the key is turned on. I took the line loose at the fuel filter and I had fuel that point. I checked the resistance in my coil and it seems to be ok..... I'm really not sure what to try next. How do I test the electronic module in the distributer? everything is plugged back in so, I'm guessing this is just a coincidence. Maybe I wiggled something just right. I don't know - any ideas or help would be appreciated!

 

did you pull the distributor out when working on the truck?

 

your distributor is most likely out of time !

 

No I didn't move it.... I checked to see if maybe it was loose and I didn't realize it but it was good and tight so it couldn't have moved.

 

The truck ran perfectly before I worked on it.... the distributer didn't move!

 

Is it backfiring? if so, it is out of time.

I would pull number one spark plug and then it over until you have compression and then look where the rotor is pointing, simple way to tell if you are close, then check the firing order from there.

You know it was most likely something you recently did, so start with the basics. MK

 

Try the other firing order. Someone may have put a newer engine in it.

Old=1-5-4-2-6-3-7-8
New=1-3-7-2-6-5-4-8

 

The engine has actually been replaced. I'm not sure what year motor was put in it though. I will try that... That's a good idea! Thanks!

 

Ok, so here is the deal: I tried the other firing order but had even worse results.
Next, IChecked the fuel pressure at the rail and it 40psi while i was cranking it over. I also checked the injectors and had voltage there.

Checked the compression at all the cylinders and it was good.

I replaced the coil, ignition module, stator assembly, and all plugs, wires, distributor cap, and rotor.

I also checked the wires from the ignition module to the computer connector and they were good.

Also, I positioned #1 at TDC and the rotor appeared to be in close proximity to where it should be.

Currently the truck is doing the same thing as it was yesterday. It will "start" with WOT. However, it sounds like it is running on one cylinder and stays under 1K RMP. At this juncture, Im under the impression that it has to either be my computer or it jumped time some how. Does anyone else have any other thoughts?

 

Could be the MAP sensor, there seems to be a lot of them doing this lately.
Try unplugging it and see if it will start.

But any way what codes are you getting during the KOEO self-test.

If you do not know how to run the self-test go to this link:
Fuel Injection Technical Library » How To Run a Self-Test

/

 

In one post you said you didn't move the distributor, and in the other you said you positioned it as close to #1@tdc as you could. If it has been moved, you may have to have an assistant move the distributor while it runs and kinda find something close to running, and be sure and pull the SPOUT connector while you do this. You say you replaced the ignition stator, I'm assuming you mean the pick up coil. With the exception of the pick up coil, all the other stuff either fits or doesn't and doesn't work. you could always work backwards and swap back old parts. When you did the pickup coil, everything went back together well?

 

I didn't move the distributer until today when I decided to change out all of the electronic ignition components. Yes, it was the pick up coil, the chilton manual referred to it as the stator assembly. Everything went back together with no problems. I marked everything and re-installed it exactly where it was.

 

I will try and unplug the MAP sensor. I did some research on this and the problems described are very similar to mine. I did have to unhook the vacuum line when I took off the intake. Also, I haven't run any diagnostics yet. I will try these things next and then get back to you. Thanks!

 

have you tried moving the distributor and seeing what happens ?

 

Well, this morning I went out and unhooked the MAP sensor. Same results. I then got a code reader and proceeded to check the codes. The code reader gave me code number 11 and code number 22. Code 11 indicates system pass, and code 22 indicated map sensor. I assumed this was because I unhooked the map sensor and tried to start the car. I went ahead and cleared the memory and tried to start it again. I then rechecked my codes and the only code stored was number 11. I'm officially stumped. I'm thinking my next move is to go to a junkyard get a computer and try that. Any other ideas?