I'm starting to hate my truck!

[alwaysFlOoReD]

I've been working on my race truck [91 4.0l/5-spd] for the last few days. I installed some new rear shocks and new shock mounts, and fixed the rear fender mounts and rear bumper. Absolutly nothing to do with electrical. I did some welding but disconnected the battery. I have no spark. It looks like I have some fuel but don't know exact pressure, some fuel came out of the fuel rail when I depressed the schrader valve. My fuel tank is full. My fuel pumps come on when I switch on the trucks master disconnect switch. I read some posts on TRS about no start situations.
I decide to go with the easiest to acces first;
-There is 12v at the red wire at the coil pack.
-I swapped out the coil pack from a known running truck - no change.
-I swapped out the edis6 module from the same running truck - no change.
-If I understand correctly there needs to be an AC pulse from the crank position sensor. I checked as best as I know how and came up with no reading on my multi-meter. It is auto-ranging and figures out ac from dc on it's own so pretty much me-proof, lol. I changed out the cps with a known good one and no change. Did another multi-meter test and still no pulse registering with this cps either. I hooked the leads directly to the cps and cranked the engine.
-The relays seem to be good, I swapped out the green and the brown, but didn't have a black one.

Tomorrow I will r+r the cpu from the running truck, a 94 4.0l/5spd, as long as the cpu will interchange. I had to look mup where it's located tonight or I would have done that already.

Soooo, is there something simple I missed? Any help appreciated as I need this running for this weekends races.

Thanks,
Richard

 

[RonD]

The CKP sensor, EDIS module and coil pack makes an autonomous system, doesn't need computer to work, computer helps spark timing for better performance and emissions but many used EDIS as a stand alone system.

And it is super reliable, so yes probably something simple being over looked.

CKP sensor is a variable reluctance sensor(VRS), and it will generate about or just under 1v AC using starter motor.
These rarely fail on Fords.

EEC relay(brown base) powers these parts along with EEC, but also fuel pump relay, so if you hear the fuel pump come on with the key then EEC relay is closing.
But wire under it can get corroded.

This site has pin out for EDIS-6: http://www.dainst.com/info/edis/edis.html
might check it for 12v, also good place to test for AC from CKP sensor, but real long shot that would be the problem.

Have you tried just putting gas or starting fluid in the intake to start it, simple test to determine spark or fuel problem.

 

[alwaysFlOoReD]

IIRC, I have the fuel pumps wired directly to the master disconnect. So no relay involved.

I will check with starting fluid tommorrow, I pulled a plug after cranking and didn't see signs of gas...good point.

I found that link on another post you made and did check for ckp signal and didn't get any. Perhaps I was counting pins from the wrong end. I will double check tomorrow.

Thanks.

 

[alwaysFlOoReD]

Sprayed in some starter fluid and it fired right up. I don't know why I didn't see spark before. Thanks for the suggestions.

Sent from my XT1032

 

[Mark_88]

That may or may not indicate a fuel problem...had the same thing happen to my Tempo once (only once) and after fooling around with it for an hour tried spraying starter fluid and it fired right up also...never had a problem after that and didn't need to fix anything else...however...

That was when I discovered that little rubber boot that Ford put on the distributor...keeps the dampness off and helps starting...I think the coils need something like that but they may get too hot...so...anyway...if you haven't already done so might be a good time to check the fuel pressure...

You will probably forget so I am reminding you in advance to keep an eye on that...

 

[alwaysFlOoReD]

Thanks.

Sent from my XT1032

 

[bobbywalter]

sounds like your fried the ground for the ecm or the internal ecm ground....



find the ecm ground and make sure its continuous to the ecm from the battery. that and the relays are strobing correctly. is the fuel pump running the whole time the power is on? or does the ecm control it? if the ecm controls it and its not cycling with key on then the ecm has an issue. theres several fails that can happen when welding.

 

[alwaysFlOoReD]

I'll check the grounds, thanks.
The fuel pumps are not controled by the ecm.

 

[Big Jim M]

When welding on a vehicle always clamp the ground to the PART you are welding! So the return is direct and not thru the grounds built into the vehicle. Them vehicle grounds will go away real quick.
Big Jim

 

[alwaysFlOoReD]

Yes, thanks. It bears repeating, the shortest path to ground is the best....especially when standing in a tub, lol.

Sent from my XT1032

 

[RonD]

Yes, thanks. It bears repeating, the shortest path to ground is the best....especially when standing in a tub, lol.

Sent from my XT1032

I always thought the wife did it, but she was cleared when she said, "he always made toast while taking a bath, our toaster was always kept in the bathroom"

 

[alwaysFlOoReD]

Update;
I pulled the after market low pressure pump to use on my f-250 and found it wasn't working. This may have been the problem. I've heard that as long as there is fuel at the high pressure pump it will suck from the tank via siphon. I plan on putting in a hand operated siphon as used on portable marine tanks and see how that works. $15.00 versus $80.00 [low pressure pump].

 

[bobbywalter]

fawk that low psi pump.....just run a line there and make a nipplator for the sock....or run sockless if you dare

 

[Mark_88]

Update;
I pulled the after market low pressure pump to use on my f-250 and found it wasn't working. This may have been the problem. I've heard that as long as there is fuel at the high pressure pump it will suck from the tank via siphon. I plan on putting in a hand operated siphon as used on portable marine tanks and see how that works. $15.00 versus $80.00 [low pressure pump].

It should work, but...do you really want to put that kind of strain on the high pressure pump? I was running a low pressure pump on my carbed setup for the last ten years or so after I replaced the 2.3 block. It was fuel injected and didn't have the hole in the block for the manual pump so...electric low pressure mounted under the hood...

That was quite a distance for the pump but with the right setup in the tank it works just fine...like Bobby said...see if you can remove any restrictions on the pump in the tank and it will pull the fuel easier...even setting up a small low pressure pump outside the tank would work...although I recall there being other lines that may complicate that process...

fawk that low psi pump.....just run a line there and make a nipplator for the sock....or run sockless if you dare

This gets a bit of my brain working in a direction I don't want to go...lol

 

[alwaysFlOoReD]

fawk that low psi pump.....just run a line there and make a nipplator for the sock....or run sockless if you dare

This is what I'll try first.

It should work, but...do you really want to put that kind of strain on the high pressure pump? I was running a low pressure pump on my carbed setup for the last ten years or so after I replaced the 2.3 block. It was fuel injected and didn't have the hole in the block for the manual pump so...electric low pressure mounted under the hood...

That was quite a distance for the pump but with the right setup in the tank it works just fine...like Bobby said...see if you can remove any restrictions on the pump in the tank and it will pull the fuel easier...even setting up a small low pressure pump outside the tank would work...although I recall there being other lines that may complicate that process...

The aftermarket low pressure pump was outside the tank. The tank is a fuel cell with no option for intank pumps. There is outlets at the top of the tank but not elsewhere. I decided to use a low pressure pump when I built this truck because I was concerned about over-taxing the high pressure inline pump [unlike our governments concern about taxation].
The setup was;
Fuel cell> filter> low pressure pump> filter> accumulator> high pressure pump> filter> fuel rail

Why so many filters?...I was using as many factory lines as I could and used them for male to male adapters. Uh Oh, this seems to tie back in with Bob's post.....

This gets a bit of my brain working in a direction I don't want to go...lol

Me too!