Dang SC, now I have fuel but no spark

Scott Long

Registered User
I just rewired my fuel pump tonight with 10 ga. wire and a 50 amp switch. I flip the switch, pump comes on and I hear fuel flowing through the lines under the hood. I go to crank the car and it just cranks and cranks. I pull a wire off the coil pack and crank it, but no arc. So now I have no spark.

I think the IRCM may be the culprit. The IRCM runs the ignition, injectors, and fuel pump correct? My fuel pump and spark went away at the same time. I put in a new pump, and now rewired it. But there is no spark.

However, when cranking the upshift light stays on. This would usually mean crankshaft position sensor, but since I lost the fuel at the same time, I think it's the IRCM.

In August of this year I changed the DIS, cam sensor, and crank sensor with brand NEW parts. So I doubt the crank sensor is bad in 2 months time. However the IRCM is 17 years old.

Are all IRCM's interchangeable? Or do I need one from an early year auto?

Where can you get one new or aftermarket or am I stuck buying used?

Anyone want to send me one to try out to see if it's the problem?
 
wow..I can't remember the wiring but I know there a couple safety interfaces tying fuel pump running to ignition. It is possible if whatever is supposed to energize stuff for the pump is tied to the EEC regarding ignition.

I'll check around.
 
Scott,

alldata has a large section of pinpoint tests for the fuel pump circuit. Some images available below.
 

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I can elminate a ton of those trouble shoot things.

I'm wondering if it's possible the IRCM died itself. Because I find it odd a crank sensor and fuel pump die at the same time. Especially when the crank sensor is only 2 months old, but the car isn't even a daily driver anymore.
 
Look to see if you have 12v at pin 24 of the IRCM with the key on. ZThat is the EEC relay circuit that supplies 12v to the PCM, the fuel pump (through the FP relay, and most actuator or output devices controlled by EEC.

If you have 12v there, the problem is somewhere down the line, either a short to ground or open before all those things that aren't working. No 12v there and the IRCM, specifically the EEC relay is most likely at fault. It prolly wouldn't hurt to check what pin at the IRCM gets power from the IGN switch and check for 12v there also.
 
The ignition switch is less than a year old and the brakes, heater, etc... work. When it was bad last time the brakes and heater would shut off intermittently.

I think the EEC might not be getting power. But the CHECK ENGINE light and up shift light come on with the key and the upshift, check engine, and check gage light stay on while cranking. The check gage light is on because the oil pressure won't register until the car is running. But the upshift light has me worried. I pulled the IRCM out and unplugged it, tried to crank it and the same thing. The upshift light and check engine light are on while cranking even with no IRCM.

Makes me think the IRCM is bad. I am going to try and find another one.
 
Which year SC are you working on? The 89-90's had one version of the IRCM and the 91-93 had a different version. Neither versions had a Fuel Pump Relay like the later years did BUT the ECA Power Relay did power the remote fuel pump relay itself.

Stupid question....have you checked all your fuses yet?
 
I didn't say anything about the switch itself. I was indicating to verify the IRCM is getting the 12v from the ignition when it's turned on. If you don't all the IRCMs in the world aren't gonna make a diff!

Pin 13 at the IRCM is 12v from the ignition switch. Also, pins 3,4 & 8 should be getting 12v too.
 
I didn't get to check pin 13 yet, but I will if I can find my voltmeter.

I found another IRCM and the part number is the same as mine: E9SF-12B577-AB

However the one I can buy is from a 91 Auto, mine is a 90 Auto. I have already re-wired the fan on a relay and seperate of the IRCM. Would this one not work on my car since it's from a 91 and mine is a 90 even though the part numbers are identical?

The one I can buy has a sticker on it from 2000 so I believe it's a newer motorcraft unit. This is 10 years newer than mine.

Duffy: Yes I checked the fuse for the EEC in the box underhood and even swapped it with another 30 amp with the same result, no spark.
 
Functionally concerning fans and EEC you are correct DeepblueSC but please don't leave the impression that the 89-90 versions of the IRCM are interchangeable with the 91-93's in all regards. You coud very easily have someone purchase an E9SZ 89-90 version for a 91, 92 or 93 and then wonder why his/her Electronic Climate Control does not work properly or his/her fuel pump won't run either.
 
Well even though it's currently on a 91 that is being parted, is the E9SZ part number that's identical to my part number interchangeable?
 
So does the CCRM, or ICRM or whatever have anything to do with fuel pump running? The diagrams I look at all seem to indicate no. That is assuming the ECM has power, which does come from the relay unit.

I don't see anything related to fuel pump lack of operation that would stop the EEC from lighting up the spark plugs.

good luck chuc...uh, scott.
 
Depends on what year model you are talking about Mike concerning the fuel pump. ALL SC EEC's I know of have a feature that shuts down the fuel pump after like 3 sec.of no start cranking. It is done to stop from flodding the engine. Some IRCM's have functionality of a fuel pump relay inside...some just route power to the coil side of the fuel pump relay. Some have nothing to do with the fuel pump circuitry directly. But all SC IRCM I know of supply VPWR to the EEC via the IRCM ECA Relay so if no power to the EEC....NO SPARK.
 
Hopefully by me hotwiring the fuel pump the EEC won't know the difference.

If the Check Engine light is coming on, I thought that meant the EEC had power. But when I removed the IRCM and turned the key on, the same lights that always come on, came on.

All I know is I have no spark. If I have to rewire the EEC..... so be it. I'll try an IRCM first, then maybe a crank sensor again. And if that fails I'll have to find out what isn't getting power to run the ignition, and then make sure it's getting power. I highly doubt it's a wiring problem though because my car has never had or currently have any electrical problems.
 
hey scott what you need ill ship you every part i have try it if it cures the problem send back what you dont need you pay shiping both ways part is free i have ircm eec coil pack dis you name it i have it exept crank sensor thats sold . make a list.
 
Ok Manny, as we discussed I will need an IRCM to try and see if maybe the EEC relay in mine was bad. I just put a crank sensor on this car in August, so I should be able to get another one under warranty if it's bad. The only reason I thought it may be bad is the upshift light. But since the fuel pump died and there is also no spark, that leads me to believe it's something else.

What is the possibility of the EEC itself dying? Would I need one from an Auto or did the early years not differentiate between manual and auto?

Let me know what you need to ship it. If the IRCM doesn't fix it I'll be swapping EEC's next.

I need to go find my voltmeter but somehow I think it didn't get moved down here with my tool chest. I still have a lot of tools in Michigan.
 
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