99 SN GT40 Fuel Supply

They are flat.

The larger triangular connector is the STO connect it to Code reader. If the code reader will not communicate with ECM with single STI wire connected to code reader(no link indicator on code reader) disconnect that single STI connector and ground with jumper as the code reader manual indicates. (Page 75)

Ok, pulled out in the driveway and started it up. Ran freaking like new. No hissing, pumps primed, etc., let it warm up and then took it up to 1500rpm and then razzed it and not a missed beat.   

Tried to hookup the code reader to get some KOER readings and although little tringle showed, it wasn't reading, so while engine was running at idle, I disconnected the single grey test lead and grounded it (BECAUSE IT WASN'T READING WITH IT CONNECTED TO READER). Oh boy, the engine jumped up several hundred rpms, started hissing immediately, and died... Looked like code 08 was being displayed, so it was reading a V8. I tried to recall from memory and nothing came back..

I tried to get some KOEO readings, and again, no readings with the single wire plugged into the reader, so I grounded it, and when I did, the pumps primed. Read 11 and 10, so zip and zip. When I unplugged the ground, the pumps primed again.

What the heck? Can the single test lead be tied into shutting the pumps and other stuff off? Or is this all another coincidence to throw me off track for the 20th time??? I THINK THE CODE READER TRIGGERS THE PUMPS WHEN ENGAGED, CORRECT?

Going off to study diagrams...

Went back out to see how it would run again. Started up ok, pumps primed, and idled for a while, took it up to 1500 and then hissing started, then shortly thereafter, missing, loping, and stalled. I could not make it run long enough to get any codes while running. I hooked up KOEO, and again, 11, 10, 11. All clear..   

I tapped on the back of the ECM with key on, and PUMPS PRIME everytime, it is comical..

I am betting the house on a bad ECM and will order one on Monday from the lowest bidder!

I don't know if heat plays a role, as it runs ok for a little when it is cold, then then crappy. I can't explain why it ran well in one of the videos I posted a while back, or why it REALLY ran well today when I started it up. Took rpms great, took throttle bursts without any skipping, like were present in the video, and then just crapped out and ran bad the rest of the time. Could not get it to run like the initial 5 minutes.. The last time I had run it a few days ago before I took the ECM off, it ran like crud, so why it started up like a beast today??

Any last minute thoughts??

Oh, the code reader doesn't really work unless I have it grounded on the battery. For whatever reason, the single wire has to be off and grounding to the block or motor frame doesn't cause the square box to pop up, only ground direct to battery. I am not sure this is significant or not, but would throw it out there..

Well, the PCM Tech said that there was no test for the ECM, and you can only rule out everything else. I believe we have pretty much accomplished that.

I will order an ECM tomorrow and post results after it is installed.

I appreciate everyone's help out here. I have learned a lot more about the GT40. It has been a great running engine for 12 years, aside from a pump relay issue a couple seasons ago, I have put oil in it, new plugs, and the occasional impellor. So if I need to drop some bucks this year, I guess it will average out to be a pretty low cost over the long haul..

Weather is starting to warm up, so hope this is the fix!!

AB

Well, the ECM came in direct from PCM. It was a freaking old ECM off of some other engine, not even the 300 model that I ordered from a dealer. They sent me a 290. The case on it looked like it was dragged around on the floor vs. mine that looks basically new, so no telling how many hours were on it.

A call to the dealer and he straightened it out with PCM and I am getting a new 300 sent my way.

PCM says that Ford stopped making them so they are getting very hard to get.

My question is: Is there a repair shop that could go through all the resistors etc., on the board and determine what is wrong with it, and repair it? This thing might be worth its weight in gold some day!!

I am going to pop the new "old" ECM on tomorrow hopefully, and see if it at least runs well in the driveway.

Al was hoping all the way along it was not the ECM. You basically have to prove everything else is OK before replacing. I doubt your dealer would have been as logical in fault finding before deciding to just swap out ECM.

Just think what the dealer would have charged you to fix the problem.

There must be a business in the US that repairs auto ECMs. As the GT40 is a Ford auto based solution they use the same ECM (EEC1V) but with a slightly different "program" stored in the PROM (Programable Read Only Memory). If you can find this company send your old computer there for repair. Make sure that they send your original one back.

OK all, this has been very informative and helpful but I've got a variance of the problem going on right now.   

I do not get the hi pressure pump buzz, to make it even more interesting after working on it last week I got back to it today. Did nothing but said to myself "let's give this a try" , there it was the hi pressure pump buzz we all know and love, did it 3 times and all is good, put the water on the engine and started the engine right up.   Then about 4 minutes later motor dies and I can not get the high pressure pump to go any more.   

I have tried putting new relays, I tried the jumper suggested above, no go.   Circuit breakers look good, kill switch is in place.   I'm positive this is something easy if I can just find it.

Look forward to hearing your ideas.

Replaced the hi pressure pump,   no wonderful little hum of the hi pressure pump.   Read some more around here and thought what the hell let's play with the man overboard kill switch.   Bingo

All is good with the kill switch bypassed.   


Sidenote - threw away volt meter that showed power to hi pressure pump, when it obviously was not getting power due to the kill switch.