Kevin in Atlanta

Knowns:
With ignition in the start position:
Starter spins - plenty of juice
Injectors click
No spark
Fuel smell from the exhaust
No needle bump
9-10 volts at the coil with ignition on
New CPS
New front engine harness
Injector harness ends all replaced including CPS harness end
Verified continuity from computer to the CPS harness end
Swapped in new 53 for EZK relay (one with fuse tester)
12 volts go to the CE panel
11ish volts at the EZK relay - 87 and 30
Swapped computers for known good GT computers
New coils - swapped in used one same results

I always assumed for fuel to be present and injectors to click meant the CPS was ok.

Kevin in Atlanta

We also swapped the two ignition amplifiers for known good ones.

ammonman

Have you verified the fuel pump runs when cranking?

Kevin in Atlanta

We cracked the line and there is fuel.

Kevin in Atlanta

Verified wiring order on the replacement CPS harness end. Matches an 89 parked next to the GT.

GregBBRD

Did it run before the work was performed?

jetson8859

To add more details, this car hasn't ran for at least 16 years. The engine was out of the car and the bottom half had been put in an S4. There was no LH/EZK harness in the car. It literally came in about 10 boxes, and we have spent last year putting car back together. Has a Sean Ratts 14 pin harness, all engine connectors on LH/EZK harness were replaced. CE panel was gone thru and deoxit used, all fuses and relays replaced. All grounds were cleaned, and new hardware used. It also has "new" MAF.

I am leaning to something simple that we are overlooking but of my 4 928s, i have never started from ground zero without some level of known good.

worf928

buccicone

Make sure there is no relay in kickdown slot (XVII) (XVIII has a bridge connector for reverse light)

Kevin in Atlanta

Nothing and bridge, respectively.

GregBBRD

That leaves a whole bunch of possibilities, yes?

Even if the relay board is from the original car, I'd still verify the part number...the '89, '90, and '91 boards are all different.

If that is correct:
I'd start in the middle and make sure that there is 12 volts coming out of the fuel pump, LH, and EZK relays (on the "87" posts of each relay) when the engine is cranking...and move in whatever direction you need to move, from there.
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worf928

Yup.

Well, that was my Hail Mary pass. Baring the not-so-obvious-but-obvious(*), I would probably go to the basics ...

... which Greg starts with above. Those are the first steps in the LH/EZK troubleshooting matrix. That's on the Moorehouse CDs. There are a dozen-or-so specific checks for a no-start. Most of them can be done with a multimeter.

(*) the not-so-obvious-but-obvious is basically making sure you have everything plugged-in, fastened and/or connected. Visually follow all the connections from computers to injectors and plugs. Did you forget something? Engine ground strap? Coil wires to caps? Etc.

You can rule out the CPS since having injectors firing means that the CPS is sending a signal to the EZK that is sufficient for it to tell the LH to begin fueling ops..

Wisconsin Joe

No clue what is causing the issue, but you might think about yanking either the LH or fuel pump relay while trouble shooting. If you are cranking and getting fuel but no spark, you are going to wash off the cylinder walls and get fuel in the oil.

Neither are good things.

Kevin in Atlanta

We pulled the fuel pump relay once we knew we have fuel and injector pulse.

Wisconsin Joe

Glad to hear it. I tend to make 'Captain Obvious' comments.
All to often, I get a "Thanks, I didn't think of that'" in response.

Not trying to say you don't know what you are doing, but we can all miss stuff like that.