7.4 454 won't start

[Isaabalot]

I have a 94 winnebego motorhome with a chevy 454 TBI ECM 16196395 PCM. I drove it up to my house and it ran fine. Then later in the day I went to start it and it cranks but won't start. I popped the engine cover off and I can see the injectors are not firing. I sprayed carb cleaner in the throttle body and I can get it to start.

I found the pinouts for the different ecm that says it works 16197427 on this forum. I checked for power and ground on all wires I could identify with power or ignition. I checked all fuses and pulled fuse box out and checked all connections behind with a power probe. (History of poor connection at ecm fuse).
I cracked the fuel line loose and turned the key to on. Fuel does spray out. (updated: checked f15, e15 ignition feeds, e16 battery, a1, a2, b4, b3 grounds all good.)

I bought a new ignition control module since it was cheap, no change.
I still have spark. No fuel injectors. I verified power at the supply wires on the injectors. I do have constant power.

I replaced the ECM because it was cheap and swapped the prom over. I was told by one of those online help justanswersrv the ecm was probably bad/injector driver failed.

I'm at a loss where to test next. I don't know what order to test anything else in. I'm wondering if I should try a pinout of the 16196395 ecm since I just found it. But I believe it is the same.

Please help! It is a 34foot motorhome blocking the driveway. lol

[Isaabalot]

Ok so I went through the proper pinouts for 16196395 like I had suggested. I looked at every pin that I could guess would effect starting.
E15, F15 are ignition and they do come on.
E16 is battery and it has power.
A1, A2 are ground and have no resistance to ground.
B4 map ground is good.
B3 Ect ground is good.

F6 says fuel relay control. I am assuming it grounds the low current side on the relay when triggered? Not sure how to test this.
B12 fuel pump signal. Not sure how to test this.
A16 Injector control 1. I assume it pulses ground to the injector 1.
A9 Injector control 2. Also assume it pulses ground to injector 2. Is there a way to test this?
F11 IC signal from ignition control module.

So I'm still at a loss but not giving up. Would I still have spark if the pickup coil was NOT working?

[tayto]

wasn't this exact issue just posted like a week ago?

[tayto]

http://www.gearhead-efi.com/Fuel-Inj...-1500-no-start

[dave w]

I wonder what a NOID light test would show?

dave w

[ralmo94]

I wonder what a NOID light test would show?

dave w

He might need more help, as to what you want him to put the NOID light on.

If you have spark, and can start with priming the TB with fuel or starter fluid as you said, I would look somewhere besides the distributor.

Pinout should be the same between 6395 and 7427.

If you have the dog house in an RV that you can watch the TBI from the driver's seat, I would test to see if you get the key on prime pulse. When keyed on injectors should fire a priming pulse. You should be able to hear them if you listen, and should be able to see fuel squirt.
If I remember correctly, the fuel pump relay is only used during cranking, and PCM takes over after that. You could jumper the relay to verify you hear the fuel pump running, might require a helper with a 30+ft RV

Without being hands on, that's the best I'm able to offer hope it helps. I would suspect a connection somewhere.

Sometimes trouble shooting is the hardest part.