Sudden strange starting issue, The plot thickens Options

[emerygt350]

The past two days, cold start took longer than normal. Cranked maybe 8 times before starting. This morning it took twice that, and now all of a sudden at the grocery store after starting just fine at my office (3 block drive, engine never even got warm). It will sounds like it's going to catch but doesn't. Definitely smell gas, but not gassy. More like spark issue. I checked the wires to the coil, all seemed fine. Have not done any work on the engine for weeks. Since it happened in a busy parking lot I couldn't tell if the pump was running. Got it started, drove home 3 blocks. Starts right up again no problem.

This isn't going to be cool at Watkins glen in two weeks. I need to figure this out.

I'm thinking it's wiring to the coil. God I hope it's not the fuel pump. Next time I will have to juice it with some fluid to see if it's fueling. I don't want to put my fuel pressure gauge back in there if I don't have to.

[emerygt350]

The past two days, cold start took longer than normal. Cranked maybe 8 times before starting. This morning it took twice that, and now all of a sudden at the grocery store after starting just fine at my office (3 block drive, engine never even got warm). It will sounds like it's going to catch but doesn't. Definitely smell gas, but not gassy. More like spark issue. I checked the wires to the coil, all seemed fine. Have not done any work on the engine for weeks. Since it happened in a busy parking lot I couldn't tell if the pump was running. Got it started, drove home 3 blocks. Starts right up again no problem.

This isn't going to be cool at Watkins glen in two weeks. I need to figure this out.

I'm thinking it's wiring to the coil. God I hope it's not the fuel pump. Next time I will have to juice it with some fluid to see if it's fueling. I don't want to put my fuel pressure gauge back in there if I don't have to.

When it does start, all is good, runs great.

[GregAmy]

For fun, try jumping the fuel pump relay and see if the problem continues.

Small amount of wire, crimp on two male terminals, remove fuel pump relay and insert the jumper between 30 and 87 (diagram on the relay).

If the problem continues, and you can hear the fuel pump running, then it's not that circuit.

Note this causes the pump to stay on with the key off, so do remove it after testing. And avoid using it all the time as the pump will continue to run if you're upside down and the engine isn't running...

[Ron914]

These intermittent problems can be frustrating . Hope you get it figured out .Watkins Glen sounds like a fun weekend and the car is looking so good . With my issues I have been fighting I ended up redoing the terminals on most of the connections on the FI harness . It seemed to help but I am learning these cars are a bit finicky. I have confidence in your abilities. Good luck with it.

[emerygt350]

For fun, try jumping the fuel pump relay and see if the problem continues.

Small amount of wire, crimp on two male terminals, remove fuel pump relay and insert the jumper between 30 and 87 (diagram on the relay).

If the problem continues, and you can hear the fuel pump running, then it's not that circuit.

Note this causes the pump to stay on with the key off, so do remove it after testing. And avoid using it all the time as the pump will continue to run if you're upside down and the engine isn't running...

Definitely trying this tomorrow if it happens.

[emerygt350]

Fuel pump is working.
Put on the fuel pressure gauge and I have 30lbs like normal with the pump jumpered.
Checked spark, a little weak but not awful.
Checked it at the coil and pulled a plug and verified spark at the plug.
Tps causes injectors to fire.
Disconnected TPS same crank but no start
Replaced ecu with my other known good and no change
Cleaned all grounds at the back.
Cleaned all relay and sockets on the relay board
Verified voltage at the coil (drops to 9.5 when cranking)
Replaced coil with known good original Bosch, no change
Cleaned rotor and dizzy
Only once did it fire at all during all my cranking this morning.

I really think this has all the feels of a loose wire.
Something that might make the injectors not fire?
I checked the wires to the 123 dizzy but all looks good.

[Superhawk996]

CHT and grounds for the injectors are prime suspects.

Don’t you have some Bluetooth variable resistance stuff wired into the CHT circuit? Verify the integrity of anything that’s modified.

No mention of having tried starting fluid to confirm you have a fueling problem.

[emerygt350]

CHT and grounds for the injectors are prime suspects.

Don’t you have some Bluetooth variable resistance stuff wired into the CHT circuit? Verify the integrity of anything that’s modified.

No mention of having tried starting fluid to confirm you have a fueling problem.

All of my crazy is out of the cht circuit. I will have to double check the connections at the resistor.

Couldn't make it to the store for starter fluid. That will have to wait for tomorrow.

[Lockwodo]

The 123 ignition provides the trigger pulse to the injectors, have you verified that connector is tight?