Recently I parked my car for 3 days in weather where the high temp was 30* and barometer and dew point where through the roof. Since I put this engine in I have never had a problem starting or driving it in any weather, till now. simply put the engine will not start. Heres where I am:

Optima has a solid 11.5-12.5 volts while cranking and around 13 when sitting.
Starter engages and turns engine over easily
All Fuses and relays are good, all electrical systems work.
Noid light flashes which shows both banks of injectors are getting signal
fuel Pump comes on and Fuel pump relay clicks.
Fuel Pressure shows a constant 42 psi while cranking and priming
Spark Plugs are sparking (I pulled a few to be positive)
Replaced Ignition control module- still no start.
Removed air intake assembly and filters- no start
Checked all sensors via Tuner Pro RT v4-all had normal KOIO values.
MAP sensor changes when vacuum is applied.
Swapped out ecms, proms, chips and adapters- no start.
Saw no obvious cut wires or loose hoses.
Engine is a MAP based system with no emissions or cold start injector.

I am leaning towards the magnetic pick up coil or distributor. I noticed a small amount of play in the distributor and I was not recieving an injector reference pulse or spark advance value while cranking. Could it also be that the ignition coil is becoming weak and not energizing every time? It is a MSD that is 3 years old.

Any suggestions are appreciated.

 

Use a Spray bottle to spray fuel into the TB, if it starts, it's an ignition problem.

Post your findings.

 

Being TPI with long runners thats a little bit tricky. I sprayed starting fluid into the TB before and during cranking and still had no start.

 

I believe he meant to tell you that if it started than it was a fuel problem. With no start at all there is only two other options. Loss of spark...does it sputter or even react to the fuel being added?.....Or Compression, If you have a compression tester now is the time to use it.

If nothing happens at all when you sprayed fuel into the TB than it is definetely Compression or Spark problems. I would just replace the cap and rotor and have the new ignition module tested. It wouldnt be the first time I saw a brand new faulty Ignition module.

Hope this helps

 

I went to replace the whole distributor last night, thought I would try starting it before I changed it though. It started right up. So I came out every hour last night to try starting it and it started up every time. Drove it around with no problems. Which makes me believe that whatever the problem is will be back. Could it be possible that there was a small amount of condensation under the cap or trapped somwhere?

 

This brings back an odd occurance. I believe it was my '76 Camaro Z28. The engine would not start,,, the weather had gotten colder,,, if I cranked it alot, over & over, it would finally start. It was a break in a wire (I believe) in the coil, the little bit of extra warmth from constant cranking closed the gap, and the engine started. Replacing the dizzy elimenated the problem.

 

You said a brake in the coil, meaning ignition coil? So did you have the HEI cap in coil dizzy and replace the whol thing? please clarify.

 

It was a coil in the cap type dizzy, so I must have just replaced the cap,,, but I dont remember exactly, sorry, its been quite a while. And, it could have been my '84 z28, not the '78....But it was a break in a wire in the coil, or a separation in a connector inside the coil. Replacing the coil (or entire cap) fixed the issue.