Breathing Life Into A New Lump - Need Some LT1 Help

[Fbody383]

Fighting the beast...

Car died at TWS from what I believe to be oil breakdown, i.e. it was still "running" until the bottom end siezed although the computer had cut power due to temps. I moved the intake, throttle body, MAF, etc. onto the new long block.

I have power everywhere I've checked, fuses are good and motor turns over well on the starter.

I have fuel pressure, between 40-45 depending on battery condition and no apparent loss of fuel pressure when pump is off. When cranking the engine with the fuel pump not running we see fuel pressure bleed off so I think I have injectors pulsing.

Changed the ICM because I had one but I did not have a spare coil.

Pulled the coil wire and a plug and I have spark but it appears to be weak.

Sprayed MAF cleaning into the intake directly and still no "cough."

I will pick up a new coil this evening and give that a shot. Since there seems to be fuel and timing it *should* just be lack of spark.

Is there anything obvious that I'm missing?

P.S. - Thanks to Mitch for the late evening guidance on coil/ICM.

[Wade]

Ford money is on opticrap issues.

[GlennCMC70]

I have your spare coil. I was gonna send it up to Hallett. Got swamped. Give me an address and I'll get it to you.

[Fbody383]

Ford money is on opticrap issues.

Then it wouldn't have timing to fire the coils or generate ANY spark... is that your final answer. And not that it completely matters, it is a new optispark. Maybe the SPOUT isn't hooked up right.

[y5e06]

what BRAND of opti is it? they can go bad all sorts of ways.
I put one on my Camaro that ran for 30 seconds then went totally dead. it threw an ICM code.... not the typical high res or low res opti codes. a new Delphi unit and it woke right up. at least worth the effort to run through the diagnosis.
http://www.ls1lt1.com/forum/lt1-%7C-...optispark.html
http://shbox.com/1/4th_gen_tech2.html#opti_test
factory service manual also has a good flow chart for diagnosis.

not necessarily agreeing it is the opti but, damn, i hate 'em.

[Rsmith350]

Replace the MAP sensor.

[AllZWay]

You sure you haven't messed with the security crap. Without that bypass module, my car would start and then immediately die.

[Fbody383]

Replace the coil since that was cheap-ish and easy. Good news is now a spark will jump about 1/2 and inch from coil wire.

If it was a distributor car i would swear I put the distributor in 180 degress out of phase. Before I pull the front of the motor apart I'll get an olds school timing light, pull a plug and see if the timing is close.

Morgan, thanks for the links. I did the trouble shooting and it passes - i have a timing signal and voltages in the right place.

James, good thoughts but I have the fuel pump wired direct and have never had that issue and have good spark.

Just more proof I'm a hack mechanic; updates as they happen. Thanks guys.

[Crumpacker]

Flip your tune toggle from LT to RACE or DYNO... the one labeled 'LT' is for Lemons Tech.