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Discussion Starter #1
OK, '87, 302EFI, AOD. I changed the p/s gearbox seal and changed the oil last saturday, and parked it across the street. Went to go wheeling last sunday, and it wont start. It cranks over fine, but will not light off and run.

-I've got spark-laid a plug on the intake and cranked it over.
-It's got 38psi of fuel pressure
-Checked timing; TDC on #1, and the rotor is pointing at #1 on the cap
-It's got 120psi cyl. pressure
-Only 2 codes coming out of it are 31, and 52.
- 31; EGR has been bad for almost a year now, no light, no problems
- 52; p/s psi switch had been disconnected since saginaw went in. Again, no light and no problems.
-The red "ENGINE" light has been on constantly since I installed the auto meter oil pressure gauge and disconnected the factory one. This has only been since new years, and it has run fine since then.

Its obviously getting fuel, becuase I can smell it while cranking, and the plugs are soaked with it when I pull them out.
I'm missing something here, but its apprently beyond my abilities. Any other ideas/help/wild shots in the dark are appreciated.
 

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Ex Navy Nuke
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5,420 Posts
Spark, fuel, air, compression, timing. Sounds like you have them all but obviously at least one isn't enough. Probably a weak coil. All you can really test on the coil is resistance. If it tells you it's bad then it's definitely bad but even if it tests OK it might be bad. Try putting a timing light on it and seeing what the timing is while having someone else turn the engine over. If the timing is fine then I'd replace the coil.
 

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Pretty much. It is possible that your ign. module has gone tits up from the MSD coil. However, just for S's and G's, try the original coil if you still have it. Could still be your coil. I will always suspect the modified part, just my .02
 

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Ex Navy Nuke
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If you have access, try your coil on another vehicle or someone else's "known good" coil on yours. Check the timing like I said earlier also while cranking. If timing and coil are good have the TFI module tested.
 

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Discussion Starter #8
Well, its not the coil. Swapped it out for one that I know works, and nothing different. oing to check the timing while cranking now; but not sure what it should be?
Is there any way to test the TFI here, or do I have to take it in? (my manuals are at home, but I'll be retrieving them soon)
 

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Ex Navy Nuke
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I think there is a test procedure for the TFI module but it's better to take it to a parts store and have them test it. They will run it a few times to allow it to heat up. Many times they will test out ok when cold but show bad when they get hot.
 

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Discussion Starter #12
O'reilly's checked out the TFI. and warrantied it out. I had put one in 2yrs ago. Put it in, and no change. Pulled #1 plug out, and its still getting a bright white flame, and can still smell the gas going in.
DAMMIT, it should run! It's all there, why is it resisting me???:banghead :banghead :banghead
me:twak fuel injection

Someone help, please.
 

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Appy-

I know you're frustrated to defcon 5. Is there any restriction on the intake side restricting air to the throttle body? One of my service trucks with a 351
was not able to breathe because the driver never ever serviced the air filter.
Symptoms were similar to yours. After servicing the air box, replacing the filter, and cleaning the TB, the truck fired up and ran like crap for about 5-10 minutes, then leveled out and ran fine.
 

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strange suggestion, but it's worked for me in the past: Pull the positive cable on the battery for 10 minutes, clear out the computer.

Also, your initial post said the timing was set to TDC? Did you mean 10 degrees BTDC?
 

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Discussion Starter #16
sewiv said:
strange suggestion, but it's worked for me in the past: Pull the positive cable on the battery for 10 minutes, clear out the computer.

Also, your initial post said the timing was set to TDC? Did you mean 10 degrees BTDC?
I've cleared it twice now, with no luck.
I meant that the rotor is in the correct position at TDC. It's set at 15 or 20* advanced, can't remember.
 

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when its cranking does it sputter or pop at all?

Any sign of life or is it just cranking like you had the coil unplugged?
 

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Discussion Starter #19
I've got the MSD coil, motorsport wires, and plugs at .055". And no, it doesn't do squat but spin around. If I hold it to the floor, it almost tries, but still won't go under its own power. I laid one of the plugs on the manifold today and watched it spark away while I was cranking. It's just the weirdest damn thing I've ever seen.
 

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my 351w is doing the same thing right now...
only mine the 351 Firing order it pops and sputters but wont kick...and 302 firing order it fires right up but has no power under load...

check your compression again
check spark on another plug, pull a plug and have someone crank it...watch for fuel to rule out injectors
check fuel pressure again
sounds like a sprak issue...either no spark or no fuel...if its got spark and fuel it will make fire
good luck

dc
 
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