Needing some help from the 5.0 gurus around here

I had something similar happen to one of my mustangs one time and it was the ignition control module on the side of the distributor
 
Swapped the old MAF and injectors back in and it fired up. Plugs are fouled badly, but at least it ran...
Unsure if the MAF is no good or if the 30# combo is too much. By the numbers, it should be the ideal amount of fuel.
I'll tinker on it later in the week and swap in another set of plugs.
 
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So you swapped to a different MAF and larger injectors but didn't change the ECU tune? I don't know how that would work properly...
 
Fabrik8 said:
So you swapped to a different MAF and larger injectors but didn't change the ECU tune? I don't know how that would work properly...
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The replacement MAF has it own calibration that in turn allows the PCM to run properly with the larger injectors.
A tune will make it more efficient, but a tune isn't needed with that size Injector.
 
Glad you got it running. Was considering plugs but it sounded like you had already swapped them. Have fun next weekend!

You are correct- injectors and the MAF need to be sized for each other. I've not messed with anything over the 19# flavor.
 
Gonna take a step back from it for a little while. I'm just too busy and working till 8 every night stinks.
Looks like Lisa's ZJ will get to hit Harlan next week.
 
I don't like it either, but I won't have time for a proper shakedown run prior to Harlan. I've done too much to it NOT make sure everything is good to go before I chunk up in Lion's Den.

I'll slum around in the ZJ and be everyone's recovery personnel, er, um, winch bitch for the weekend.
 
justjeepin86 said:
A guy I work with is a huge mustang guru, he said 30# injectors are too big for your engine.
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Yeah, I'm aware now. This engine is a solid 375-400 HP all day long and I can either run 30s or 24s but near their limit. I based that on numerous HP/Injector sizing charts online as well as advice from some racers.
Guess I know what I should have done from the start...
 
At least it was something simple as too large of injectors. Glad you didn't have to take out the engine and tear it down. Could have been worse I suppose
 
Get some 24# and cobra MAF. 24# should be plenty unless your spinning up high rpm and have high flow upper/lower intake. 24# injects can be sought all day on ebay for fairly decent prices.
 
Do you not have the ability to scale the injectors via the ECM?
 
Croatan_Kid said:
Do you not have the ability to scale the injectors via the ECM?
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The MAF was calibrated for the injectors and should have been close enough to be fine or to the dyno. My AFR gauge would have cleared that up.
It's running pretty good now with the original 24# stuff reinstalled.
However, I have a hollow sounding knock of some sort that has appeared. I'm hoping its a loose rocker or possibly a flex plate issue.
God forbid this fresh engine (that I paid stupid $$$ to have assembled) has an internal failure.
 
You change the oil since all this has happened? I'd figure the oil is definitely diluted.
 
Croatan_Kid said:
You change the oil since all this has happened? I'd figure the oil is definitely diluted.
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I'm sure that has occurred. Ill change the oil first of the week definitely. I'm going to pull the valve covers (those TFS fabbed ones won't seal for %&#@) and readjust the valves next week and do a bolt check on the converter.
Truthfully, I am burned out on it for a bit. I took the last 2 weeks off in the shop just to finish it up for April Fools at Harlan.
I'm gonna wrap up the couple of other little things it needed and go from there.
 
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