We have combed through forums for hours, we are at the end of what we can come up so any help is appreciated; but here's what we did.
Truck: 1993 K3500 454 TBI Automatic Trans
(Recently purchased from the third owner and have been doing updates, upgrades and improvements to get it to where we want to).
Bottom line up front: crank, spark, fuel, no alternating injector pulses during cranking.
Head gasket leak led to an overheat and it busted open the plastic side tank cooler of the radiator. It DID run afterwards as we had to move it around the yard and into he garage (briefly where it didn't get up to operating temp).
We figured out it was the head gasket so we pulled the heads, had them resurfaced and manually ported them nicely (enough) with a die grinder.
Replaced the radiator, and some other accessory parts.
Got everything buttoned up together. Cranked, spark, no fuel.
Turns out we were just low on fuel. Added 5 gallons, still no start.
We realize we weren't getting the alternating injector pulse when cranking but we get the initial shot when we turn the key to on.
Utilized injector light testers, no alternating light flashes. Replaced the oil pressure switch, no change in results.
So after we tested and checked grounds, we replaced the ICM on the distributor.
At one point we got very rapid and random firings of the injectors while NOT cranking.
Replaced the PCM utilizing the same PROM with jet performance chip. Replace the ICM with another one!
For the first time we cranked, saw alternating firing of injectors and paused to button everything up to hopefully fire off.
No dice....
We've tested continuity from the TPS, ICM, etc from there to the PCM(ECM). Utilized dielectric grease, checked connections, and yes of course we've checked fuses and the fuel relay. We have even hot wired the fuel pump to ensure the pump is running with it cranking.
Are we to believe the PROM is bad or fried from a short?
Thanks! (Please HALP)
Truck: 1993 K3500 454 TBI Automatic Trans
(Recently purchased from the third owner and have been doing updates, upgrades and improvements to get it to where we want to).
Bottom line up front: crank, spark, fuel, no alternating injector pulses during cranking.
Head gasket leak led to an overheat and it busted open the plastic side tank cooler of the radiator. It DID run afterwards as we had to move it around the yard and into he garage (briefly where it didn't get up to operating temp).
We figured out it was the head gasket so we pulled the heads, had them resurfaced and manually ported them nicely (enough) with a die grinder.
Replaced the radiator, and some other accessory parts.
Got everything buttoned up together. Cranked, spark, no fuel.
Turns out we were just low on fuel. Added 5 gallons, still no start.
We realize we weren't getting the alternating injector pulse when cranking but we get the initial shot when we turn the key to on.
Utilized injector light testers, no alternating light flashes. Replaced the oil pressure switch, no change in results.
So after we tested and checked grounds, we replaced the ICM on the distributor.
At one point we got very rapid and random firings of the injectors while NOT cranking.
Replaced the PCM utilizing the same PROM with jet performance chip. Replace the ICM with another one!
For the first time we cranked, saw alternating firing of injectors and paused to button everything up to hopefully fire off.
No dice....
We've tested continuity from the TPS, ICM, etc from there to the PCM(ECM). Utilized dielectric grease, checked connections, and yes of course we've checked fuses and the fuel relay. We have even hot wired the fuel pump to ensure the pump is running with it cranking.
Are we to believe the PROM is bad or fried from a short?
Thanks! (Please HALP)
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