92 Ram. Im begging for good mechanic advice...please

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I'd really look hard at the fuel pump module. Sounds like the pump is dying.

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92 Ram used an SBEC controller. ECT is on a dual range scale. At cold start it has a 4.75 - 1.25 volt range. At approx 125 degrees F, the ECT volts should have dropped to 1.25v. At this voltage the SBEC internally adds a resistor and the ECT volts JUMP UP to approx. 3.75 and then again use the 5v scale downward as the engines continues to heat up. Verify that this transition is happening at approx 125 degrees then MOVE on............

Good luck

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I have a 92 5.2 Dakota that had the same symptoms. Had to replace the black box on the fender under the hood. SBEC controller?? Anyway. after we replaced it I never had another problem

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We previously gave the truck a tune up. New plugs, wires, cap, rotor, cleaned the throttle body, checked the wiring and connections. Looking for loose or non grounded items. Without using a wire testor hard to tell if there are any wire breaks under the wire wrap. We have changed the coolant temp sensor, ait temp sensor and Map sensor. No codes from the computer. I have thought about the intake and or head gaskets, because the dealer once said he noticed a puff of smoke during start up. I have not actually seen this, but why would he make it up. I also thought about valve seals. But again, why only when it is cold? During the summer months it drives great. I am trying to keep the truck around because it is paid for and otherwise, nice to have for hauling. I am just finishing up my garage project and am anxious to finally get back to working on my muscle cars which have been sitting for 10 years, so I don't want to spend all my free time or money on this truck. So I am stuck because the dealer can't seem to find it without breaking my bank and the issue seems complex and above my previous attempts. But someone has to know.

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Do yourself a favor and actually test the fuel pressure with a guage. Knowing what the actual pressure reading is the correct way to diagnose the problem. To little pressure as well as to much fuel pressure will both cause a host of problems.

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Also check your steel fuel line from the tank for rust. You may not see/smell anything, but a tiny pin-hole will defeat your pump. DAMHIK...

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Is that a tbi? I had a 90 tbi equipped ramcharger with a bad sbec (computer) that would die when I hit a nasty bump, took a while to locate that prob. The bummer was, that the computer available at the dealer is only rebuilt and not available new. Still cured the prob. for me.

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He needs to check for code 11 first in the computer. If there is a Crank or Cam position sensor problem this will drop the ASD/Fuel Pump relays and cut off power to parts of the igniton system and fuel pump, thus cranking and checking for voltage will show 0 after about 3 seconds. The fuel pump will not run if the computer does not see pulses from BOTH sensors.

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He needs to check for code 11 first in the computer. If there is a Crank or Cam position sensor problem this will drop the ASD/Fuel Pump relays and cut off power to parts of the igniton system and fuel pump, thus cranking and checking for voltage will show 0 after about 3 seconds. The fuel pump will not run if the computer does not see pulses from BOTH sensors.

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Overcomplicated, all you have to do is check for power at the pump and if there is no power work toward the front. Chances are he will have power and need a pump. If he was a tech and had a scanner, voltmeter and service manual the other way would be the way to go.

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He needs to check for code 11 first in the computer. If there is a Crank or Cam position sensor problem this will drop the ASD/Fuel Pump relays and cut off power to parts of the igniton system and fuel pump, thus cranking and checking for voltage will show 0 after about 3 seconds. The fuel pump will not run if the computer does not see pulses from BOTH sensors.

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Overcomplicated, all you have to do is check for power at the pump and if there is no power work toward the front. Chances are he will have power and need a pump. If he was a tech and had a scanner, voltmeter and service manual the other way would be the way to go.

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There wont be any power at the pump after 2 to 3 seconds after turning the key to on!! The electric pump does not recieve power all the time, if it did and you had an accident then it would spill gas all over the place and cause a fire. Checking for codes is simple and the first part of diagnostics. Using the key to retieve codes is very simple. There IS NOT Power to the fuel pump all the time...read up on the theory. With no power there due to the enginnering design your diagnostic tip is useless. No pulses from crank or cam position sensor and there is NO power at the pump.

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He needs to check for code 11 first in the computer. If there is a Crank or Cam position sensor problem this will drop the ASD/Fuel Pump relays and cut off power to parts of the igniton system and fuel pump, thus cranking and checking for voltage will show 0 after about 3 seconds. The fuel pump will not run if the computer does not see pulses from BOTH sensors.

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Overcomplicated, all you have to do is check for power at the pump and if there is no power work toward the front. Chances are he will have power and need a pump. If he was a tech and had a scanner, voltmeter and service manual the other way would be the way to go.

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There wont be any power at the pump after 2 to 3 seconds after turning the key to on!! The electric pump does not recieve power all the time, if it did and you had an accident then it would spill gas all over the place and cause a fire. Checking for codes is simple and the first part of diagnostics. Using the key to retieve codes is very simple. There IS NOT Power to the fuel pump all the time...read up on the theory. With no power there due to the enginnering design your diagnostic tip is useless. No pulses from crank or cam position sensor and there is NO power at the pump.

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Oh I know the theory, I have 22 years of Chrysler training to prove it. Again, if you read my earlier posts, you have to check for power WHILE CRANKING.I was trying to help the guy with his problem the EASIEST WAY with very little equipment. If he has power at the pump while cranking he need not look any further.I am done here,mojo if you have any questions, feel free to PM me. Good luck.

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Once again...you will NOT have 12 volts at the pump after 2 to 3 seconds IF the Cam Position Sensor or the Crank Position sensor is faulty while cranking! Read the theory again! The fuel pump relay ONLY supplies voltage to the fuel pump when the computer sees pulses from the sensors, if no pulse(as in bad sensor) that means NO voltage. So why check for voltage on a circuit that may not have it there by engineering design? The easiest way to do this is to use the ignition key and check for error codes first. Thats not too hard is it? Dont need a scanner for this. With your theory that the fuel pump gets voltage all the time would also mean that if injectors are pulsing along with the fuel pump running and there is no spark the engine would hydrolock with fuel! No way.
Now you could jumper the relay to test the wiring back to the fuel pump but then you have to be certain that 12 volts is actually leaving the relay before you go back to the fuel pump.

To the original poster, sorry for side tracking the problem but you must receive the correct information or you will be chasing ghosts.

I also have experience of 39 years.

Regards-Stevo

When PCM does not receive reference signal from ignition system, (indicating engine is not running), then the PCM interrupts relay ground circuit and no voltage is supplied to fuel pump , ignition coil, or oxygen sensor heater element.