Truck stalled and engine cranks but won't start

Maintenance/Repairs
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1

My husband was driving his 1989 GMC suburban truck this morning and it was just fine no indication anything was wrong and it stalled out when he went to start it the engine cranked but would not start any ideas on what we should look at how we should look at it any ideas to help get his truck back on the road would be great thank you

2

Could be fuel pump, or fuel pump relay, could be ignition module, could be a lot of things. This model has throttle body fuel injection so take off the air cleaner and crank the engine to see if any fuel comes out from the two injectors. You can see them hung over the throttle bores. No fuel spray “cone”??Swap out the fuel pump relay from another in the fuse box. There should be another of the same type in there for another feature. If it starts, there’s your problem. If not, it is most likely the pump.

Ok, fuel but no start says “ignition”. Pull a spark plug wire and see if it has spark when cranking. No spark? Pull the distributor cap and cehck the coil resistance. Is it open circuit? Replace the coil. If the coil is OK, change the ignition module inside the distributor, and the cap and rotor, too while you are there.

Could also be the MAP sensor or the TPS sensor but I don’t think that would cause a no-start. It would be helpful if you pull the engine codes from this thing and post them here. Google “read codes for OBD 1 on a GM truck” to find out how.

That should lead you to the most likely problem but not all of them.

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3

One easy one is the fuel pressure regulator, easy check, Pull the hose off the regulator, if it has or smells of gas you need a new one

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Wrong engine, @Barkydog . That is an LS series V8, he has the old TBI Gen 1 engine.

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Sincere apologies, not sure about year listed, just trying to help, but there did seem to be some available.

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don’t know why repeat

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http://www.partsgeek.com/5rdr35w-gmc-c1500-fuel-pressure-regulator.html?utm_source=shopzilla&utm_medium=pf&utm_content=hc&utm_campaign=PartsGeek+ShopZilla&fp=pp&utm_term=GMC+Fuel+Pressure+Regulator&gclid=CjwKEAjwqZ7GBRC1srKSv9TV_iwSJADKTjaDCA8sEu-bp8DfMpOcu4RcOcknPLUT3hHLrhW6r2ZvlhoCz0_w_wcB

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Fuel pressure regulator on TBI models is part of injector assembly. No hose. If regulator’s leaking it will most likely still start or sputter due to fuel leaking into throttle body. It’s the way it was designed.

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There’s a chance of a bad ignition module, which could give you no injector spray AND no spark. But yet still have fuel pressure. Have seen it on these trucks plenty. Of course fuel pump failure is a likely culprit as well. Especially the hose rupturing between the pump and fuel delivery pipe. Unfortunately TBI trucks are a bear to check fuel pressure. If there’s no injector spray, try an alternate fuel source to see if it momentarily runs. If it does you’ll know it is a fuel issue.

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Ok so we have replaced the fuel filter and it still won’t start we also turned the truck on while the hose was off of the filter and no gas came out so from what were understanding that means that it is probably the fuel pump so we are in the process of draining the gas tank in order to get the fuel pump out I will keep you all updated and thank you so much for all of your input and your wonderful help

11

Before you do all that . . .

Have you verified proper power and ground at the fuel pump . . . ?

Does it briefly run on starting fluid?