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Tim's Auto Repair
Tim's Auto Repair, Mechanic
Category: Car
Satisfied Customers: 15576
Experience:  Have owned a repair shop for 25 yrs.
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GMC Sierra 3500 pickup: I have a 1990 GMC sierra 3500 7.4 TBI.

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I have a 1990 GMC sierra 3500 7.4 TBI. It willrun for about 50 miles then after it is turned off for a while it won't start for about 8 hours. it gets fuel through the fuel line to the throttle body but not through the injectors. I have replaced the throttle position sensor and the idle air control valve, rebuilt the TBI and checked the fuses. What is next?

Tim's Auto Repair :

hi

Tim's Auto Repair :

you have one of two posible problems

Tim's Auto Repair :

1- the ignition module

Tim's Auto Repair :

2-the pick-up coil

Tim's Auto Repair :

either of these can do this and sense the problem is intermediate,it would be hard to test them

Tim's Auto Repair :

i would replace the ignition module first

Tim's Auto Repair :

if it is the pick-up coil,,you may concider replacing the complete distributer with a new rebuilt unit,,sense it will need to come out and apart to replace the pick-up

Tim's Auto Repair :

the reason it isnt sqirting fuel after it gets hot though the injectors,,is because the computer doesnt know the engine is turning because of the bad component

Tim's Auto Repair :

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Tim's Auto Repair :



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Customer:

Thanks Tim, I will give this a try as soon as I can. I'm a weekend shade tree mechanic (or maniac I'm not sure which) I'll give this a shot and let you know.

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