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i have a 1990 ford pickup half ton and when you drive ...
Sent to Car Experts August 14 12:30 AM

i have a 1990 ford pickup half ton and when you drive it 5 miles or so about long enough to get the engine to a warm temp its like you turn off the key everything shuts down gages everything, two hours later you can re start it

 

Optional Information:
1990 f150 lariat 361

Already Tried:
replace the coil

Customer (name blocked for privacy)
Answer
August 14 7:38 AM (6 hours and 51 minutes and 11 seconds later)
         
ACCEPTEDCheck Mark

In order to troubleshoot the problem accurately, some things have to be tested during the actual problem. Any other time and everything will check out good. Trying to diagnose this any other way amounts to guessing and that is just not accurate by any technician.

Every engine requires spark, fuel and compression to run. That's what we have to look for.
You need to first test a few functions during the failure. Many of these functions share common resources so it's important to test all the functions even if we are already aware of one that has a problem.

 

1) Test for spark at the plug end of the wire using a spark tester. If none found, check for power supply on the + terminal of the coil with the key on.


2) Test for injector pulse using a small bulb called a noid light. If none found, check for power supply at one side of the injector with the key on.


3) Use a fuel pressure gage to test for correct fuel pressure, also noticing if the pressure holds when key is shut off.

Once you have determined which of these functions or which combination of them has dropped out,
you will know which system is having the problem.

Here's what the noid light looks like.

Images available only to Customers.




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August 14 9:35 AM (1 hour and 57 minutes and 25 seconds later)
         
Reply to Tyler Stevens's Post: the engine turns over Im not real shure about the gages
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