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Discussion Starter · #1 ·
Have a tech question for everybody. I have a 1986 C4. I had new tires ordered for it so I decided to get the most out of the old ones. On the way home from work one morning I decided to stop and do a burnout on our country road. Now when I start the car instead of firing right up it cranks for about 5 to 10 seconds before starting. It use to start as soon as I hit the key. It only has 78000 miles on it but I'm lost when it come to all the injection business. Any ideas othe than stop doing burnouts.
 

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You need to start by checking your fuel pressure.. You should have a 2 second pump run with key on. The pressure should hold steady. This is the best place to start.
Side note: Probably coincidence that your burn out seemed to cause the starting issue. Doing a W.O.T. shouldn't create a driveability problem.
 

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Discussion Starter · #3 ·
I'll check it out. Thanks for the reply. I'll have to go get a pressure gauge. I replaced the fuel pump this spring. Other than hard starts it runs perfect.
 

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If you have spark on the first turn of the key, check the fuel pressure as mentioned. The fuel pump could be fine, but the fuel pump relay has failed causing the oil pump switch to close the circuit when 4 psi of oil pressure is made. A faulty fuel pump relay will cause long starts. You can bypass the relay by using a jumper wire and insert it into the first and last wires on the fuel pump relay harness. You can also use a jumper wire from the positive side of the battery and insert the other end into terminal G (lower left bottom) and the fuel pump should run until the wire is removed. Also, if there a difference in the engine being hot or cold?
 

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Discussion Starter · #5 ·
Ok, here's what we got
when I turn the key on the fuel pressure goes to 44 and then back to zero in about two seconds.
With the car at idle the fuel pressure is 36 and steady. Even when I rev the engine and hold it at mid throttle the pressure never goes above 36.
 

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The most common thing I've found on your type problem is the pump to meter hose leaking. Your pressure shouldn't drop after the pump shuts off. This will also cause bad running pressures.
 

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You may also want to pinch off your return hose and see if the pressure holds. This will insure that you don't have a pressure regulator problem.
 
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