Author Topic: 1987 TBI Hard Starting  (Read 9146 times)

Offline MarkS

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1987 TBI Hard Starting
« on: November 06, 2009, 05:00:01 PM »
Hi guys,

I have a 1987 350 TBI and it seems it takes more turns to start than it should. The truck is a 35K documented miles but we all know it's tough to know for sure. Hot or cold the engine has to turn about 4 seconds before it starts. I also noticed when it's cold it runs slightly rough and the idle varys a bit. Any ideas? I thought about cleaning the TB and replacing the injectors.

What would be the logicial steps troubleshooting the issue?

Offline Layne

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Re: 1987 TBI Hard Starting
« Reply #1 on: November 06, 2009, 06:37:57 PM »
how are the plugs, wires, cap and rotor?  Possibly air idle control- about 25-50 dollars. Any check codes?
77 c-10 - 77 400 86 700r4 "Emmy"
83 citation - 2.5L Four on the Floor!
88 sierra - reman 350 700r4 "Eleanor"
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Offline zieg85

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Re: 1987 TBI Hard Starting
« Reply #2 on: November 06, 2009, 06:43:55 PM »
Turn the key on to let the fuel pump run until it shuts off.  Turn the key back to off.  Turn the key back on and repeat.  Then try starting it.  If it starts better or in half the revolutions your fuel pump is getting weak.  Just went through a similar situation on a TBI 95.  Won't cost you anything to try.  My $.02
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline dumbucket1

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Re: 1987 TBI Hard Starting
« Reply #3 on: November 06, 2009, 06:45:39 PM »
4 seconds to start is about how long it takes all of my tbi trucks to start.
Chevy and GMC trucks ranging from 1973 to 2007

Offline dunedigger

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Re: 1987 TBI Hard Starting
« Reply #4 on: November 06, 2009, 06:53:47 PM »
My 87 has taken that long to start since new I bet.  Fuel pressure has to build up for the tbi.  I have dual tanks and when I'm on my pass tank it takes just a second or two longer to start but has been that way for 12 years now that I've had it and still going.  I love having two fuel pumps so if one goes out I should still have a ride home.

Offline MarkS

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Re: 1987 TBI Hard Starting
« Reply #5 on: November 06, 2009, 07:58:59 PM »
Plugs and wires good... haven't checked the cap and rotor.

The fuel pump check is a good idea.

4 seconds maybe be right. I keep trying to compare it to my EFI... not quite the same :(