Starting difaculty
Thread Starter
3rd Gear
Joined: May 2007
Posts: 3
Likes: 0
Starting difaculty
Hello I have a 1985 w/ new motor, trans, exhust, many sensors, no more emissions and have cleaned everything that needs it I think. It runs srong but, when I try to start it up it cranks for 3or4 sec and I stop try again and it pops right off. If I where to just hold it till it started it would take 6or7 seconds. Fuel pressure seems ok any thoughts?
Burning Brakes
Joined: Dec 2006
Posts: 904
Likes: 0
From: Virginia Beach VA
I have the same problem. The only time it starts right up is if I had just run it and say, went into 7-11 and pick up a drink and then walked back out. Any more time than that, it would take about 6 or 7 seconds to start.Matt
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
Any kind of smoke puff out the back when it finally fires?
Things on my mind...
Things on my mind...
- Your timing is off.
- Your fuel injectors are leaking.
- Your cold start injector has failed in some manner.
- You're running too rich.
Burning Brakes
Joined: Dec 2006
Posts: 904
Likes: 0
From: Virginia Beach VA
Hmm... mine does have a puff of smoke. I have changed the fuel pump and I actually had a few days of successfully firing right when I turned the key. I changed the injectors as well, but my car wasnt tuned for 30# injectors so it was drowning the cylinders (my engine was bogging down). I changed the injectors back and now I still have the same problem. Next time I get it tuned, I will definately have it tuned to the new injectors and check it out. Where is the cold start injector and how much does it cost/how hard is it to replace?
Matt
Matt
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
cold start injector
they stopped using the cold start injector in 1989.
below that year, it is plumbed in the back end of the left fuel rail and is positioned under the last intake runner on the left side.
below that year, it is plumbed in the back end of the left fuel rail and is positioned under the last intake runner on the left side.
Melting Slicks
Joined: Jan 2004
Posts: 2,659
Likes: 3
From: Oxford CT
I always wonder about this poor start aswell.
I feel like a norm car take 1-2 seconds to start
My vette takes 4-5 seconds seconds to start, i turn it over and just when I would stop to let the starter take a brake, I hold it on for that extra second and Bang, Its on.
I feel like a norm car take 1-2 seconds to start
My vette takes 4-5 seconds seconds to start, i turn it over and just when I would stop to let the starter take a brake, I hold it on for that extra second and Bang, Its on.
Team Owner
Joined: Jan 2003
Posts: 20,298
Likes: 240
From: Summerland B.C. Canada
Test your fuel pump relay. If it fails your now relying on the oil pressure switch(back up power) to supply the pump with power. It will take a few seconds till there is enough oil pressure to close the switch. Also, take a close look at the wires going into fuel pump relay connection. The insulation will probably have shrunk back enough to allow a short between wires.
http://members.shaw.ca/corvette86/Fu...mDiagnosis.pdf
http://members.shaw.ca/corvette86/Fu...mDiagnosis.pdf
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Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
If the cranking time is longer when the engine is cold (<95*), I would check the CSV ciruitry nd related. The CSV is not controled by the ECM, where as the injectors are.
If the cranking time is longer when the engine is warm (>95*), I would check the injectors and wiring, fuel pump circuirty...as in relay and wiring/connections.
Do a search or advanced search for CSV. With the advanced search use my screen name and check the archives. I have explained many times how the CSV circuitry works.
If the cranking time is longer when the engine is warm (>95*), I would check the injectors and wiring, fuel pump circuirty...as in relay and wiring/connections.
Do a search or advanced search for CSV. With the advanced search use my screen name and check the archives. I have explained many times how the CSV circuitry works.
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
You guys need to hook up the FP guage...turn the key to the ON position and see if the system primes. You should be able to hear it also for about 2 seconds.That should tell you if the relay is good/bad. Not to say you can't have an intermittent relay problem and like Agent86 said inspect the wires going into the relay...that's where I found my problem. Doesn't sound like a CSV to me, if you've driven the car to where it's warmed up and you're still experiencing the problem.