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5/14/13 9:22am - Original Message: 'Hard to Start, when cold starting.'
OEFOIFVETwithVETTE
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Annandale, VA - USA

Vette(s):
1988 C4 L98 Auto

Joined: 5/14/2013
Posts: 10
1988 L98 Auto.
recently aquired.
hard to start from cold start.
literally 3-7 seconds on the starter.
New wires, not plugs.
new cap and rotor.
once she starts i get a puff of smoke, not oil....smells like old fuel. (3rd new tank of fuel)
trust me being a Jeep guy I know oil smoke smell.
Once she is running, she starts slow then idles fine. after that no performance issues.
runs hard and great mileage for a V8.
16-18 city.
any ideas?
i have not changed fuel filter, and I have a New K&N air filter.
i dont think its plugs, rapid fires are in there, and they look to be pretty new, no rust or burning on the outside ceramic.
Also is that VATS bypass from Ecklers worth it?
or can I just wire in a toggle myself?
anyone done it?
did it work well?
will also post about this in a new thread in electrical.
Thanks in advance guys!
 
Jason
 


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5/14/13 6:28pm - Reply: 'Re: Hard to Start, when cold starting.'
CaledoniaBrian
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, - Canada

Vette(s):
1988 Convertable

Joined: 11/3/2011
Posts: 148
I just saw this now after commenting on your VATS question in another thread.
Curious why you would relate these issues with VATS. ??????
The VATS will not cause any of these issues. If your the Vats is not reading your key...you will have a no crank situation. Security light will also be flashing.


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5/15/13 5:38am - Reply: 'Re: Hard to Start, when cold starting.'
OEFOIFVETwithVETTE
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Annandale, VA - USA

Vette(s):
1988 C4 L98 Auto

Joined: 5/14/2013
Posts: 10
Not grouping together just 2 separate issues. 2 of the main things I need to address with the car? So no idea on the hard start? Or just picking on the new guy for asking 2 questions? :P

____________________________________
1988 Chevrolet Corvette
1976 Jeep CJ7
1998 Jeep Grand Cherokee
2000 Jeep Cherokee Limited
 
One of these things is not like the others......one of these things will always belong!
 
OEF 06-07
OIF 07-09
OEF 10-11
Staff Sergeant
Infantry
Purple Heart 2008 Iraq 
Stuck in The Old Guard.......HELP send REAL Soldiers Time NOW!!!
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5/15/13 6:14am - Reply: 'Re: Hard to Start, when cold starting.'
CaledoniaBrian
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, - Canada

Vette(s):
1988 Convertable

Joined: 11/3/2011
Posts: 148
Not picking on the new guy at all. Just thought it funny to relate these problems with the VATS.
 
 As for your cold start..... could be a few things. I would start with checking the fuel pressure. From the sounds of the symptoms this may be a leaky injector. ...... but that is just a thought on my part. Others; more knowledgeable than me may chime in...........  


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5/17/13 12:00pm - Reply: 'Re: Hard to Start, when cold starting.'
djsroknrol
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Altus, OK - USA

Vette(s):
1984 L83/MD8 coupe

Joined: 2/7/2011
Posts: 122
I would also look at the TPS to make sure it's adjusted to spec....Wink

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5/19/13 7:12am - Reply: 'Re: Hard to Start, when cold starting.'
eddie20890
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lanoka harbor, NJ - USA

Vette(s):
1990 L-98 white/ red/black leather interior targa top auto 1975 L48 blue/black leather interior t tops auto

Joined: 3/22/2009
Posts: 1363
OEFOIFVETwithVETTE said: Not grouping together just 2 separate issues. 2 of the main things I need to address with the car? So no idea on the hard start? Or just picking on the new guy for asking 2 questions? :P


first welco9me to the site and dont think anyone was picking. i myself thought you were tieing the two topics together.

i would change the fuel filter just to be on the safe side unless you know when it was changed. on an 88 there is a 9th injector for cold starts. the other thing to check is the IAC.

all the other things need to be checked also. if you can get the FSM for the 88 it has all the test procedures in it. and makes it a lot easier to work on the car.

good luck and let us know how yo9u make out.


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3/17/16 12:19pm - Reply: 'Re: Hard to Start, when cold starting.'
Tesla220
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Joined: 4/23/2015
Posts: 64
Check fuel pressure . fuel pump relay should energise supplyng power to the fuel pump for 3-5 secons after you turnt eh key to the on position. It should build up spec fuel pressure in that time.  After the engine is running power to the FP is supplied through the Oil Pressure Sender direcly to the pump. So if your FP relay is bad it can cause the FP not to get power till the Oil Pressure builds up high enough.

1. Check F Press while cranking. if it comes up slow then cycle the key every 5 seconds till it comes up to spec. If it drops quickly it may have a leaky injector or pressure regulator. if it holds pressure ok but under spec then it needs a FP.

2. if pressure does not come up when key is turned on check power at the pump. use only GM, AC Delco or Denso pumps.




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3/23/16 3:03pm - Reply: 'Re: Hard to Start, when cold starting.'
wolfuser
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Vette(s):
1987 C4 convertible 350ci auto white / red / white top appx 18k mls

Joined: 11/15/2012
Posts: 12
that sounds like a good one. it s a somewhat peculiar feature that the fuel pump is energized in 2 separate ways, by the ecu and the oil press sensor. so one could get a slow start situation cause the fuel pump is only turned on when oil press is present. 
this would mean that one should get a normal start by bypassing the fuel pump relay (unplug relay, temporarily connect switched voltage terminals by suitable wire)

good luck
Wolfram
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3/29/16 11:05am - Reply: 'Re: Hard to Start, when cold starting.'
Tesla220
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Joined: 4/23/2015
Posts: 64
yes. That is true.

  Also a system like this is the simplest as if you are in any kind of accident the FP shuts off if the engine shuts down for any reason at all. It also allows the FP to run without having to energize a relay continuously and it eliminates an impact sensor that some manufacturers use.

Replace the fuel filter first. Dirty F Filters are IMO the #1 cause of failed F pumps in GM and Fords. 

  There is a FP pressure port right on top of the engine. You should see the pressure build right up to spec when you turn the key to the on position. This verifies FP relay operation. It should hold pressure for a while too..a couple minutes. 

I also like the idea of checking the 9th injector used on the one or two year corvettes, this injector will cause the exact same symptom as a weak/bad F Pump or inoperative relay. This injector is sometimes referred to as a "Cold Start Valve"  also called a "Cold Start Injector". Very popular item in many systems made by Bosch. (Nissan, Toyota, and Euro-makes)



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7/26/17 4:02pm - Reply: 'Re: Hard to Start, when cold starting.'
aeronautic1
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Pompano Beach, FL - USA

Vette(s):
1988 Coupe

Joined: 7/9/2013
Posts: 4
Sounds to me like the Number 9 fuel injector (yes, there are 9 fuel injectors) is not atomizing. It was an AC/Delco part not in production. Every once in a while one pops up on eBay. That's how I got my hands on one last year.

(Cold Start Injector [#9] squirts raw fuel into the intake manifold when cold giving the L98 and extra SHOT)


|UPDATED|7/26/2017 2:02:27 PM (AZT)|/UPDATED|


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