question on CSV testing
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Le Mans Master
Joined: Feb 2006
Posts: 8,753
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From: Louisiana
question on CSV testing
I have followed the FSM and tested the cold start injector on my 86 vette. I used an ohm meter and get 4.2ohm at the injector. I used a test light and voltmeter at the connector harness and get nothing when key is turned on for <8 sec. I am going to locate the bi-metal switch which is the probable cause, other than faulty wiring beyond the switch, of no harness power. I suspect the CSV of leaking fuel causing my rich condition. Should the CSV be closer to 16ohms like the injectors? Also does anyone know off hand where the switch is located?
- 1986 Original Owner -
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From: North Yorkshire, England
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DJ,
I just went and checked a new CSV I had on the shelf. It was 3.6Ohms. One of my original 8 injectors read 15.7. Your readings seem to agree with what I see.
The switch is located here:
It only gets power when the ignition is in the START position. There is also a 5 amp fuse in the Auxiliary Fuse Block behind the DIC:
I just went and checked a new CSV I had on the shelf. It was 3.6Ohms. One of my original 8 injectors read 15.7. Your readings seem to agree with what I see.
The switch is located here:
It only gets power when the ignition is in the START position. There is also a 5 amp fuse in the Auxiliary Fuse Block behind the DIC:
Last edited by Ray Quayle; Apr 22, 2006 at 12:45 PM.
- 1986 Original Owner -
Joined: Apr 1999
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From: North Yorkshire, England
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Let me know how you make out. I don't think this line of troubleshooting will help if you suspect a leak though. The valve only gets power when coolant is below 95°F and cranking. If everything is working correctly a test light or volt meter won't show anything unless you are cranking and coolant temp is below 95°F. If you are cranking and below 95°F, the amount of time the light will light vary depending on coolant temp but never more than 8 seconds. At 80°F say, it would only light while cranking for maybe 1 second. You normally won't crank for 8 seconds anyway. What I'm saynig is, if all this check out, it still won't tell you if your valve is leaking. The valve could leak even if it is never commanded open. What did your fuel pressure leak down checks show? If you are leaking down and suspect the switch, disconnect it and see what happens with leak down. If it still leaks down, it isn't that hard to remove the screw and pull the valve out of its bore to see if it's leaking. Much easier than pulling the other 8!
Melting Slicks
Joined: Oct 2002
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From: Cincinnati Oh
Get a block-off plate, cap the fuel rail where it's attached, and swap up to a 1989 memcal (or have someone flash the BIN onto your existing chip).
A little bit of work but at least you wouldn't have to spend premo $$$ to replace it.
A little bit of work but at least you wouldn't have to spend premo $$$ to replace it.
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Le Mans Master
Joined: Feb 2006
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From: Louisiana
Alright, I checked the 5a fuse behind the DIC and it was blown. I replaced it but need to wait a while because I idled the car to normal temp about an hour ago. My fuel pressure reading show: approx. 39-40psi idling, when I shut the engine off it leaks down approx. 2 psi every minute. After a day or so the pressure shows 10 psi before I attempt to crank. Seems slow but I've just about ruled everyting else out. I will get back after the engine cools down so I can test the wires. The other 8 injectors were replaced with 24lb about 2 months ago.
Team Owner
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From: Summerland B.C. Canada
Originally Posted by RRT vette
I suspect the CSV of leaking fuel causing my rich condition.
Originally Posted by RRT vette
The other 8 injectors were replaced with 24lb about 2 months ago.
Thread Starter
Le Mans Master
Joined: Feb 2006
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From: Louisiana
It runs rich in open and closed loop even after a WOT run. When in open loop I still have an up and down idle, but when engine warms up in closed loop it idles like a champ. I have done all the necessary step to the IAC, TPS, min idle, watched for open sparks, set timing 6*, cleaned TB, New PCV, fuel press o.k. idle and driving, new o2 sensor, new air filter, no codes. Last night I drove it to the store and seemed like when I came off throttle and came to a stop the idle was high and after aprox. 3 sec it would idle down normal. It acted like it was getting too much fuel to use at one time. In field test mode the ecm reconizes the rich condition in closed loop but doesn't seem to compensate. When cold idle with the up and down I do hear a hissing sound coming from the egr solenoid area when at lowest idle but have used propane and wd-40 and no change in idle. I have had plans to get it on a scan tool but haven't yet. When starting cold it acts like it wants to crank (stumbles, hunts) but dies unless I give it a little throttle, but also the CSV is not working now. Warm start it starts on first turn, not problem.
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Thread Starter
Le Mans Master
Joined: Feb 2006
Posts: 8,753
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From: Louisiana
New update, I tested the CSV connector this morning after replacing the fuse and the connetor is good now. I plugged it on the CSV and now the engine starts in one turn of the key cold but still hunts for idle for about 5-7 sec. before it finds it. Still the up and down idle as before.