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Discussion Starter · #1 ·
Hello. I thought it might be a fuel pump (130k on engine & car) causing the car to take to long to fire at times. I put a new F.P. in the tank. Still does it. It should take less than a second of cranking. It probably takes a full second.

Any ideas?

Thanx.
 

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Try pulling the vacuum elbow off the fuel pressure regulator, and make sure its not got gas in it. Also, if the fuel filter hasn't been changed in awhile, id get a new one. A half a second delay isn't much, but i know what you are talking about. My car developed an odd, short delay cranking like this a week ago. I went under the car and found that rats had chewed my vent line going from the gas tank to the evap canister in two at the tank. I fixed it, and now my car starts again as soon as you touch the "start" position, or on the second "grunt" of the starter. (my delay was worse when the car had already been running, and you went to restart it).
 

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Discussion Starter · #3 ·
Try pulling the vacuum elbow off the fuel pressure regulator, and make sure its not got gas in it. Also, if the fuel filter hasn't been changed in awhile, id get a new one. A half a second delay isn't much, but i know what you are talking about. My car developed an odd, short delay cranking like this a week ago. I went under the car and found that rats had chewed my vent line going from the gas tank to the evap canister in two at the tank. I fixed it, and now my car starts again as soon as you touch the "start" position, or on the second "grunt" of the starter. (my delay was worse when the car had already been running, and you went to restart it).

Thanx DIGGM. I will definitely try the vacuum elbow thing tomorrow. Today, after work, I grabbed a fuel filter from Car-quest. Your symptom of having it being worse after driving for a bit is the same as my scenario. Is the line visible w/o tank removal?

Thanx again.
 

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Yes, I actualy slid under the back of the car with the car up on a jack stand under the very back of the frame. I didn't even get the wheel off the ground, but this is a 9c1! At the front of the fuel tank, its the one on the left out of the three lines sticking forward from the top of the tank, the only line there that doesn't have those quick disconnects on it.
 

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Discussion Starter · #5 ·
Yes, I actualy slid under the back of the car with the car up on a jack stand under the very back of the frame. I didn't even get the wheel off the ground, but this is a 9c1! At the front of the fuel tank, its the one on the left out of the three lines sticking forward from the top of the tank, the only line there that doesn't have those quick disconnects on it.



Radical! Very useful information! I will hit it this Fri. or early Sat.

Thanx.
 

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Discussion Starter · #7 ·
Thanx BALLSS. Hey, stupid question, where is the regulator on an LT1?

Thanx.
 

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Thanx BALLSS. Hey, stupid question, where is the regulator on an LT1?

Thanx.
back of the intake manifold at the top.

It's connected to the fuel rail and has a little rubber elbow going into it.

 

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Discussion Starter · #9 ·
Could not ask for a more detailed photo! Thanx Guillaume!
 

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Discussion Starter · #10 ·
OK. I just went & looked at the lil' elbow. No fuel inside. Then I remembered that the other day when I filled up, when I undid the gas cap, it sounded like vacuum city. So I removed the cap again, and same, loud, vacuum noise. W/it off, it started properly. I will still change the filter because I already bought it, and I don't Think it has been changed (previous owner kept every lil' receipt and a list w/dates of repairs. Hopefully a new gas cap will fix things.
 

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Discussion Starter · #11 ·
Well. Different gas cap. After I got home from putting on an new gas cap, same thing. I undo the gas cap, starts right up. Is there another, idea I can try? Is there another vent set up I need to try?

Any tips?
Thanx.
 

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I always get pressure when opening my gas cap (when my vent line was chewed i was getting nothing). There has been discussions here regarding the EVAP canister getting full of gas, and causing vacuum to build in the gas tank due to it not venting properly (ive read some people just disconnect the vent from the canister, but then theres the issue of delayed starting due to the fuel tank being vented constantly). Ive not had to deal with the EVAP canister itself personaly, but i know there are members here who have and can chime in with the specifics.
 

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Discussion Starter · #13 ·
Thanx for all your time DiGGM95. I am hoping I can keep contact w/this forum long enough to fix this (usually I can't connect, I have read the Wolf's stuff and even PM'd him).

I unplugged the FPR & blocked the hose to the engine. It has started up quickly, like it should. But I reported the same thing after loosening the gas cap, then later on, too much cranking again. I get no gas leaking out of the FPR (started it, let it run, then started it a few times again).

While in the garage, the exhaust smells like unburnt fuel. Do you think I have a leaking injector?

Tech tips?

Thanx so much for helping me. I am new to LT1's, but I am appreciating people taking their time to help me.
 

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Discussion Starter · #14 ·
O.K. Did a lil' family stuff today and I borrowed a FP gauge from my bro. It should stay about 40 while running and how long after shutting down?

Thanx.
 

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You can check for a leaky injector by pulling the injector/fuel rail assembly, and with the fuel lines connected, turn the key on to pressurize the injectors and watch for drips. (be very careful with the fuel lines, even if you have to disconnect them to remove/install the rail, and dont forget to bleed the pressure w/the schrader valve when removing the lines). I still suspect a problem with the EVAP system, as you report vacuum instead of pressure when removing the fuel cap. Maybe the charcoal in the canister has degraded, and a piece of it has the evap purge solenoid hanging?
 

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O.K. Did a lil' family stuff today and I borrowed a FP gauge from my bro. It should stay about 40 while running and how long after shutting down?

Thanx.
Mine holds for awhile and gradualy bleeds down, but when my original pump was causing problems, it would drop very quickly after the pump quit running. What psi do you get with just the key turned on?
 

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Discussion Starter · #17 ·
You can check for a leaky injector by pulling the injector/fuel rail assembly, and with the fuel lines connected, turn the key on to pressurize the injectors and watch for drips. (be very careful with the fuel lines, even if you have to disconnect them to remove/install the rail, and dont forget to bleed the pressure w/the schrader valve when removing the lines). I still suspect a problem with the EVAP system, as you report vacuum instead of pressure when removing the fuel cap. Maybe the charcoal in the canister has degraded, and a piece of it has the evap purge solenoid hanging?

Hello DiGG95. I will look into the evap stuff more. I must say it was a big vacuum noise, I am not sure if air was going in or out. I better check. I will report back.

Thanx again DiGGGM95!!!
 

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Discussion Starter · #18 ·
I got a lil noise on the gas cap, but could not tell. I think I need to take it for a lil' spin. I did pop on the FP gauge. It stays right around 40. I turn the ignition on, it hits like 50, then goes sits at 40. Then when fired it stays @ 40. When I turn it off, it quickly goes a bit below 40, but stays there w/o slowly dropping.

Is any of that info useful?

I have not even seen where the charcoal canister is yet on this bad boy. It still smells like fuel when running.

Thanx again DiGGM95.
 

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Hmm, fuel pressure is holding good, but it seems a bit low. Mine goes up to 47 psi without the engine running, once cranked, it goes down to 41 psi with the regulator vacuum elbow hooked up. Before messing with the canister, try taking a drive with the fuel psi gauge taped to the windshield and see if the pressure stays up when under load.
 

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Discussion Starter · #20 ·
OK, did a better test in daylight.

Ignition on - goes to 45, then a click, pops to 40 and stays there

running - stays right at 42-ish

full throttle - 44/45 -ish

turn off the motor - sits at 39 and stays there, does not budge until I get out & pop it of Mr. Schrader.


Any ideas?

Thanx.
 
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