Smell raw fuel while trying to start
Thread Starter
Racer
Joined: Aug 2006
Posts: 442
Likes: 0
From: Albany Oregon
Smell raw fuel while trying to start
Lately it's been getting harder and harder to start in the colder wet weather. Not sure what it could be. I usually seem to get it to start after minutes of trying but now it will not start at all. It will turn over but not fire. It sounds like it tries to start but just won't stay running. Why am I smelling raw fuel? Could the injectors be crap? Could it be the fuel pressure regulator allowing fuel to dump in the cyl and flood it?
93 6speed
I should probably mention, it doesn't have a fuel leak. I looked. I smell the raw fuel out back by the exhaust.
93 6speed
I should probably mention, it doesn't have a fuel leak. I looked. I smell the raw fuel out back by the exhaust.
Thread Starter
Racer
Joined: Aug 2006
Posts: 442
Likes: 0
From: Albany Oregon
Le Mans Master
Joined: Oct 2008
Posts: 9,758
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From: Houston Texas
As long as you turn the key it will keep pouring in. If you get enough gas it will wash past the piston rings into your oil.Check your oil if it has gas in it change it immediately. You also need to ck for spark at the plugs.
Thread Starter
Racer
Joined: Aug 2006
Posts: 442
Likes: 0
From: Albany Oregon
Ok I'll check that too. Would you know why it starts fine when it's warm? It's when I let it sit overnight and try to start it in the morning it gives me hell and is almost impossible to start. What part(s) does that sound like?
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Le Mans Master
Joined: Jan 2006
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From: Orlando FL
Pull off the vacuum line of the FPR and see if it is wet with fuel. You can also turn the key to on, then off to pressurize the system. Then take the vacuum line off watch and see if it drips. If it does it is bad.
You can also connect a short hose on the FPR and put hose in cup and see and measure what comes out.
Burning Brakes
Joined: Aug 2010
Posts: 924
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From: Manteca Calif
I'll bet the fuel pressure regulator (FPR) is defective. Overnight the fuel is coming back thru the vacuum line into the manifold and filling it with fuel. So in the morning you are loaded up.
Pull off the vacuum line of the FPR and see if it is wet with fuel. You can also turn the key to on, then off to pressurize the system. Then take the vacuum line off watch and see if it drips. If it does it is bad.
You can also connect a short hose on the FPR and put hose in cup and see and measure what comes out.
Pull off the vacuum line of the FPR and see if it is wet with fuel. You can also turn the key to on, then off to pressurize the system. Then take the vacuum line off watch and see if it drips. If it does it is bad.
You can also connect a short hose on the FPR and put hose in cup and see and measure what comes out.
Race Director
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I'll bet the fuel pressure regulator (FPR) is defective. Overnight the fuel is coming back thru the vacuum line into the manifold and filling it with fuel. So in the morning you are loaded up.
Pull off the vacuum line of the FPR and see if it is wet with fuel. You can also turn the key to on, then off to pressurize the system. Then take the vacuum line off watch and see if it drips. If it does it is bad.
You can also connect a short hose on the FPR and put hose in cup and see and measure what comes out.
Pull off the vacuum line of the FPR and see if it is wet with fuel. You can also turn the key to on, then off to pressurize the system. Then take the vacuum line off watch and see if it drips. If it does it is bad.
You can also connect a short hose on the FPR and put hose in cup and see and measure what comes out.
My 89 had similar symptoms. The scary part was fuel was working its way through the throttle body and leaking out the air filter. I have a gas water heater in my garage. Fortunately no fumes hit the pilot. The FPR cured my problem.
Thread Starter
Racer
Joined: Aug 2006
Posts: 442
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From: Albany Oregon
Ok, I'll do the FPR thing tomorrow. Would it be best to do it prior to trying to start it in the morning to make sure any fuel is out of the intake or should I do it after I get it started, "if" I get it started?? That way I could see if it worked the following morning.
I looked in my factory service manual and there's really not much about the FPR remove/replace functions. Any tips on how to do that?
I looked in my factory service manual and there's really not much about the FPR remove/replace functions. Any tips on how to do that?
Pro
Joined: Feb 2006
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2021 C4 of the Year - Unmodified Finalist
load test
Load test your battery. If it does it when it is cold it could be your battery is getting ready to puke. A cold, weak , (sacked) battery can have enough juice to turn the engine over like gang busters but nothing left for the secondary circuit.
Just a thought.
Just a thought.
Le Mans Master
Joined: Jan 2006
Posts: 5,621
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From: Orlando FL
Ok, I'll do the FPR thing tomorrow. Would it be best to do it prior to trying to start it in the morning to make sure any fuel is out of the intake or should I do it after I get it started, "if" I get it started?? That way I could see if it worked the following morning.
I looked in my factory service manual and there's really not much about the FPR remove/replace functions. Any tips on how to do that?
I looked in my factory service manual and there's really not much about the FPR remove/replace functions. Any tips on how to do that?
Then right away I would depressurize the system. If you have a fuel pressure tester with a pressure release button and output vent, put a hose on it and dump fuel into a cup. Or use any way you're comfortable and get some paper towels for spillage.
It is an easy replacement, a few bolts and hose connections and your done.
When mine went bad, it would dump almost 2 ozs of fuel into the engine over night. I felt like I had a new engine after it was replaced.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
I would check the FPR first. Pressurize the system and see how fast the fuel drops. If it falls quickly, clamp off the return line and see what happens. If it stops falling off, the FPR is shot.
I don't bother to check the fuel injectors. Nothing I have to check it with anyways. After 178K, I can't see anything wrong with taking it out and sending it off to FIC for a cleaning and check.
If it were me, I'd replace the FPR at the same time too.
I don't bother to check the fuel injectors. Nothing I have to check it with anyways. After 178K, I can't see anything wrong with taking it out and sending it off to FIC for a cleaning and check.
If it were me, I'd replace the FPR at the same time too.
Thread Starter
Racer
Joined: Aug 2006
Posts: 442
Likes: 0
From: Albany Oregon
I would check the FPR first. Pressurize the system and see how fast the fuel drops. If it falls quickly, clamp off the return line and see what happens. If it stops falling off, the FPR is shot.
I don't bother to check the fuel injectors. Nothing I have to check it with anyways. After 178K, I can't see anything wrong with taking it out and sending it off to FIC for a cleaning and check.
If it were me, I'd replace the FPR at the same time too.
I don't bother to check the fuel injectors. Nothing I have to check it with anyways. After 178K, I can't see anything wrong with taking it out and sending it off to FIC for a cleaning and check.
If it were me, I'd replace the FPR at the same time too.
I do intend on having the injectors gone through. Who is FIC? I hear it's cheaper to get the oem injectors rebuilt than to buy new ones.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
I'm going to tear into it tomorrow morning and do the FPR. I didn't see anything in the FSM about this but I'm assuming the injector rail will have to come off. After looking at it, that was my guess.
I do intend on having the injectors gone through. Who is FIC? I hear it's cheaper to get the oem injectors rebuilt than to buy new ones.
I do intend on having the injectors gone through. Who is FIC? I hear it's cheaper to get the oem injectors rebuilt than to buy new ones.
http://fuelinjectionconnection.com/
Thread Starter
Racer
Joined: Aug 2006
Posts: 442
Likes: 0
From: Albany Oregon
Ch@os, thanks for the vid. I have the LT1 and this appears to be L98? My distributor is under the water pump in the front of the engine though. Does anyone know of a walkthrough on the FPR replacement? I went to a mechanic shop yesterday and they quoted me 2 hours @ $80 per hour! That's $160 for this fix! Fu&$ that! I didn't do it. This has to be something that shows up in the FSM but I just can't find it and really starting to wonder why. We even looked in a Chiltons and didn't find it. If you find it in your FSM please let me know what page it's on. Thanks