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91 C4 Sizzle After Driving Around Driver Side Manifold
New C4 Owner. Bought a pretty well taken care of 91 C4. Drives great especially after warmed up. Noticed at cold start it takes a couple sometimes 3 tries to start.. once started it runs fine. Fuel pump sounds to be priming.. Did get a H32 Code that seems to pop up when highway driving and doesnt immediately come back. Drove it today and again it ran nice. Pulled it in the garage and went in and the wife complained of the house smelling like gas.. went to garage and opened the hood.. sizzle coming from driver side header or these intake manifolds? area sounds to be around front 2 headers area back to the hose that runs between them.. could this be a gasket leak? Would that cause strong gas odor well after driving? If there is small amounts of liquid pooled on headers is that fuel or coolant? Maybe none of this has to do with the strong gas odor? No leaks on floor.. Sizzle seems to be coming from this general area..
Last edited by C4 Explosivo; Mar 28, 2020 at 08:23 PM.
New C4 Owner. Bought a pretty well taken care of 91 C4. Drives great especially after warmed up. Noticed at cold start it takes a couple sometimes 3 tries to start.. once started it runs fine. Fuel pump sounds to be priming.. Did get a H32 Code that seems to pop up when highway driving and doesnt immediately come back. Drove it today and again it ran nice. Pulled it in the garage and went in and the wife complained of the house smelling like gas.. went to garage and opened the hood.. sizzle coming from driver side header or these intake manifolds? area sounds to be around front 2 headers area back to the hose that runs between them.. could this be a gasket leak? Would that cause strong gas odor well after driving? If there is small amounts of liquid pooled on headers is that fuel or coolant? Maybe none of this has to do with the strong gas odor? No leaks on floor.. Sizzle seems to be coming from this general area..
Your fuel rail and injectors are located in this area. Hope it's not fuel dripping onto the runners. Better check carefully.
Those don’t look like stock injectors. Someone had been in there.
start with a fuel pressure gauge and see if the system holds pressure. The hookup is on the passenger side of the fuel rail back near the regulator.
Ok will do. Im mechanically inclined but far from a mechanic.. I grew up working in a carbueurated straight 6 that had little major issues.. is that port the only place I can properly test fuel pressure? I only ask because I have a pressure gage but it doesnt have the metal fitting for the other end of the hose just different sized rubber fitting.. possibly junk im sure. I think its one you apply the pressure and see if it holds instead of reading the pressure provided? On the injector note I dont know enough to know at first glance like that.. though im looking online at how to's and im noticing things on mine that arent on theirs.. ill add some pics of what all im looking at and wondered what they are.. think the guy put some money into it.. What the heck is this thing? Its connected right in front of the fuel line valve and the fuel pressure regulator.. What is this?
Ok will do. Im mechanically inclined but far from a mechanic.. I grew up working in a carbueurated straight 6 that had little major issues.. is that port the only place I can properly test fuel pressure? I only ask because I have a pressure gage but it doesnt have the metal fitting for the other end of the hose just different sized rubber fitting.. possibly junk im sure. I think its one you apply the pressure and see if it holds instead of reading the pressure provided? On the injector note I dont know enough to know at first glance like that.. though im looking online at how to's and im noticing things on mine that arent on theirs.. ill add some pics of what all im looking at and wondered what they are.. think the guy put some money into it.. What the heck is this thing? Its connected right in front of the fuel line valve and the fuel pressure regulator.. What is this?
hmmmm. Interesting.. say thats what it is and the last owner never drained it.. could that thing be so full that its sucking it back in and causing vacuum issue or make it run rich? Just taking stabs.. ill go buy a better fuel pressure gauge and look for vacuum leaks as well.. appreciate the help
It’s a catch can. Empty it. You can delete it later on. Not a necessity. Here’s the fuel pressure tester I have. It’s nice because the end which hooks to the fuel rail has a slight bend making it easier to use.
the small black box with a green conn is the MAP sensor. Stock.
the other one on the pass side is the charcoal canister vent solenoid. Also stock.
there isn’t any other way to test fuel pressure. Your local shop may rent a kit that would work. I’d try that first...
if the fuel rail is indeed leaking, they have oring kits for the rails as well as injectors. There are also two where the fuel lines mate to the rails on the front pass side of the block. You’re going to need a top end gasket kit if you have to pull it apart. It’s actually very doable and just take your time and take pics / notes.
It’s a catch can. Empty it. You can delete it later on. Not a necessity. Here’s the fuel pressure tester I have. It’s nice because the end which hooks to the fuel rail has a slight bend making it easier to use.
the small black box with a green conn is the MAP sensor. Stock.
the other one on the pass side is the charcoal canister vent solenoid. Also stock.
there isn’t any other way to test fuel pressure. Your local shop may rent a kit that would work. I’d try that first...
if the fuel rail is indeed leaking, they have oring kits for the rails as well as injectors. There are also two where the fuel lines mate to the rails on the front pass side of the block. You’re going to need a top end gasket kit if you have to pull it apart. It’s actually very doable and just take your time and take pics / notes.
good luck.
Emptied the catch can.. grabbing a guage tomorrow after work to see what it looks like.. thanks for the info!
Well an update.. started it and warmed it up yesterday and not a drop of moisture on the engine as it had orginally.. took for a wash and came back.. ran great.. not a drop or smell of gas.. turned it off.. went inside.. wife complained.. went to garage and it was back.. looked all over.. looked at engine bay hoses and block.. nothing.. aired out garage a bit and smell went away once closed garage and didnt come back.. woke up this am.. no smell.. no leak.. backed out and parked to shut garage.. and the smell hit me in the face.. looked at opened hood no sprays or anything crazy. Looked underneath and gas was dripping off of my oil filter pretty steady.. shut it off.. if it running down my oil pan and filter where is it coming from most likely?
Fuel lines run on the passenger side of the car....then up to the fuel rails. It has be be from the fuel rails or fuel pressure regulator on the rails.
Check very carefully around each injector and at the fuel rail connections at the front of the car and then at the cross connection at the back of the engine where the rails are connected together. Don't drive it until you find the leak. You can turn the key on and pressurize the system and then look for the leak.
Last edited by bjankuski; Mar 31, 2020 at 06:56 AM.
Well an update.. started it and warmed it up yesterday and not a drop of moisture on the engine as it had orginally.. took for a wash and came back.. ran great.. not a drop or smell of gas.. turned it off.. went inside.. wife complained.. went to garage and it was back.. looked all over.. looked at engine bay hoses and block.. nothing.. aired out garage a bit and smell went away once closed garage and didnt come back.. woke up this am.. no smell.. no leak.. backed out and parked to shut garage.. and the smell hit me in the face.. looked at opened hood no sprays or anything crazy. Looked underneath and gas was dripping off of my oil filter pretty steady.. shut it off.. if it running down my oil pan and filter where is it coming from most likely?
Can you smell pressure? If not GET A GAUGE. Beg, Borrow or Steal one. Go to Autozone. They can sell you one or you can put $150 for a tool deposit. I can't smell pressure so good luck if you can. Stop using subjective scales and start using objective ones.
He does not need a fuel pressure gauge, he has fuel dripping off his oil filter that is leaking from the car somewhere, best guess from the fuel rail/injectors on the drivers side of the engine. Find the leak and fix it, a gauge will not find a leak.
He does not need a fuel pressure gauge, he has fuel dripping off his oil filter that is leaking from the car somewhere, best guess from the fuel rail/injectors on the drivers side of the engine. Find the leak and fix it, a gauge will not find a leak.
Just wondering if it comes from the pressure side or the return side of the fuel circuit.
Found it.! furthest rear injector on passenger side.. O ring was toast.. pouring out.. getting oring kit to change em all.. thanks for the help! Sure ill have more questions soon..
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91 C4 Sizzle After Driving Around Driver Side Manifold
