Sonia_Blades

So I’m in Phoenix AZ, I have an 89 white on blue C4. I recently did a fuel pump assembly swap and it solved my “turning off” problem however, it is now leaking fuel drip by drip underneath the passenger side of the intake towards the front. I opened the cap to let the pressure out and it stopped….for a little while but now it’s at it again. Im thinking the FPR is the culprit but if that is the case then I’m also thinking there might be fuel in the air intake, oil, engine and other places it’s not supposed to be. I’m gonna unplug the battery completely so no sparky happens….any tips would be very helpful. I think about the engine flush, changing oil filter and then avoiding being blown to smithereens and I’m starting to feel intimidated….any help 😔?

ajp01

If your FPR is the original, then it very likely needs replacement. Mine was toast 4 years ago, same age car. Smart move to disconnect the battery. Your description of where the leak is located is hard to understand, but if you've got liquid dripping from an intake plenum or runner area then yes the regulator is a prime suspect.

Remove the vacuum line hose from the top of the regulator and see if you've got liquid fuel or strong fuel smell there. If there's fuel in that line, there's the source of fuel into the air intake tract.

Don't crank the motor, because you could hydrolock it. Recommend you remove the spark plugs to let any potential fuel evaporate off, check the oil to see if it has fuel in it. If it does, change the oil and do the fuel pressure regulator anyway. The parts to rebuild it are not that expensive, but it takes labor time. Look up the procedures and make sure you have replacement gaskets and O-rings if you're removing fuel system seals. Good luck.

Faceman89

Forum member ajp01 gave perfect advice. The FPR isn’t overly difficult. You can do it without removing the runners. Unbolt the plenum and TB and lift off. Be very careful removing the screws holding the lid on, you don’t want one breaking off…..ask me how i know 😒.

id definitely consider an oil change if you feel It was that bad.

Sonia_Blades

Yea this is what it’s looking like under the car, the stain is under the intake and runs the whole length of it. Any ideas…could it be something else?

The picture I was taken from in between the passenger side tires facing the front driver tire.

Sonia_Blades

And this is where I see the leak coming from, in between the headers on the passenger side.

Sonia_Blades

Sorry for all the responses guys I’m learning new things as I stand here and look at this thing so the drip drip drip is at the end of the driver side fuel rail towards the front and all the wiring has gas on it and now I’m just like bro there’s fuel everywhere like at this point, I’m just gonna call my mechanic. But if anyone is in the know on anything else that it could be other than the fuel pressure regulator, please let me know.

ajp01

Did you check that vacuum hose from the FPR to see if it contains fuel or vapor? That looks like the right location for fuel to have come from that line, into the top plenum, then down the runners to the intake manifold area. I also would not rule out that the #4 injector nearby may be leaking from the top O-ring in the fuel rail itself based on what I see in the photo. But start with the FPR vacuum hose check, and rebuild the FPR for sure anyway.

ajp01

Based on your later post #6 above, the safest bet is probably rebuild the FPR and replace all the O-rings in the fuel rail and injectors as well. Do it yourself and you're looking at $200 parts cost. Take it to a shop and you're looking at about $1K considering labor time cost.

Sonia_Blades

Okay, so any recommendations on parts?

Sonia_Blades

Btw Burning Brakes you have been more than helpful! That explanation sounds right on point! Now for the parts lol.

ajp01

https://fuelinjectorconnection.com/c...and-spring-kit
https://fuelinjectorconnection.com/c...ith-viton-seal
Fuel Rail O-rings you can probably get at your local GM dealer, Napa, Autozone, etc.....