308 QV EURO hesitates to fire up after sitting several days. Fuel Filter sweating fuel from housing | FerrariChat
Buy

308 QV EURO hesitates to fire up after sitting several days. Fuel Filter sweating fuel from housing

Discussion in '308/328' started by Jerry458, Jul 21, 2025 at 6:06 PM.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, Skimlinks, and others.

  1. Jerry458

    Jerry458 Karting

    Nov 6, 2024
    90
    NYC
    #1 Jerry458, Jul 21, 2025 at 6:06 PM
    this hesitation has been happening for a while if i let the car sit for a week it seems the fuel pressure is bleeding out and the car takes forever to pressurize and fire up. If I start the car and run the car it fires up instantly day after day always up until it sits for a week without being used.

    Today I was looking down at the fuel pump/filter for any leaks and I see fuel varnish residue on the top area of the fuel filter where the housing is crimped. Looks like oil but it is 100% gasoline. I checked the hard line going into the top of the fuel filter and it is not loose. I have the correct smaller EURO fuel filter as well. I wiped the residue and let the car idle for ten minutes and the area had more fuel residue on that lip, see photo. I am going to order a new fuel filter ASAP as maybe this is where the system is loosing pressure over time, looks like a bad crimped fuel filter because I see no fluid travel or residue from where the center line connects it appears to be sweating at the crimp area only. I got this fuel filter from Mr Fiat off ebay last year the fuel pump and accumulator were both replaced with OE Bosch units last year from AW. I do not know for sure if the fuel pump I bought has the internal non return check valve or not but the fuel pump does not have that black plastic sleeve over it to fit the clamp it is an OE housing and these are tough to get now I hear.

    Anyone have suggestions on this symptom on what else to check out? Does the fuel pump check valve cause these forever crank issues when sitting and do these check valve go bad?

    Image Unavailable, Please Login
     
  2. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    26,799
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #2 Steve Magnusson, Jul 21, 2025 at 6:14 PM
    Yes, but a bad check valve can't cause a difficult start-up after a week, but the car starts fine after sitting overnight. Post a picture of the front of your fuel pump -- it should be fairly easy to determine if it has a check valve or not.
     
  3. Jerry458

    Jerry458 Karting

    Nov 6, 2024
    90
    NYC
    #3 Jerry458, Jul 21, 2025 at 6:36 PM
    will try my best tomorrow if I can get my phone from the top to get a good view otherwise il go from the bottom up.
     
  4. Sergio Tavares

    Sergio Tavares Formula 3

    Nov 15, 2018
    1,308
    Full Name:
    Sergio Tavares
    #4 Sergio Tavares, Jul 21, 2025 at 7:41 PM
    Please to read the Mr. Fiat reviews make it seem there are no parts and he drop shipped everything from real suppliers
     
  5. Jerry458

    Jerry458 Karting

    Nov 6, 2024
    90
    NYC
    #5 Jerry458, Jul 23, 2025 at 11:52 AM
    Hi Steve here is a photo of the pump and accumulator, the braided line from the accumulator that attaches to the bottom of the fuel filter is pretty crushed it seems so i just ordered a replacement #119278. Car still struggles to fire up I pulled the easier to get to crank sensor and it was a bit dirty and greasy I may need to explore all 3 now when i get time as a culprit. The fuel residue on the filter still has me scratching my head as the line is so tight it doesn't budge.
    Image Unavailable, Please Login
     
  6. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    26,799
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #6 Steve Magnusson, Jul 23, 2025 at 12:06 PM
    Well, that's I first. It looks like you might have two check valves in series. The pump has the longer outlet nose (where the built-in check valve usually lives), and the line with the banjo fitting goes over the external screw-in check valve. Of course, what's inside both is not certain so you should really measure the fuel pressure after warm engine shutoff to confirm/deny if you have a check valve problem or not -- should stay something like 3 bar for 20 minutes after warm engine shutoff (and the "bump" on the Accumulator being shifted forward past the band clamp shows the Accumulator has been moved forward due to the longer nose on the fuel pump). However, even with no check valve, that can't affect starting after long disuse so that's another kettle of fish IMO.
     
  7. Jerry458

    Jerry458 Karting

    Nov 6, 2024
    90
    NYC
    #7 Jerry458, Jul 23, 2025 at 3:34 PM
    Wow Steve good call from the photo I did not even see this being that it is all corroded and dirty. I had a shop in PA last July which I wont mention install the new fuel pump and accumulator and ever since they touched it the car struggled to start and their answer was bad fuel. I need to eliminate the original check valve as it looks like the pump has one internally and having two does not seem smart. It looks like they did not have knowledge with the longer pump snout.
     
  8. Jerry458

    Jerry458 Karting

    Nov 6, 2024
    90
    NYC
    #8 Jerry458, Jul 23, 2025 at 4:08 PM
    I just looked at the diagram so if you eliminate the original check valve fitting you would then need some sort of aftermarket or custom fitting to attach the hard line with the banjo end to the fuel pump but I do not see anyone offering this or mentioning this.
     
  9. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    26,799
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #9 Steve Magnusson, Jul 23, 2025 at 4:12 PM
    Certainly not necessary to have two check valves, but I don't think that alone should cause any issue. Might just be the wrong fuel pump altogether -- Bosch makes a whole rainbow of different specs in the same form factor (and it would be an additional negative if they then tried to tweak it up with something very, very wrong). IMO, you're back to where we always go when trying to sort out the CIS system on a F -- measure all the pressures, and make sure they are in spec first -- then tweak the various adjustments. Good Hunting!
     
  10. Steve Magnusson

    Steve Magnusson Two Time F1 World Champ
    Lifetime Rossa

    Jan 11, 2001
    26,799
    30°30'40" N 97°35'41" W (Texas)
    Full Name:
    Steve Magnusson
    #10 Steve Magnusson, Jul 23, 2025 at 4:15 PM
    Yes, there are two different hard line arrangements depending on the type of fuel pump:
    Internal check valve (long nose) = hollow threaded coupling and the hard line has a compression fitting on the end. This pic shows the stock internal check valve plumbing:
    Image Unavailable, Please Login

    External check valve (short nose) = hard line has banjo fitting (like your existing hard line).
     

Share This Page