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348 make it the best

up by the heater matrix, you have to take the front trunk lining out, are a few fuses and relays. there is a 30amp one that can cause trouble; but i cant recall if its solely for the heater/ fan or does something else! but its one that not many know about
1. All fuses checked-OK
2. All relays checked-OK (all over the car)
3. There is a spark for both banks
4. The voltage checked for coils and ignition amplifier, maf, throttle positions sensors
5. There is no fuel pump sound while turn the key. I can manually run the pumps with direct +12v. Both pumps are ok, but I don't know if the pumps are kicked together with starter.
6. The spark plugs for right bank seams to be more wet than for left side. Left bank spark colour is perfect. Maybe I was driving only with 4 cylinders, that is why there was no full power, but the engine works really smooth.

What comes to my mind is
1. Crank or camshaft position sensor
2. Fuel pressure sensor (it that is installed on 348).
3. Need to dig some info how to blink the failure codes, maybe that will guide more.
 
you can jump the fuel pumps at the relay; cant recal exactly how, sorry. do you get power at the fuse panel in the footwell?

if that doesn’t show any faults, id suggest its chasing the ignition wiring. as both banks are almost separate systems, id be chasing the power from battery/fuse panel/ignition/ecus.
 
you can jump the fuel pumps at the relay; cant recal exactly how, sorry. do you get power at the fuse panel in the footwell?

if that doesn’t show any faults, id suggest its chasing the ignition wiring. as both banks are almost separate systems, id be chasing the power from battery/fuse panel/ignition/ecus.

I have kicked the fuel pumps at the relays - both works. There is a power at the fuse panel as well. I have even try kicking fuel pump manually and starting the engine - does not work. It is strange, as there is a spark, pumps were started manually, so the car should run. I will check today the power to ECU and try to blik the codes.
I think there might be a problem with fuel pressure. Need to check that later on.

When I picked up the car from workshop, I was told, that sometimes the fuel regulator stuck, and I need to crack longer to start the engine. Need to check that.
 
I'd check the MAFs and Throttle Position Sensors first. Check the connections on all of them are good (bit of contact cleaner never hurts) and check you're getting the correct resistance across the MAFs.

checked, and everything seems to be OK. right- 385Ohm; left- 387Ohm

Seems I'm going into good direction :)

I have checked, and both ECUs and fuel pumps are correctly kicked by ignition/ starter. It strange, that the fuel pumps are getting +12V only when the starter is running. There is no +12V only with the key ignition.


Yesterday, I have taken of the vacuum lines from the fuel pressure regulators. The engine does not start, but there was “one or two ignitions”. That means The fuel pressure issue. Today I should get the equipment to measure the fuel pressure to check if the regulators are broken or the pumps.
 
if it is fuel pressure might also be gummed up pumps from the rubber components as they degrade with age, common issue with these.

but real coincidence if both sides went at the same time!

pic of mine when i did them. horrible job!
 

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if it is fuel pressure might also be gummed up pumps from the rubber components as they degrade with age, common issue with these.

but real coincidence if both sides went at the same time!

pic of mine when i did them. horrible job!
indeed, that is possible option as well.
Today I have measured the fuel pressure, and it looks, that regulators can be ok. Left pump cant't build the pressure, but there is a flow. Right pump- no pressure, no flow.


 
Now, everything is clear. Removing the fuel pump is quite easy but dirty job. Pumps, filters, rubber isolators were replaced 2 years ago, so perfect condition. Don't know why for both pumps the fuel hoses becomes loose, and there was no pressure no flow.
Orgering new hoses, antivibration gasket (it is the right time), tidying up the electric cables, and should work.

IMG_4004.jpegIMG_4003.jpeg
 
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hateful job removing the pumps; but great news you found the problem; very odd one that!
it is strange, but I think I found the root cause.
About 2 years ago the company which help me to get the car from Switzerland to Poland replace the fuel pumps During that job the feed and return fuel lines were replaced (just the section inside the tank. As you can see on the pictures there were some ties to hold the lines in place.
Original line is 6mm, and the lines which was installed were 8mm. The connection with bunjo bolt was a bit loose and with the fuel pressure it fell off.
Ok, I have ordered new feed lines, new orings and new vibration isolator.
Unfortunately the return line is not available, and I was not able to find anywhere. I was trying to find some connector for thread M10x1,25, but was not able to, so I decided to machine original connectors.

IMG_4017.jpeg
With that I was able to fit the house 8*1mm. I used the PA12 hoses for compressed air which can work with gasoline.
IMG_4018.jpeg
New isolators, and finally new fuel feed line.
IMG_4015.jpeg IMG_4016.jpeg IMG_4019.jpeg
And.... What the hell...!!?? New feed line, extremely expensive feed lines are tho short!!! 150£ spend to get the plastic connector, grrr.
I cut the original lines to get the plastic connector and the banjo.
To be continue ;)
 
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