Problems after fuel filter replacement

Post by **Chuck W** » 20 Sep 2019, 17:04

I guess I also missed the "month ago" part. Yes, I would expect it to adjust by now, if it was possible.

I was going to suggest an R&R of the fittings again, but you also mentioned that priming the system multiple times before trying to start the car doesn't improve things, so it seemed moot.

Have you actually put a FP gauge on it yet to verify what's happening with the pressure?

Post by **jimmy57** » 20 Sep 2019, 19:39

I have seen this a few times over the years. And it was with Volvo filters. The fuel pressure regulator gets a fibre in the seat and it leaks. The fuel drains out and there will still be air after one pump prime cycle and it takes the start n die cycle to purge the vapor. Take the line off the fuel presure regulator after yu shut off engine and see if it has a continual drip after the initial spill of fuel when line comes off. If you cycle key three times that usually will mostly fix it if this is the issue.
The speculation is that some loose filter media fibres get loose and wash off the new filter.

Post by **misha** » 21 Sep 2019, 03:05

M4.4 have small fpr near the fuel filter and have no clamps on the lines(from the factory)...i'm affraid that i will damage the lines and will not be able to put them back on fpr.
I'll post a picture later.

Post by **abscate** » 21 Sep 2019, 05:07

It might be prudent to flush the filter with the first 100 ml of fuel. You need a helper but basically just put the filter onhalfway, out open end into a cup, then keyon for a few seconds

Post by **misha** » 21 Sep 2019, 05:16

Too much hassle for little gain abscate.

Post by **erikv11** » 21 Sep 2019, 07:44

misha wrote: 21 Sep 2019, 03:05 M4.4 have small fpr near the fuel filter and have no clamps on the lines(from the factory)...i'm affraid that i will damage the lines and will not be able to put them back on fpr.
I'll post a picture later.

I agree with you to be vary careful about the hard lines. They are NLA and very difficult to remove without breaking things.

M4.4 has the small FPR near the passenger wheel or by the fuel filter. Either one is the same FPR - you can access the line by unscrewing the little clamp and lifting the FPR out of the housing.

Post by **kallekula** » 21 Sep 2019, 09:00

jimmy57 wrote: 20 Sep 2019, 19:39 I have seen this a few times over the years. And it was with Volvo filters. The fuel pressure regulator gets a fibre in the seat and it leaks. The fuel drains out and there will still be air after one pump prime cycle and it takes the start n die cycle to purge the vapor. Take the line off the fuel presure regulator after yu shut off engine and see if it has a continual drip after the initial spill of fuel when line comes off. If you cycle key three times that usually will mostly fix it if this is the issue.
The speculation is that some loose filter media fibres get loose and wash off the new filter.

I have never heard about that. Thank you for that information.

Post by **kallekula** » 21 Sep 2019, 09:03

misha wrote: 21 Sep 2019, 05:16 Too much hassle for little gain abscate.

Sounds like small hassle for possible huge gain to me.

Post by **misha** » 21 Sep 2019, 09:44

kallekula wrote: 21 Sep 2019, 09:03 Sounds like small hassle for possible huge gain to me.

It's easier to start it on the 2nd try when it sits overnight than to brake the lines trying to fix the small issue.
Than that small issue becomes a HUGE issue since the parts involved are no longer available.

Don't you think so?

Post by **kallekula** » 21 Sep 2019, 11:23

misha wrote: 21 Sep 2019, 09:44
kallekula wrote: 21 Sep 2019, 09:03 Sounds like small hassle for possible huge gain to me.
It's easier to start it on the 2nd try when it sits overnight than to brake the lines trying to fix the small issue.
Than that small issue becomes a HUGE issue since the parts involved are no longer available.

Don't you think so?

Abscate wrote that it might be a good idea to flush a new fuel filter first before you hook it up completely. I agree with that. I also believe there is little else hassle to ask a wife/buddy to turn the key for a few secs to flush the new filter using the vehicles pump as help. You are already crawling around in the dirt with rust in your eyes smelling like gas. There is little else hassle to do the flush. Am I right?

EDIT:
And the gain is huge. Avoiding some possible fibre/debree left from manufacturing enter the fuel system! HUGE!

EDIT2:
Who the hell wants a car that always starts on the second time after ditting overnight? It would drive me personally absolutely nuts. This is no problem you can accrpt and continue living with. It has yo be fixed.