V70 Steel Tank Long Crank Fixed

chancejack · Post by **chancejack** » 18 Mar 2020, 23:15

Ok just want to share an experience of how did I fix my V70 w a steel tank, long crank problem.

Year: 2004 V70 w 70k miles
Symptom: Special in the morning cold start, Long crank, need to press the gas peddle to help to start.
Diagnosis: Use fuel pressure gauge, prime the fuel couple time, found out : the fuel pressure drop quickly.
After look at many information online, so this is could be the check valve at the fuel pump went bad. Ok, but this is a painful steel tank, it is so hard to get on the fuel pump, it is not worthy to get a 200 dollar fuel pump for the check valve which cost me about 10 dollar.

Tips may help others:
1. the location I choose to add a after market check valve is the under the passenger side wheel. Use quick disconnect tool disconnect the fuel line.
2. Do not , Do not use the ball check valve,

I tried this first, and it failed.

You need to use spring type check valve.

other than this you may need a connector:

So the size of the fuel line connector is 5/16" 9mm .
Hope this can help.

chancejack · Post by **chancejack** » 18 Mar 2020, 23:23

Here is the photos

Post by **darrylrobert** » 19 Mar 2020, 02:10

thanks where did you source the valve from?..problem with trying to repair the intank check valve is removing the valve (think its molded in the plastic?) second is buying a replacement, i emailed bosch 1 week ago and no reply.

Post by **oragex** » 19 Mar 2020, 03:21

I wonder if the original topic has properly diagnosed the issue. Most garages look at the fuel pump because many import and domestic cars have problem with their fuel pumps, but on these Volvo cars the fuel pump is very rarely at fault, even on cars with very high miles. Most probably the problem is either with the fuel pump module PEM or pressure sensor FPS, on cars from 2003up. With fuel pressure dropping quickly, possibly the FPS is leaking internally. Easy to replace, but careful not to strip the small bolt, and to release the fuel pressure at the shredder valve and work on a cold engine.

chancejack · Post by **chancejack** » 23 Mar 2020, 20:14

@ darrylrobert
Thank you for your interest on my thread. Well, I would say I admire you very much, I didn't have the courage or skill to try to get into the pump. So first of, how I diagnosis my issue? From my symptom: not just long crank but when I press the pedal gently it will helps. Besides, once it started, it runs really smooth no issue at all, so I rutted out the PEM and fuel pressure sensors issue. IF those two had issue, when I tried to accelerate hard, I will notice it. Secondly, by the fuel pressure gauge. It can prim the fuel by turning key, but can't hold it. which tells us there is a internal leak somewhere that caused it can't hold the pressure. So there is two possible, the check valve or the injector. Of course, let us try the easier one first. So I put in a check valve.

@ darrylrobert : I didn't take the pump out. I just find the section of the fuel supply line that has the quick connector, it is under the passenger side, near the right front wheel. Ok , yours is the plastic tank, that will be even easier. Your will find your fuel filter easily, right? near the right rear wheel? so put the check valve before or after the fuel filter. Let me know you have any further questions.

Post by **darrylrobert** » 23 Mar 2020, 21:02

thanks, if you have "fixed" the problem installing your own one way valve that is great, however i personally would be finding the real problem and fixing it. At first i thought adding a one way valve was a great idea but if an injector is leaking then its not going to fix the problem and you are changing the design of the fuel system, for safety its designed NOT to hold pressure above 3.8bar, you really need to add an inline one way pressure valve. Good luck

chancejack · Post by **chancejack** » 15 Oct 2020, 06:31

Yes @ darrylrobert is right, my add on check valve blast out the fuel line. Later one website said this kind of one way valve only can apply to return fuel system. Do do this. It could cause big accident catch fire and burn the car

chancejack · Post by **chancejack** » 02 Jan 2021, 15:28

So some update. I removed the check valve. And put a straight hose on the section I disconnect. Why? because the Barb to bundy connector I can't take it off. So I have to leave it there. After a while I check the fuel hose, the auto zone fuel hose. It was cracking. After so much research, I found out, fuel hose have two kinds : carbonator hose and injection hose. If you don't ask specifically, the autozone will give you the carbonator hose which handles maximum 50 psi. The volvo runs around 55 psi on idle. So after a while , of course, the fuel hose crack. You need to go to Napa to get injection hose. You also need to use fuel hose clamp instead of worm clamp. The fuel injector hose can handle maximum 225 psi. So I put every back together, just use the right hose this time. It works so far so good.

chancejack · Post by **chancejack** » 05 Jan 2021, 21:41

Update: No, the quantum check valve won't work, it created too much pressure. So I had to take it out. Well, the long crank it is crank twice , each time about 2s not too bad. this is cold start, once warm it is one time crank

chancejack · Post by **chancejack** » 03 Sep 2021, 21:31

So more update. Because of long crank time, finally I damaged the ring gear.

I got to sperate the tranny and engine replace the ring gear. Well, during this process I replaced the subframe bushing. Use the youtube volvo pepermint method, very good, about 20 mins per one bushing.
ok, after I put everything back together. I forgot to tight up the pipe and the throttle body.
So I can start the engine but then die because the huge vacuum leak.
During this period, I noticed that every time I started cranking the engine, it came right up. No issue at all. so the fuel pump isn't the problem?
I need to further verify is there somewhere in the intake path has a issue, it is not fuel but the air issue.