Wrenchin... Adventures under the hood... Put em here.

[MontuckyFried]

This is a 2008 Saab 9-5...

Well, there's your problem, mister.

Sorry. Couldn't help myself.

[El Chupacabra]

I didn't think fuel pumps had any sort of drainback valve. Fuel pressure regulator, yes, but that's not to prevent drainback.

Could it be something else related to the gas tank, such as emissions system (charcoal canister), or vent tubing?

Obviously I am no expert on Saabs...

[Skidog]

Quick question to folks that really know fuel systems. It appears that my backflow valve at the fuel pump is not working correctly allowing fuel to drain back to the tank when it sits for kind periods (over 7-8 hours). The result is a first cold start sputter then dies. Second crank starts the car just fine. Fuel pump replacement requires a tank drop and fuel pump is fairly expensive for OEM.
I have measured with a fuel pressure gauge at the rail and it shows good pressure once it starts. Am I causing any further damage by using the start twice method when cold ? I will also try turning the key to position 2 multiple times to build pressure before start.
The hard part of the diagnosis is I only get one or two tries a day to assess the problem since it needs to be a first cold start.
This is a 2008 Saab 9-5 with 155k miles.

you know...this is going to sound fucking WAY out there, but I had some fuel issues with the exact same year and model (wagon), and my Utah mechanic said...run Chevron premium gas for a while....I laughed and did it anyway....amazingly enough...it fixed the issue. Might not work in your case but it sure is easy enough to attempt.

[The Reverend Floater]

Quick question to folks that really know fuel systems. It appears that my backflow valve at the fuel pump is not working correctly allowing fuel to drain back to the tank when it sits for kind periods (over 7-8 hours). The result is a first cold start sputter then dies. Second crank starts the car just fine. Fuel pump replacement requires a tank drop and fuel pump is fairly expensive for OEM.
I have measured with a fuel pressure gauge at the rail and it shows good pressure once it starts. Am I causing any further damage by using the start twice method when cold ? I will also try turning the key to position 2 multiple times to build pressure before start.
The hard part of the diagnosis is I only get one or two tries a day to assess the problem since it needs to be a first cold start.
This is a 2008 Saab 9-5 with 155k miles.

My unqualified opinion is to prime the pump pressure via your second method before turning it over as to not wear out your starter. But it sounds like you have a pump issue. Is the voltage to the pump adequate?

Does it matter if you give it some throttle?

[fatnslow]

you know...this is going to sound fucking WAY out there, but I had some fuel issues with the exact same year and model (wagon), and my Utah mechanic said...run Chevron premium gas for a while....I laughed and did it anyway....amazingly enough...it fixed the issue. Might not work in your case but it sure is easy enough to attempt.

Not out there at all it's all over the forums especially about winter/summer fuel switch. I just filled with Costco yesterday hoping it's a "top tier" gas, next tank I'll try Chevron. Same problem this morning so my plan is trying the twice prime tomorrow morning.
There definitely is a check valve in this system, it's actually a fairly common component on fuel injected cars. Nobody thinks about it until it fails and starts weird issues.

[fatnslow]

My unqualified opinion is to prime the pump pressure via your second method before turning it over as to not wear out your starter. But it sounds like you have a pump issue. Is the voltage to the pump adequate?

Does it matter if you give it some throttle?

Haven't actually checked voltage at the pump but it is turning and i also threw in a different fuel pump relay, fuel pressure regulator and coolant temp sensor. Throttle movement doesn't change the sputtering. the hardest part of troubleshooting is I only get one shot a day if i drive it. It's just a nusance and as skidog stated these have been known to be picky about gas when they switch seasonal fuel. I'm one a different fill up than usual so I'll see if there are any changes. It's my wife's car and doesn't get driven much so my plan is to drive it for the next few weeks and see if a couple tanks of gas makes a differnce. Once it starts it drives fine and restarts just fine for the rest of the day.

[Skidog]

Not out there at all it's all over the forums especially about winter/summer fuel switch. I just filled with Costco yesterday hoping it's a "top tier" gas, next tank I'll try Chevron. Same problem this morning so my plan is trying the twice prime tomorrow morning.
There definitely is a check valve in this system, it's actually a fairly common component on fuel injected cars. Nobody thinks about it until it fails and starts weird issues.

my utah mech also mentioned the summer/winter switch....interesting to hear its on forums. Worth a shot anyway..

[fatnslow]

my utah mech also mentioned the summer/winter switch....interesting to hear its on forums. Worth a shot anyway..

at least the price is right

[fatnslow]

Well, there's your problem, mister.

Sorry. Couldn't help myself.

Well, it's no Audi ! 08 with 155k needing a bit of love is to be expected, even my Honda is about the same attention seeking at similar age/miles.

[MontuckyFried]

Well, it's no Audi ! 08 with 155k needing a bit of love is to be expected, even my Honda is about the same attention seeking at similar age/miles.

Haha. Touche! Yup. Simply being an Audi of advanced age is EXACTLY the problem with this old POS. I have a real love/hate relationship with the A4. Love the way it drives/handles. Hate everything mechanical about it.

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[powdrhound]

The Chevron addictive is Techron.
Also available by the bottle at your local parts house.
It does a great job of cleaning sticky injectors (probably the bottom line problem).

[basinbeater]

Second... Techron is good stuff. In fact, I should probably get a couple bottles and run them through my old bimmers.

sent from Utah.

[Skidog]

The Chevron addictive is Techron.
Also available by the bottle at your local parts house.
It does a great job of cleaning sticky injectors (probably the bottom line problem).

i didnt guess that was what the difference was, but i know they all add their "magic" additives.

[highangle]

They change diesel summer to winter, but refineries don't change gasoline formulation by season. They may have seasonal minimums on the amount of ethanol they have to blend in your state or county, but you should state that when you casually mention winter/summer gas like it was some kind of Chain Stretcher [Audi owner] belief system.

[Thaleia]

So my hitch mounted Thule bike rack rack failed last week (it's the type that can pivot down at the base to allow for trunk access. It pivoted down while driving, thankfully was not on the highway when it happened)

Attempted to take the rack off the hitch and the bolt that secures it was seized. Sprayed the hell out of it with PB Blaster for the next 24 hours. Tried again and the head of the bolt sheared off.

I've seen online people recommending to weld a bolt head or grind a slot and use a screw driver to remove the bolt but given how seized it is I doubt those would work.

I tried drilling through the bolt but after about an hour I had only made a 1 or 2 mm dent in it.

Guess I have to take the hitch off the car but am now worried the four bolts securing the hitch assembly to my car could be seized and I get a similar result as above.

Anyone deal with something like this? Feel kind of stuck on this one.

[anotherVTskibum]

So my hitch mounted Thule bike rack rack failed last week (it's the type that can pivot down at the base to allow for trunk access. It pivoted down while driving, thankfully was not on the highway when it happened)

Attempted to take the rack off the hitch and the bolt that secures it was seized. Sprayed the hell out of it with PB Blaster for the next 24 hours. Tried again and the head of the bolt sheared off.

I've seen online people recommending to weld a bolt head or grind a slot and use a screw driver to remove the bolt but given how seized it is I doubt those would work.

I tried drilling through the bolt but after about an hour I had only made a 1 or 2 mm dent in it.

Guess I have to take the hitch off the car but am now worried the four bolts securing the hitch assembly to my car could be seized and I get a similar result as above.

Anyone deal with something like this? Feel kind of stuck on this one.

Is the bolt in place of the pin that normally holds the tongue and ball assembly into the receiver? That's a classic spot for rust welding, and I think that expecting the bolts holding the receiver to the frame to be more of a PITA is valid.

If you haven't tried applying heat to try to break the corrosion free, get a propane torch and have at it (safely, of course).

Is the bolt screwed into the rack on the other end? If it's a free nut, you could try heat and PB there, and then knock the whole thing through.

I've also had pretty good luck with hammered in extractors, eg https://www.lowes.com/pd/CRAFTSMAN-5...Set/1000594887

Those may or may not be the best sizes for you (or even the best extractors), but something of that nature. You will need to manage to drill a centered hole first, though, so starting with a punch and then a small bit and working up has been my strategy. Also, if you're not using a fresh, high-quality drill bit intended for metal work, I'd get one (and use a decent corded drill unless you have a really good cordless).

But at the end of the day, I'd be really tempted to try to pawn that off on a trusted local mechanic. They have all of the above tricks and more, and I can cover the cost of doing so in the hours I can actually work because I'm not cussing road salt in the garage.

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[powdrhound]

They change diesel summer to winter, but refineries don't change gasoline formulation by season. They may have seasonal minimums on the amount of ethanol they have to blend in your state or county, but you should state that when you casually mention winter/summer gas like it was some kind of Chain Stretcher [Audi owner] belief system.

Maybe the rest of the world doesn’t change gas formulas for winter.

But California? Sure, we do.

[MakersTeleMark]

Problem #1: rig a simple 12v fuel pump on the frame rail rigged to a switch in the cab to use for priming;
Problem #2: use a grinder.

[Thaleia]

Is the bolt in place of the pin that normally holds the tongue and ball assembly into the receiver? That's a classic spot for rust welding, and I think that expecting the bolts holding the receiver to the frame to be more of a PITA is valid.

If you haven't tried applying heat to try to break the corrosion free, get a propane torch and have at it (safely, of course).

Is the bolt screwed into the rack on the other end? If it's a free nut, you could try heat and PB there, and then knock the whole thing through.

I've also had pretty good luck with hammered in extractors, eg https://www.lowes.com/pd/CRAFTSMAN-5...Set/1000594887

Those may or may not be the best sizes for you (or even the best extractors), but something of that nature. You will need to manage to drill a centered hole first, though, so starting with a punch and then a small bit and working up has been my strategy. Also, if you're not using a fresh, high-quality drill bit intended for metal work, I'd get one (and use a decent corded drill unless you have a really good cordless).

But at the end of the day, I'd be really tempted to try to pawn that off on a trusted local mechanic. They have all of the above tricks and more, and I can cover the cost of doing so in the hours I can actually work because I'm not cussing road salt in the garage.

Sent from my SM-G892A using TGR Forums mobile app

Hey thanks for the advice, it is greatly appreciated.

Yes, bolt is in place of a pin. It must thread into the bike rack since there is no nut on the opposite side.



This is the sheared off side, no nut on the other side.

I know those extractors a little too well - given how 'stuck' it is I can't see it working with my skill level.

I'm thinking of two options at this point - mechanic to remove all, or maybe spend some time with a grinder (thanks MTM) and cut the bike rack portion off which will allow me to possibly see if I can then get at the bolt from the inside of the carrier.

[MontuckyFried]

Hey thanks for the advice, it is greatly appreciated.

Yes, bolt is in place of a pin. It must thread into the bike rack since there is no nut on the opposite side.



This is the sheared off side, no nut on the other side.

I know those extractors a little too well - given how 'stuck' it is I can't see it working with my skill level.

I'm thinking of two options at this point - mechanic to remove all, or maybe spend some time with a grinder (thanks MTM) and cut the bike rack portion off which will allow me to possibly see if I can then get at the bolt from the inside of the carrier.

Is that bolt threaded all the way through or just at the end? You tried whacking it with a big nail punch and a small sledge?

[snowaddict91]

Hey thanks for the advice, it is greatly appreciated.

Yes, bolt is in place of a pin. It must thread into the bike rack since there is no nut on the opposite side.



This is the sheared off side, no nut on the other side.

I know those extractors a little too well - given how 'stuck' it is I can't see it working with my skill level.

I'm thinking of two options at this point - mechanic to remove all, or maybe spend some time with a grinder (thanks MTM) and cut the bike rack portion off which will allow me to possibly see if I can then get at the bolt from the inside of the carrier.

Since it sounds like the rack is trash, I'd say you should get that pin ground/drilled down to where it is no longer stopping the rack, then tie a strap to the rack to something strong and attempt to pull it off. Carefully of course. If you cut the rack at the hitch tube I bet you'll never get the remains out of your hitch.

[fatnslow]

Problem #1: rig a simple 12v fuel pump on the frame rail rigged to a switch in the cab to use for priming;
Problem #2: use a grinder.

I do have an angle grinder so maybe I can just use it to cut my fuel line to add that auxiliary fuel pump ? I don't think pumps do too well pulling up hill in the engine bay near the fuel rail. I have been looking at where/how to add an external check valve near the fuel pump/tank area but the hard plastic lines are not too friendly to such hacks.

[MakersTeleMark]

I do have an angle grinder so maybe I can just use it to cut my fuel line to add that auxiliary fuel pump ? I don't think pumps do too well pulling up hill in the engine bay near the fuel rail. I have been looking at where/how to add an external check valve near the fuel pump/tank area but the hard plastic lines are not too friendly to such hacks.

You really are slow.

[The Reverend Floater]

I do have an angle grinder so maybe I can just use it to cut my fuel line to add that auxiliary fuel pump ? I don't think pumps do too well pulling up hill in the engine bay near the fuel rail. I have been looking at where/how to add an external check valve near the fuel pump/tank area but the hard plastic lines are not too friendly to such hacks.

Angle grinder + fuel line = Bad Idea Jeans

[powdrhound]

Angle grinder + fuel line = Bad Idea Jeans

If his camera is running it could make for a viral video.