Cutlass issues... again. FIXED

[nebojsa_o]

Yeah, I'll see if I can get it tested somehow, but either way, the "fixing" will have to wait until after July 1st. I'm leaving Canada on May 31st, and going back to Croatia for a visit for a whole month. I haven't been back since I moved here 11 years ago. So when I get back I can work on that while looking for a new job.

[nebojsa_o]

Hey all. Yes this is a old post, but it's mine, and it's for the same issue.

 

Ok, so I bought a fuel pressure guage yesterday, and tested it. Key On Engine Off, the guage shows 28 PSI, and when started, pretty much no change... Which is low, correct?

 

The fuel filter is only a few months old, and has probably less than 1000 miles on it. Is it possible it's the FPR, or should I just go ahead and replace the fuel pump? I tried removing the hose from the FPR to see if there was fuel in it, and there wasn't. From what I was told on here, everything points to a bad fuel pump, and now with confired low pressure I'm pretty sure that's it. Just basically asking if I should bother with anything else, or should I go drop the tank?

[nebojsa_o]

Hey all. Yes this is a old post, but it's mine, and it's for the same issue.

 

Ok, so I bought a fuel pressure guage yesterday, and tested it. Key On Engine Off, the guage shows 28 PSI, and when started, pretty much no change... Which is low, correct?

 

The fuel filter is only a few months old, and has probably less than 1000 miles on it. Is it possible it's the FPR, or should I just go ahead and replace the fuel pump? I tried removing the hose from the FPR to see if there was fuel in it, and there wasn't. From what I was told on here, everything points to a bad fuel pump, and now with confired low pressure I'm pretty sure that's it. Just basically asking if I should bother with anything else, or should I go drop the tank?

[RobertISaar]

key on, engine off, you should see ~43.5PSI. with the engine running at idle, is should drop a few PSI, but less than mid 30s would be a cause for concern.

 

if it STAYS at 28PSI wether running or not, that points to the FPR. if the pump couldn't flow it, there would be significant drop. i would look to the FPR.

[nebojsa_o]

Well, I was just out there again. Key on, engine off was 20 PSI, and when I started it, it went to 28 PSI... Does that make any sense?

[RobertISaar]

WTF?

 

are you forcing the motor on during the reading? or are you reading it after the pump stops after the 2 second run?

[nebojsa_o]

Hook up the guage, put the key in, turn it to ON position, and let the pump do its thing, leave the key in ON position and walk out of the car and look at the guage... Then back in the car, and crank it, and then back out to look at the guage. Please don't tell me I managed to do that wrong too? Yeah, I was really suprised by todays numbers too...

[RobertISaar]

if you have someone else to look at the guage, or can force the pump to run continuously with the engine off(jumping the relay should work), you really need to see what the pump holds it at with the engine off... sounds like something is leaking down by the time you get out and check the guage.

[nebojsa_o]

I was just out there again with my dad. I looked at the guage while he did the key turning. From off to ON position, the pressure goes from 0 to about 18 PSI on the guage, and stays steady. When he starts the car, it climbs to 26-29 PSI and levels off at about 28 PSI.

[RobertISaar]

 

something is incredibly wrong here...

 

because it's doing the exact opposite of what it should be....

 

i still want to say regulator though, unless the fuel pump is REALLY benefitting from the extra voltage the alt provides when the engine is running, compared to sitting with the engine off.

 

interesting thought to test this: jumper cables from one vehicle to another to get the benefit of increased voltage without changing other conditions on the vehicle. if the pressure then goes to ~28PSI engine off, then your problems lie in either the pump itself, or it's wiring.

[nebojsa_o]

That's an interesting idea. I might give it a try tomorrow when my brother is back in town. I'm really surprised by the difference in pressure from yesterday and today. And it starts and actually runs just fine, it's not even doing the sputtering thing...

[nebojsa_o]

So I tested it today, and the pressure is the same as yesterday. 18 PSI engine off, and 28 PSI when running. I went to a junkyard, grabbed a FPR, and replaced mine. And it's exactly the same. I guess I could check/replace the fuel filter even though it's new (maybe it fell apart on the inside?) and the next step is the fuel pump.

[GnatGoSplat]

Sounds like fuel pump to me. You could dead-heading the pump by squeezing the return line and see if you build up more pressure. I think a dead-headed pump should build up >60psi easily.

Replacing the filter couldn't hurt, but I doubt that's going to be it.

[nebojsa_o]

Yeah, I doubt it's the filter... Phuck it, I'm replacing the fuel pump. Just need to figure out what to go with. I have access to AC Delco, Delphi, and AAC Airtex or something like that in town here. Don't know if anyone has Bosch in town, but I'll call a couple more places. Delphi is the cheapest at $112, and I've read they're good, but I have no idea... Any recommendations?

 

EDIT: Just found Bosch in town for $133.

Edited August 3, 2010 by nebojsa_o

[GnatGoSplat]

I'd actually recommend Walbro 255lph high pressure pumps. I put an older design one in my 89 Cutlass and a newer design one in the 90 TGP. They are super quiet and < $100 shipped from an eBay. They work fine with a stock engine and have plenty of capacity for any mods you might dream up.

[nebojsa_o]

I already got the Bosch... I'm probably dropping the tank tomorrow, and depending on how it goes, and how much time I have, I might do the whole job tomorrow. It comes with some sort of instructions and they mention something about a fuel pulsator or something like that, and how the new pump doesn't need that, so you can discard it. No clue what that is, but I guess I'll see tomorrow.

[GnatGoSplat]

I personally dislike Bosch. They have typically been the least reliable parts I've ever put on my car, so I avoid them. Bosch is also very commonly used on German cars and it doesn't surprise me that they are the least reliable cars you can buy.

 

Fuel pulsator is a little plastic box with a stamped steel cover on it attached to the end of the fuel pump. It's supposed to make the fuel pump quieter. You should be able to replace it with a short piece of rubber hose which probably came with the pump. I bought a new pulsator for my 89 Cutlass, but used the hose on the TGP. I don't really notice that much difference. Pulsators are pricey and you wouldn't want to reuse the old one anyway, so I say lose it.

[nebojsa_o]

Does a '96 Cutlass 3100 have the fuel pump test lead wire somewhere? I couldn't find mine, and I know where it's supposed to be... I ended up dropping the tank, and siphoning out about 16 or 17 liters. There is still some in there, but I'm not having much luck getting it out. Either way, it's not a lot...

 

What would be a good way to clean the fuel tank once I have the pump out? Any special products I should use for that? Or just water, and let it dry for a while? Any tips?

[RobertISaar]

the test lead was OBD1 only IIRC... you could have jumped the relay though, that would have powered the pump.

[nebojsa_o]

Yeah, I just gave up after I didn't find the test lead, and did it how I was gonna do it originally. But yeah, I was asking about the test lead to confirm if it did exist in '96 (OBD2). Sure looks like it didn't.

[RobertISaar]

yeah, i just looked up the diagrams, OBD1/1.5 only

[GnatGoSplat]

Does a '96 Cutlass 3100 have the fuel pump test lead wire somewhere? I couldn't find mine, and I know where it's supposed to be... I ended up dropping the tank, and siphoning out about 16 or 17 liters. There is still some in there, but I'm not having much luck getting it out. Either way, it's not a lot...

 

What would be a good way to clean the fuel tank once I have the pump out? Any special products I should use for that? Or just water, and let it dry for a while? Any tips?

 

If it's not a lot and not too heavy for you to deal with, I'd just leave the fuel in there and avoid any sources of spark or ignition!

Why do you need to clean the fuel tank? I've never had one that was dirty inside, and I've changed 5 so far. I personally would not clean it if there's no specific reason. I don't think water in a fuel tank is a very good idea.

[nebojsa_o]

Yeah, I didn't think so either, that's why I asked about any products for that sort of use. I thought I should clean it up because I saw people talking about that online, and I was told that by the guy at the place when I bought the fuel pump... If it's clean I sure as shit won't rinse it with water or anything, but some people made it sound like I'll find all sorts of little shit on the inside. Good to hear usually they are clean on the inside.

 

EDIT: A bit of a update I guess. I got the pump out, swapped the stuff around, and put the new one back in. I reused the original big ass O-ring since it was in great shape, and the new one didn't seem to be as good, and was quite thick, and slightly "warped" so it was a bitch to line up. The tank was just like you said, looked perfectly nice and clean, I was expecting a nightmare for some reason.

 

I have a funeral to go to in the morning (R.I.P. Hans Bielefeld), and after that I will probably put the tank back up, and hope everything works like planned.

Edited August 5, 2010 by nebojsa_o

[nebojsa_o]

So yeah, I put the tank up earlier today. The car started up fine, and I tested the fuel pressure, and with key on, engine off, it sits at 44 PSI, and when started it drops to 40 PSI. So all is well for now. Thanks for all the help, and advice guys.

[GnatGoSplat]

Woohoo! I'm glad you got it fixed. I'm sorry to hear about the death of your friend though.