sa7

iTrader: (13)

I need help trying to figure out what's wrong with my car.

First the story. I was coming home from work tonight, and my car started to feel like it was losing power, and was slowly dying. Stupid me, instead of shutting it off and pulling over, I decided to floor it and try to make it to my exit which was just in front of me. My first thought was that I had a blown apex seal. I finally pulled over just as my car was completely dying, and shut everything off. I checked my battery, my fuses, and oil. Everything seemed ok, so I tried to start it, and it just kept turning over. I couldn't hear my fuel pump start. I can normally hear my pump turn on, it's fairly loud. There was alot of traffic driving by, but I couldn't hear it. So I get my car towed home, park it in the garage, turn the key and the pump turns on. Crank it over a few times, and it started briefly, sputtered then died. I didn't try a second time.

So now that my pump has decided to turn on, what do I test or look for to find the problem? If I got home and the fuel pump still wasn't turning on, then it would have been straight forward. But now I'm not sure what I should check. Should I replace the pump, and see if it runs fine?

Sorry for the rant and for the stupid questions. I am not a mechanic by any means, but have fixed and replaced everything on the car so far. I learn as I go.

Thanks,
sa7

sa7

iTrader: (13)

I forgot to give a bit of info on the car. It's a 79, with about 57000 miles. The only mods under the hood are full exhaust with header, 2nd gen fuse box, battery in rear bins, s3 electronic ignition system, s4 alternator, e-fan, and all emissions equipment removed. Everything else is stock.

When I pulled the car out of storage, it was starting fine. But once it was warmed up, it would sputter a bit when idling. So I changed the fuel filter a few days ago, and put a can of seafoam in the tank. The day after it was already idling much better, until today.

LizardFC

iTrader: (1)

I think you're on the right track. Pumps usually die a slow death like that. An easy way to check is to look at the front sight glass after the car shuts off. If you can't see fuel, then the carb has run itself dry because the pump can't keep up.

There's a volume test you can perform on the pump to see if it's supplying the necessary amount of gas. You basically just pull the main line loose, put it down into a jug, crank for a set amount of time, and see how much gas is pumped into the jug. I can't remember the numbers or exact procedure so you'll have to search.

7aull

iTrader: (2)

-check fuel filter, which I presumed you changed 1st thing when you got the car?
-if RX has been _INcorrectly_ stored for a long time (usually with "some" gas in tank), then tank may be shedding internally, plugging up filter and/or lines from tank. Could be rust (from air space in tank and many cycles of heat/cold generating condensation in there = rust, AND/OR gunky gas residue from decades-old gas).
Mine suffered from this, esp on a LOW fuel-level. Would just die while driving. Sit a bit, start right up then die again shortly.
-solution was a tank-out cleaning at a good rad shop. they'll immerse the tank in their chem-dunk and clean it completely. Would then suggest a "liner" be added to inside. POR15 makes these tank kits. Its a liquid you slosh around the tank to seal the walls.
-79 & 80 SAs are a bit of a biotch to pull tank because NO DRAIN - so you need to pull fuel out of either the filler and/or remove the fuel sender float (which you need to do anyway to clean). I would NOT try to pull tank with much fuel as they are a real handful with fuel sloshing/weight transfer as you try to maneouver them out! Sender hole easiest way to remove fuel IMHO. Its behind a plastic panel in driver rear wheel well. YOU WILL NEED TO HAVE A NEW SENDER GASKET so have one ordered up for the install.
-finally, as you pull tank: PHOTOS!!!!!! Esp the FOUR hoses that come off the tank - VERY confusing if you mix up what goes where (don't ask how I know this...)

'luck

Stu Aull
80GS
Alaska

sa7

iTrader: (13)

I've had the car for about 5 years now. I don't know about previous owners, but I have stored it properly. I usually replace the fuel filter once a year, in the spring when I take it out of storage. I have never had issues in the past with fuel delivery. I replaced my fuel filter 3 days ago and everything was fine. I have filled my tank with new gas several times since I took it out of storage. The only new or different thing that I have done is try seafoam. I have never used it before. 7aull, you could be right though, maybe my tank had gunk in it that never caused an issue, but the seafoam broke it up. That could have clogged something up.

LizardFC

iTrader: (1)

That's a good bet, too... if you've never used Seafoam before then it might've dislodged the family of rats living in your gas tank and sent them into the system. Here's what I would try:

1. Remove the fuel filter.
2. Disconnect the main line from the carburetor and put it down inside a jug or some sort of catch-can.
3. Get a can of the spray-type seafoam and spray it into the fuel line where you removed the filter, spraying toward the carburetor.
4. Take an air hose and blow it through the line in the same direction so the seafoam and any junk that blows out will go into the jug/catch can. Don't go overboard with the air pressure, a few PSI should suffice.
5. Replace fuel filter with a new one just to be safe. Hey, at least they're cheap!

That should eliminate a clogged line as the cause of your problem, at least between the pump and the carb. There still could be junk clogging the pickup tube in the tank, but I'm betting your pump is on the way out if you still have problems.

sa7

iTrader: (13)

Thanks guys, now I have a better idea of what to check and what to fix.