seanof30306

iTrader: (4)

89 Formula LO3

Haven't started it in several months ... battery was dead.

Got new battery installed; started right up.

Ran perfectly for 30 seconds, or so, then died.

Restarted, ran for 10-15 seconds, then died again.

Spun and spun, not even a sputter.

Checked coil output .... good.

Injectors were spraying fuel when the starter was spinning the engine, but the fuel pressure gauge I have installed showed 0 FP with the key hot, but the engine not spinning, and only rising to about 2lbs FP when it is spinning.

Tried starting fluid; it fires immediately, but dies right away.

I'm thinking the car ran at first on fuel that was already in the fuel line, but it ran out. I'm guessing it's either a clogged fuel filter, or the fuel pump is not working.

How much FP should it have with the key hot, but the engine not spinning?

How about when the engine is spinning?

Any other ideas?

Thanks

Fast355

iTrader: (2)

You are going to have to drop the tank. Its probably not the pump seeing that you have 2 psi. What happened is the pressure came up, the car fired and then the fuel pump connnector hose in the tank burst. The rubber fuel hose between the pump and sending unit is known the split open and blow to pieces. I just had to pull the fuel tank and replace the split hose with some fuel injection rated hose and new clamps.

seanof30306

iTrader: (4)

Thanks, brother. I was afraid I was going to have to drop the tank. I'm 3 weeks post-op on having a titanium plate and 8 screws put in my right wrist to fix a broken bone. I'm "screwed", in more ways than one.

seanof30306

iTrader: (4)

I do have a question about the FP. It seems odd to me that there would be 0 FP with the key on, but not cranking, then go up to 2 PSI while the starter is spinning the motor. With no mechanical fuel pump, I don't understand why it would go up while cranking.

UnderCover89TBI

iTrader: (25)

when you first turn the key on the fuel pump relay engages fuel pump, then after cranking it turns to the oil pressure switch to supply power for the pump. oil pressure raises when cranking.

normal operating range for TBI is 9-13 psi.

IMO if your dropping the tank. Might as well install a new fuel pump while your there.
EP241 TPI pump is what you wanna upgrade too.

SCCAjunkie

+1

It's a bitch of a job, so grab an AC Delco EP241 pump off ebay for $50 and throw that in when you do it.

Even so, I'd try the filter first just to see, since you'll want a new filter anyway...

seanof30306

iTrader: (4)

I agree on trying the fuel filter first. I'm going to replace it, anyway, so it just makes sense to do it first and see what happens.

I searched the tech articles on dropping the tank and replacing the fuel pump, but didn't see anything. Has anyone done a write-up on it?

SCCAjunkie

Not sure there is a write-up, probably because it takes so damn much time and effort that no one wants to write it up when done...

Essentially:

Drain the fuel tank. Get the back end of the car as high as you can. WAY up.
If you've never had it apart, soak EVERY bolt with PB Blaster.
Disconnect the rear swaybar and shocks while supporting rear. Also undo the clamp that holds the brake line near the fuel lines. This *should* allow you to get the rear to drop enough. Remove the Panhard Bar and brace. Pull the rear wheels. Lower the rear as much as you can.
Remove the back half of the exhaust. Remove all the heat shields.
Remove the fuel filler door and surround.
Make sure the fuel pressure is out of the system, and disconnect the fuel hoses and wiring.
Loosen and disconnect the straps that hold the tank. Pivot them down out of the way.
Pull the tank completely out of the car.
Use a mallet and screwdriver to loosen the retaining ring on the top of the tank. Carefully pull the pump and hanger (some tanks are baffled, so you may have to gently twist or turn to get it out).
Replace the pump (the pump usually has specific instructions with it).
Installation is the reverse of removal. (I hate saying that)

If I missed something, please fill it in, as I did this from memory. I'm half decent at mechanical work, and my car has been apart MANY times so my stuff all loosened with no breakage, and it still took me 4 hours by myself on my back in the driveway doing this. One decent delay was trying to get the tank to drop without completely removing the exhaust, and not having the rear axle dropped low enough. I think that now that I've done it, I could do the job in 2-3 hours in the driveway, and definitely 2 or under on a lift. Good luck!

Fast355

iTrader: (2)

Reminds me why I have no problem driving a Van, despite what others say about them. The 33 gallon tank simply falls out after you remove the hooks from the frame after loosening the two large nuts holding the strap up. One fill tube and vent tube, one fuel hose, return hose, and evap connection as well as a fuel pump harness connector and its free. Total time to change a pump, laying on your back, about 45 minutes. Long live the G-van.

seanof30306

iTrader: (4)

Here's the latest challenge. The custom, mandrel-bent 3" intermediate pipe is welded to the Flowmaster 40 Series muffler, as are the tail pipes.

Gonna call the exhaust shop tomorrow and find out where to cut it for the best fix later. I'm guessing as close to the over-the-axle bend as possible.

SCCAjunkie

Mine is cut about 2/3 of the way back the straight run. I have a stainless band clamp holding it together and it works great.

seanof30306

iTrader: (4)

UPDATE -

OK, took the gas cap off, had someone turn the key, and listened at the tank. I could hear the FP, so I know it's running.

Changed the fuel filter, no good.

So, it's time to pull the pump.

Cut a hatch to get to it:



Now, how do i cut the fuel lines without blowing up the car?

morgsie

iTrader: (1)

why would you cut the fuel lines? just undo the fittings. those hard lines you see are part of the sending unit BTW. if you cut them you will need to purchase a new sending unit to repair them.

seanof30306

iTrader: (4)

I don't believe that is correct. In order to get the fuel pump out through a trap door on a 3rd gen, rather than by dropping the tank, you must cut the fuel lines.

morgsie

iTrader: (1)

I would try disconnecting the lines and attemp to remove it, I bet it can be done. I do not trust rubber hose and hose clamps on high pressure lines.

seanof30306

iTrader: (4)

You've done this?

thomas1976

Make sure the tank and the lines are empty. Also, need to be cut pretty short.

seanof30306

iTrader: (4)

Thomas, I don't understand what you mean by "need to be cut pretty short"

imeredith

When I needed to change my fuel pump, I debated on cutting an access hole and went so far as to pull back the carpet to measure it. When I did, I found someone before me had horribly butchered a flap into the sheetmetal already. I was a bit shocked at the job that had been done, but also relieved that I could access the fuel pump the easy way and still keep a clear conscience since I had not been the one to cut it. Somehow or other, the previous shadetree mechanic had done it without cutting the steel lines, but I did. I cut them all four in slightly different places (so the clamps wouldn't all be right side by side since the lines are very close together). I used some tin snips to make the initial cut, then used a pipe cutter to cut about 2" out of each section and clean up the cuts. I marked the lines on each side with a permanent marker 1-4, although in hindsight I might have used color coded zip ties as the marker got smudged a good bit while I worked. I sealed it back up with fuel injection rated rubber lines and double clamps and have had zero leakage issues since.

thomas1976

If the hard lines on the sending unit are too long you will have a hard time getting the strainer and pump out/in.

seanof30306

iTrader: (4)

OK, so you are saying to cut them close to the sending unit?

imeredith

I cut all 4 of mine on the straight section before the first bend.

Jeffs82TA

iTrader: (1)

loosen the sending unit lock ring that will allow you to raise the lines to cut them, then hack saw the lines 1/2 way between the bend in the lines and that piece a metal that secures those two lines. Then use efi band clamps & hose for the feed line and regular line for the rest.

GM should have done the access hole in the first place! Plus added quick disconnect fittings like the fourth gens have. Isn't a safety issue whatsoever nor a structural issue. Haha think airplanes don't use doublers all over and yet you get into them. You can lay on your back for many hours dropping a fuel tank because if you say you can drop the tank in a hour I call BS! I like the 30 minute lift the carpet open the cover change the pump and be back on the road idea.

thomas1976

Yes. Just leave anough to safely clamp the connecting hoses over the lines.


I agree. One of many things GM should have done in the first place.