Vroom...urk! Fuel delivery?

[capt_furious]

Hey folks,

 

(let me preface this - it's a 260 Z with a swapped in L28 running '72 round tops, and a Carter electric fuel pump at the tank, filters just before the pump and the fuel rail on the engine)

 

Was driving home from Sacramento yesterday, cruising along at 70 mph when out of the blue the Z lost power, started sputtering and eventually caught again. It then repeated the process and forced me to pull over. I got out, checked everything I could, brought the revs up, everything seemed fine. It'll free rev just fine while standing still.

 

I called AAA, got towed home(AAA Plus pays for itself without fail, every year. I paid nothing except a driver tip last night. It would have cost me $400 otherwise!). I let the car sit for a while, got changed, hopped in and drove off to dinner, and stuck to the back roads. No issues on the way there, tried to keep fuel demand low with the revs down and the gears high.

 

On the way back I had a little coughing at first, but the rest of the trip was uneventful and I even jammed on the gears a bit.

 

Fired her up for work this morning, had some trouble getting out of the driveway. 4 false starts, then she didn't give me any more problems except a sputter or two while cold.

 

So, filters? I'll change them anyway. Fuel pump? It's less than a year old. Carbs throwing a fit? No idea.

 

Thoughts?

[TrumpetRhapsody]

Go grab yourself a little autozone 15 psi fuel pressure gauge and install it inline on the feed line.

 

I found out my pump was putting out a measly 1-2psi at best, and was having the same problem it sounds like you have. Fuel pressure gauges are nice to have installed.

[capt_furious]

I picked up two new fuel filters to replace the current ones, and I got a little inline FP gauge as you suggested. I tore out the easy to get to filter and replaced it, then took the car for a ride - no issues. I decided I wanted to see what the filter looked like inside, so I stomped it open(plastic housing). Not much there, a little bit of sediment in the bottom. I'm going to assume the other filter caught most of it, so that one gets replaced when I've got the time.

 

Haven't put in the pressure gauge yet, I don't like the looks of the housing. It's just plastic, and that bugs me. I'd much prefer metal. I might be able to put some brass fittings together, t-fitting in the middle and nipples on the ends.

[Glliw]

I'm using one of those 0-15 psi autozone gauges on my 260z and the plastic hasn't burst or shown any signs of leakage. Just make sure to teflon tape it before screwing together.

[TrumpetRhapsody]

+1 It doesn't look pretty, but it works just fine. Just tuck it away out of sight.

[capt_furious]

I think it's fixed! I had a hell of a time getting to work this morning. Stall city.

 

I installed the inline gauge at lunch and fired the car up, and figured, 'crap, so much for that....the gauge is faulty.' It wasn't even registering pressure.

 

Then I hiked the car up on a curb, clambered under and swapped out the filter upstream from the pump. I fired the car back up, kept an eye on the gauge - hopefully - and the filter in the engine bay. I noticed the engine bay filter barely had fuel in it, then a surge of fuel came through, and a glace at the gauge told me exactly what I wanted - pressure!

 

A jaunt down to the bank and to get food, the car seems to run just fine again. I'm tempted to Dremel open the old filter and see what's in it.

 

I'll keep a jaundiced eye on her for the next few days, but I suspect my problems are over.

[capt_furious]

Just Dremeled open the filter that was upstream from the pump.

 

Lots of gunk in there. Filter element doesn't exactly look loaded up or clogged, but it definitely stopped a bunch of junk that would have made a mess of the pump. Glad I had a look.