Last night on my drive home from school the Chevelle started to act really strange. I was driving approx. 60 mph on the freeway and the car started to act like it wasn't getting any fuel, almost as if I took my foot off the pedal (Note, the lights didn't flicker or dim, so I don't think this is an electrical problem). Then, when I removed my foot from the gas pedal and re-compressed it, it would run okay for about 3-5 seconds, then the same thing would start over again. Same thing would happen when I was under a load (going up a hill). When I push the pedal harder while this is happening I either get a very choppy acceleration or a mis that seems to be coming from the intake. The strange thing is, just cruising around town at speeds of less then 35 mph doesn't seem to have this problem. Please advise, Thanks.

'77 350 w/Rochester Quadrajet. Been using the fuel pump from the 307 for a few years.

I would check for a clogged fuel filter first. A little water from the bottom of the tank will stop it up real fast. Anyway sounds like its starveing for fuel.
Good luck, Bob J.

It could be a fuel pump going bad, or it could be as simple as dirty fuel filter or a cracked fuel hose somewhere in the system that's allowing air to enter the system. You'll need to check the pump pressure first. You want to see 4 to 7 psi from a stock pump. Then inspect all the rubber hoses in the system, starting with the one right at the fuel pump where the line from the frame connects to the pump inlet. Then, you need to move on to the hoses by the tank. To check those, you need to put the car on jackstands because you'll need to get under it. The hoses connect between the steel lines on the frame and the tank. If you look directly above the rear end directly above the the gear housing, you'll see these hoses. Make sure they're not dried out and cracked. The ones on my 71 were completely rotted away. If all this fails to resolve the problem, you may end up pulling the tank and changing the sock filter on the end of the pickup tube. Before you drop the tank though, make sure the rest of engine is in good shape as far as tune-up items go. If you still have points, replace them and the condensor. Check the timing and make sure it's advancing when you rev the engine. As for checking the fuel system for bad hoses, that's something that needs to be done anyway, so this is a good time to do it. Just be sure the basic stuff first before dropping the tank.
Always start troubleshooting by checking the easiest and most inexpensive things first, and work your way up to the more difficult and expensive.

I had that problem once on a 4 yr old Monte Carlo. It was the gas tank sock getting clogged with rust. After idling a few minutes, the rust would fall off the sock and everything would be fine for a while, then it would want to die again. Removed the sock, cleaned out the tank and no more problem. Just be sure to have an in-line fuel filter.

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von '69 300 Dlx SS TC #15 ACES #1575
My '69 SS (http://sites.netscape.net/von69ss/homepage)

Does this car have points? If so, are they AC DELCO. I had a friends car that was doing what your car is doing and it was the points, he had Blue Streak points in it. Also, check the fuel filter in the front of the carb.

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Leo Paugh
Maryland Chevelle Club #017
A.C.E.S.#3731
progress has little to do with speed, but lots to do with direction.
Maryland Chevelle Club (http://www.chevelles.net/mcc/mcc.htm)

i still have the same problem with my boat
it has an 305 brand new.changed
the carb,fuelpump (have ok pressure)
all in the ignition (it`s a chevy 305 mercrusier) over 3250 rpm it just won`t
run and i get mist in the carb and it starts to back fire if u get your problem sorted out please let me know what u did
wahlstrand@mbox301.swipnet.se

el camino-72 daily driver (even in the snow
great heat system in this car)
saab 99 -83
dodge dart-75
cris craft -86
ugly dog -00
(and yes we lost the icehockey)
thanks, mike

Thanks guys, for the responses and advice. Just to update, I changed all the fuel hoses coming off of the fuel pump and the fuel filter. I thought I would get adventurous and decided to open the quadrajet and change the float. When I saw all the rods and linkage inside the card, I decided the woods were a little to thick for a Sunday night and buttoned it back up. Put everything back on the car, adjusted the carb and it ran great this morning. Now I just need to check the fuel hoses back by the tank. I bet that's where the intermittent gas smell is coming from. Thanks again guys. By the way, It's an HEI, no points.

Dave

I can't believe I just spent an entire weekend on a fuel pump!

Just a quick update, the car ran okay for one day after I changed the fuel filter and then same old crap started again. So I did the next thing on the list which was change the fuel pump (Note, changed all rubber hoses and fuel filter, tightened all bolt on carb). I broke one of the fuel pump bolts off in the block http://www.chevelles.com/forum/mad.gif and spend all day Sunday trying to fix it, only to discover that the other fuel pump was fine. What a humiliating experience!

I guess the next step will be to drop the fuel tank. What should I be looking for here, any tips? Should I just buy a new tank? (never done this before, and I'm on a budget) Is the old one repairable? I did notice a little surface rust in one of the steel fuel lines, nothing serious though. (New fuel filter still looks good. Well guys, any advice here is greatly appreciated. I probably won't get to work on it again until Friday or Saturday.
Dave

So, did you forget your other UserName? http://www.chevelles.com/forum/smile.gif Had me confused there for a second.

Did you flush the lines? If there was/is rust or whatever in there, it could have moved up the line. Also, do you have a fuel pressure gauge? If your fuel pressure is constant, the problem is in your carb.

Sounds like the fuel sock (internal tank filter) is clogged or their is trash/rust clogging it. You'll need to drop the tank and remove the sending unit to get to it.

Hope that helps

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69 Chevelle, 350, TH400, 12 Bolt, in process

Yeah guys, I lost the password and since I have a new ISP, I cannot retrieve the old one, so I will have this user name from now on. Thanks.

Dave

Hey, you can't change names in the middle of a post like that. http://www.chevelles.com/forum/biggrin.gif

I'm with mr2fast. We had changed carbs on my kids 67 because it was running really bad. We did all the usual tune up stuff first though. Still ran bad. After the new carb made it run better, he wanted a new intake. We put the carb that we new ran good back on, but it wasn't getting fuel. Changed the fuel pump,no go. Finally I blew in the end of the hose, and now it gets fuel. We too will be dropping the tank. Cal

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TC Member # 1308
http://72sselcamino1.tripod.com/calscaminos/

[This message has been edited by 72sselcamino (edited 03-12-2002).]

If the prob returns, test both the primary and secondary sides of the coil...

Okay guys, I'm back again. Update: I dropped fuel tank and removed sock. The sock looked good, except it was brittle so I got rid of it. Fuel line is clear, and man, gas doesn't taste too good. So far I've:

-replaced fuel filter
-replaced fuel pump
-replaced rubber fuel lines
-removed sock in fuel tank
-blew fuel lines out
-tightened down bolts on carb

What's the next step guys? Do you think the float could be set too low? How does a cam behave when its screwing up? I'm all ears.

Dave