So I've been having this issue with my car lately. When I do over 40-50, the car will accelerate to the speed but after driving at the constant speed (not accelerating or slowing down) the car will eventually sputter and die. I'll have to pump the gas (fill the pumps on the carb) and clutch kick it to get it to start back up while rolling.

My fuel system is a little different since im carb'd. I have the stock pump still in its location, but no power running to it. I have a Holley blue sitting on top of my gas tank instead (this is how I got the car, I didn't make this setup).

I opened my gas tank today and the bottom of it looked like complete S***. I took one of those magnets that is on a long stick so I could put it at the bottom of the tank. I did this 10-15 times before the magnet started coming back empty.

Is it normal for these cars to build up deposits of whatever this crap is? It doesn't look like rust, its not orange. It's black and it looks more like metal shavings than rust. I'll try to get a pic when I get home.

 

No its not normal.

I have had 5 Rx7s and none has had the problem you speak of.

Thats why your car is so sloooooow?

 

That is not normal, but it's common.
I'm on my 3rd tank, and I live in AZ!!

On this last tank, I used POR-15 gas tank sealer. No problems.
Those shavings and rust can really wreak havoc on your car. I lost a Walbro because of a rusty tank.

It will clog your lines, and filters; slowing your car and causing unusual fuel pres, varying AFR, leaks...

 

It's been an ongoing problem that I've had with the car lately. I have a Mallory FPR that at idle would show 7psi (standard for carb). I moved the gauge for it inside the car and drove around watching it. It was dropping to almost 3 psi and bucking at WOT in 2nd! Tried changing to a Holley FPR and it did the same thing.

I spent a good 1/2 hour digging the crap out of the tank. I haven't gotten to drive on it yet, had to go straight back to work (was on my lunch break).

 

I don't think emptying the tank will solve the problem. At the very least, you'll have to change the fuel filter, and the pick-up filter (I don't know if carb'd applications have this, but EFI does).

You can be sure tho, that the shavings are causing your symptoms. I would change all filters, coat the tank and run a little stabilizer through the tank to clean the lines.

The POR sealer is $80 for everything you need to seal the tank.

https://www.rx7club.com/showpost.php...&postcount=402

https://www.rx7club.com/showpost.php...&postcount=406

 

Yeah, I still have the stock pump just no power running to it. My pump is a in line just outside the tank. I cleaned off the sock for it when I had the tank open. I couldn't tell if the pump even had a sock when I first pulled it out. It was this big black nasty mass. I'll run something through the lines to make sure its all cleaned out as well.

All the gremlins you find when you buy a car that's been sitting for 5+ years...

 

I hear ya man, Take a look at the link in my sig... it's been 3 years and still going.

good luck.

 

Yeah, I've looked at yours before. I have a LOT of free time on the computer here at work.

I really like the way your AI system is set up. Very stealthy.


This fuel problem has been bothering the **** outa me for about the past month now. I finally decided to do something about it when I was playing with a Civic yesterday that was pulling on me at 100.