I have owned various FCs since 1995 and my current daily driver (1991 GXL) has an issue that I can't figure out.

On hard left hand turns I get what I am 99% sure is a fuel starving problem. The first time I noticed this was about 2 years ago at an autocross. I just assumed it was because the fuel was sloshing away from the pickup and the pump was sucking air. At the next event I had a completely full tank of gas and the same thing happened, again only on hard left hand turns.

About a year ago it started doing it on not so hard left hand turns so I would occasionally get it turning fast at an intersection.

I put a new fuel pump on it around 3 years ago. Twice now I have pulled the fuel pump out of the tank to make sure the pickup was attached correctly and the wires were not shorted out.

Any suggestions on other things to try and look for?

 

Off the top of my head I'd say rusted out fuel tank baffles.

I'd put a fuel pressure gauge teed to the fuel supply and shake the car while stationary or wiggle some wiring around the fuel pump. You can also jumper the fuel pump test connector (yellow plug near the boost sensor) and go for a drive.

 

so your saying this is in more then one rx7 you have driven. so likelyhood of it being rusted out baffles is highly un likely.
i've seen rx7s with a pick up also on the bottom of the tank. "sump pump" or "sump tank " i forget what its called but its something like that.
where it pumps fuel from the bottom of your tank so you dont lean out and pop

 

I have had this EXACT same problem under exactly the same set of circumstances.
This may sound like a silly question but when you replaced the pump did you clean off the sock filter?
My issues went away over time, just as a friend had told me they would, because HE went through the exact same thing.

 

Weak alternator or a shot BAC valve would do it.

When turning on neutral with the AC on and power steering to the max with some accessories, the engine can die due to low voltage.


PM and Ask my cousin how he knows Ncharlebois

 

Replace the sock filter at the bottom of the fuel pump. Just do it.

 

This man Gets the Prize..lol!..+1 for this,and also the fuel filter should be replaced too.

 

At first I thought the "clean/replace the sock filter" advice was crap. Especially as I used some brake cleaner, as recommended, and saw no dirt or gum or crap come out of it. But after I put the pump back in (BTW: the inside of the tank was perfect, baffle around the pickup was perfect) I haven't had a problem with it since. Even on especially low tanks of gas (sub 1/4). Color me surprised.

 

pfsantos: Fuel tank is perfect on the inside. No rust or varnish.

fc3schick87: This has only happened on my current daily driver.

scrip7: misterstyx69: HotRodMex: I did reuse the old sock filter in the tank but it "looked" perfect. Looks like I will hit the dealership on Monday.

I will post the results once I get a chance to replace the filter.

 

If you were to look at your old sock filter under a strong magnifying glass you would see why it won't pass enough fuel, even after "cleaning" it with brake cleaner.

 

Holy thread resurrection batman!!!

Here's the quick nitty gritty of my problem

Left hand fuel cut issues (full tank, half tank, empty tank)
New fuel pump (less then 2 yr old) from rx7.com
Haltech e6k
Brand new fuel filters (both of them, less than 50 miles)
On long drives my fuel will start to surge (afr's go crazy, when parked and checking my fuel pressure gauge after a long drive it will bounce from 20-40 psi. Fuel is set to 44psi per my aeromotive fpr (less than a year old))
Someone please help. My tank is not rusted, it's been recently boiled out and re coated by a professional shop. I'm at my Witts end :/

 

yoshi, monitor the pump voltage while the pressure is acting up. backprobe with a voltmeter and drive. if you can monitor amperage, that would be even better. this will tell you at least if it is mechanical or electrical in nature. then you can further diagnose from there.

 

So run a power wire from my pump to the volt meter (since my meter isn't long enough) and monitor it while driving right?

I was going to make a custom fuel pump harness next with a relay and inline fuse and see if that helps but seeing it act up via a volt meter first would put me more at ease.

 

use whatever works to monitor. you can also just extend your leads using alligator clips. and yes, before spending any time on it, let's try and narrow down the problem

 

I can see pump voltage being an issue but wonder if it would only happen on left turns...that seems odd.
I would consider taking a look at your tank venting, see if something is going on there.

 

It does not only cut out in left turns. How I meant it was when it starts running rough (acting up and leaning out under throttle) it will completely cut out in a left turn.

 

doesn't really matter what induces the symptom. couldeasily be a wire that shorts when slightly tweaked by a turn. what matters is that you start from the top and cancel out one of two broad categories. this removes a plethora of possibilities with one swoop, and sends you on the right track to further break it down