Fuel cut on left hand bends/corners

matty hall · Postby **matty hall** » Wed Oct 17, 2012 9:58 pm

Please direct me to a thread if this has already been covered.

Basically when I either turn a sharp left corner fast or drive quickly around a long sweeping left the fuel will surge/cut out.

I initially thought it was a dodgey and old fuel pump so I replaced it, but the problem is still there.

Any ideas what it may be and if this is a common problem

Cheers, Mat

Postby **Okibi** » Wed Oct 17, 2012 10:22 pm

MX-5s do plenty of autokhanas etc. without anyone having this issue.

How low are you running your fuel tank?

Have a look at other items that could be effected my momentum, is your battery secure and doesn't wobble on the brackets? AFM sensor plug loose? coil pack bracket loose? movement in the intake plenum? Is the 02 sensor plug in tight?

matty hall · Postby **matty hall** » Wed Oct 17, 2012 10:42 pm

Okibi wrote:MX-5s do plenty of autokhanas etc. without anyone having this issue.

How low are you running your fuel tank?

Have a look at other items that could be effected my momentum, is your battery secure and doesn't wobble on the brackets? AFM sensor plug loose? coil pack bracket loose? movement in the intake plenum? Is the 02 sensor plug in tight?

It starts to cut when its just above a full tank.

AFM has been deleted
Battery is secure
I have a wideband and is working perfectly

Will have to check coil packs and intake plenum tommorow but I am convinced it is a fuel cut.

Thanks for the feed back.

Postby **Okibi** » Wed Oct 17, 2012 10:56 pm

I seem to remember SPs had an issue feathering the throttle just on boost (as you would trying to balance power/traction) mid corner, I think that was a tuning issue, perhaps you are experiencing the same.

Any more detail about the car / ecu etc?

matty hall · Postby **matty hall** » Wed Oct 17, 2012 11:14 pm

Car is a 1993 na8

only simple mods to the motor so far including:

Adaptronic PNP ECU
enlarged intake piping/deleted AFM
mania firewall air filter
RSR 2.25 inch exhaust
X force headers
walbro fuel pump (today)
Brand new spark plugs (today)
timing has been advanced, but to what degree i cant remember

Car was bought stock a few weeks ago and never dríven stock except home from previous owners house. put all parts that are listed above in from my old car and took it to mania for a tune. on the way to mania i noticed the "fueling" issue and presumed it was the pump so therefor bought a new pump. All got tuned today and seemed fine untill i got it home and went for a bit of a spirited drive and noticed the problem was still there.

Postby **NitroDann** » Wed Oct 17, 2012 11:24 pm

Im going to call a shortcircuit that happens due to cornering forces, it isnt surge if the tank is full.

Dann

Hjt · Postby **Hjt** » Thu Oct 18, 2012 12:24 am

Agree with Dann, my escort panelvan used to cut on hard right hand turns. Dodgey

93_Clubman · Postby **93_Clubman** » Thu Oct 18, 2012 12:40 pm

Russellb explains the fuel starvation issue on left turns here:
viewtopic.php?f=29&t=45597&p=575578#p575578

Or it might be the 'black wire' issue:
viewtopic.php?f=55&t=46425

wozzah1975 · Postby **wozzah1975** » Thu Oct 18, 2012 5:24 pm

matty hall wrote:Please direct me to a thread if this has already been covered.

Basically when I either turn a sharp left corner fast or drive quickly around a long sweeping left the fuel will surge/cut out.

I initially thought it was a dodgey and old fuel pump so I replaced it, but the problem is still there.

Any ideas what it may be and if this is a common problem

Cheers, Mat

Your first step would be to actually confirm you have a fuel pressure problem, and attach a fuel pressure gauge and monitor it whilst making the car surge.

Have you done this?

Cheers
Woz

Postby **Okibi** » Thu Oct 18, 2012 6:51 pm

93_Clubman wrote:Russellb explains the fuel starvation issue on left turns here:
viewtopic.php?f=29&t=45597&p=575578#p575578

Great link, I hadn't read that post before.

matty hall · Postby **matty hall** » Fri Oct 19, 2012 5:01 pm

Sorry guys, I thought i had replyd to this on my mobile but it hasn't seemed to work.

After reading both those articles i am leaning towards the issue being within the fuel pump and not a wiring issue.

I will have a look at the pump again this weekend and maybe swap it with a genuine one out of my other NA and see if it fixes the problem. If not i will have to use a pressure regulator or have a look at the "black" wire.

Thanks again for all the help and hopefully will have it solved this weekend.

cheers, Mat