12 replies to this topic

[Vance J]

I have an engine problem that's really got me stumped. My engine dies when making a right hand turn. It feels like your turning off the ignition. If I feather the throttle 1/4 or less it runs fine, but more throttle and it cut off. As soon as I straighten the wheel it runs normal. Also runs great when turning to the left.

This is on a 1994 Miata 1.8 engine.

I have checked the following:
Fuel pressure good.
No loose wires on engine.
No loose wires under the dash.
No wires touching the accelerator peddle or cable.

I have replaced:
Fuel pump.
Kill switch.
Engine computer.

Any ideas would be appreciated.

Thanks Vance

[MPR22]

Maybe AFM. I blame every bobble on my 1.6 on my AFM.

[Zauskycop]

Just the engine, or all power?

[Den]

grounds?

[Keith Novak]

Others have reported similar symptoms when part of the fuel tank baffle comes loose and blocks the fuel pump outlet when turning and the fuel is sloshing to one side.

[Vance J]

Some good ideas.

I have replaced the AFM with a known good one.

Yes, it is just the engine.

I have checked the grounds all are solid and clean connections.

My data logging computer monitors battery voltage which is solid. I also monitor the fuel pressure between the regulator and fuel rail and it is steady.

I checked the tank baffle when I replaced the fuel pump and it was not moving.

Thanks for your suggestions

Vance

[Randy Thieme]

This question might be a stretch but when more than 1/4 throttle causes it die do you think it might be throttle position or could it be lateral G? What I mean is more gas more lateral G. One time I had a damaged harness connector to the ECU. Seemed to be firmly attached but in right hand corners it would die. This was a 1.6L car.

[Randy Thieme]

P.S. Since you have a data logger is the RPM signal normal? Does it suddenly disappear or show any abnormal behavior?

[Vance J]

The rpm signal is normal along with all the other data points.

I also be-leave it is G force related. When driving around in the paddock right turns do not effect it. Only when on the track.

I've order a throttle position sensor to see if that helps.

Vance

[FTodaro]

When I recently replaced my motor, when installing it, i forgot to tighten the ground wire that grounds on the Throttle body at the top of the intake. When i would go out on the track the motor would run fine till i got to about 6300 rpm and then the tack on the data logger would start flashing and the motor would cut off. I replaced crank, cam sensors and finally found the lose ground. Fixed it. I would double check the grounds or broke wire on the harness coming off the injectors to coil before i started replacing any parts.

[Keith Andrews]

Vance, do you have an adjustable fuel pressure regulator? I experienced this earlier in the year and it was just a plumbing issue. The return fuel wasn't getting to the pump in left hand turns.

[SaulSpeedwell]

Bad ground to injector harness. Run an extra ground.

[Vance J]

I took the throttle position sensor apart (destroyed it) and found a bad spot starting ar 1/4 throttle. Hope this is the problem. Bothers me it only shows up in right hand turns.

I also going to replace the fuel filter and going to clean all the ground connections and put star washer under them. After that I will go test at a local track.

Thanks to everyone for your help and suggestions.

Vance