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Fd sputtering, hesitating on 1/4 throttle

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Fd sputtering, hesitating on 1/4 throttle

#1 Post by Mezz » Thu Nov 23, 2017 4:25 pm

Hi everyone im new to this forum and to the rotary world. Im having issues with my stock fd. It would be great if you could help.

So when i bought my car a month ago the boost gauge was not working: sitting at the bottom -20 and it was/still running rich and fluctuating at idle but drives fine on acceleration.

I drove it yesterday and it was running as mentioned above until today. As soon as i drove out my driveway it sputters and hesitates at 1/4 throttle. The boost gauge also started working but was still sitting at the bottom and did not move passed 0. The car does NOT stall or shut off.

I have replaced the vacuum hoses to silicone hoses last week.
Could this be a TPS or MAP sensor issue?

I tried uploading a vid but would not work

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Re: Fd sputtering, hesitating on 1/4 throttle

#2 Post by DKWW2000 » Fri Nov 24, 2017 2:08 am

I have just had a very similar problem with my FC TII, kept dropping in/out of boost, checked all the obvious until a rotary Guru friend :bow: told me to check the Electric OMP connections/clean them........low & behold problem solved.

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Re: Fd sputtering, hesitating on 1/4 throttle

#3 Post by KYPREO » Fri Nov 24, 2017 9:55 am

What version FD?

The solenoid box is known to go. I recall Mazda upgraded in the solenoid box in series 8 models (Version V & VI) but even though they still require replacement periodically. Solenoid and vacuum line issues can be very tricky to diagnose and produce all sorts of weird behaviour.

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Re: Fd sputtering, hesitating on 1/4 throttle

#4 Post by Mezz » Fri Nov 24, 2017 11:03 am

Its a '99 Type Rs version 5

The vac hoses were very brittle around the solenoid box.
Is there anyway to test it?

I've also had a quick look around the omp, seems to be some oil around the hoses. Ill check it out properly when i get home from work

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Re: Fd sputtering, hesitating on 1/4 throttle

#5 Post by Slides » Fri Nov 24, 2017 9:58 pm

There is a fault finding post in tech section at seems to be mostly Australian guys there, not sure why they needed a separate forum but there is a lot of fd specific tech there.

Could be an electrical issue in several places. If it was sriving ok and running on boost But a bit rough you may have a partial tear in the line to the MAP sensor on the firewall. Trace it back to the throttle.

Check over loom plugs and earths too.

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