RotorJoe

Some background information. My A/Fs used to be around 10.5-11.5 all the way across the map under boost. Only during idle and cruise do I see A/Fs around 12:1.

Now here is the problem. It idles fine. When I try to give the car gas I see my A/F ratios go up to16:1 and even 20:1 and this is just in neutral with no load. If I hold the gas at any RPM range (even at 7000) in neutral my A/Fs are around 14-15.
If I try to drive it, the car wants to stall and my A/Fs are very high (above 14:1 in most cases).Once the cars is rolling it will cruise just fine with A/Fs around 12:1 and 13:1 which is leaner then normal.


If I start to build boost pressure (just coming up on zero boost) it falls on its face, back fires a bit and I see my A/Fs go up to 20 in some cases. Knock stayed low and I never brought it passed 1-2 psi while trying this.


I have just bought new primaries (550s) and my secondary injectors are 1300s which are pretty old. I should’ve had them flow tested while the primaries were being replaced, but I didn’t. My FPR showed 50psi at idle (which is high but normal for me) so I pretty sure the pump and fuel filter are not the case.


Does this sound like a failed secondary to you guys?
Suggestions and thoughts are welcome?


Thanks

boostin13b

Check to see what the fuel pressure does when you rev it. And it's best to check everything out on the dyno so your not driving on the street. Could very well be your fuel pump, I've seen the same problems on a few cars with the RX7store.net fuel pump.

Another possibility, maybe you accidently changed something in your map with the secondaries to make them either leaner or richer. Too rich of a mixture could give you a lean readout on your Wideband. But you would probably know if that was the case because you would look like a Diesel cruising down the road when you would have this problem.

RotorJoe

The fuel pump was making more noise then normal, but it was hard to tell.

I will monitor the fuel pressure when I rev it, I was just out of time this morning. I had to get to work.

I thought it could be a problem with the settings so I quickly loaded the previous setting (datalogit) but that didn’t help any.

Thanks for the input, I’ll start looking at the fuel pump.

RotorJoe

It is the fuel pump. The weird thing is the fuel pump failed in stages.

It worked fine the night before.

Started it the next morning and it had enough fuel and pressure to idle but once you move the car it dies.

Then I come home after work to test the fuel pump and it doesn’t even turn on and has no pressure. I then shorted the TEN and the GND pins in the diagnosis box in the engine bay. Still no joy.

Oh well, new pump is already on its way.

Thanks for the help.

Rotarded

Catagorically incorrect!

The fuel pumps sold at the RX7Store are the same Denso, Walbro, Mazda, Apexi, and HKS pumps that you can get elsewhere.

http://www.rx7store.net/index.asp?Pa...S&Category=260

There is absolutely no reason on earth to qualify that they are "RX7Store" pumps, nor prone to failure due to the origin of purchase!

DaleClark

iTrader: (55)

The TEN and GND won't do anything - you have to short F/P and GND. That will run the fuel pump with the car off and the key in the "on" position.

The stock fuel pump is VERY hardy and RARELY fails. Double-check everything, but something in that system is your culprit.

Dale

TwinTurbo93

I guess you're lucky the pump didn't fail suddenly while boosting high psi...

RotorJoe

Sorry that was a mistake on my part, a bit early in the morning. I shorted both at seperate times. The F/P to GND first and still saw no pressure at the FPR gauge. I also didn't hear the pump any more.

Then I checked for codes just for an FYI. None popped up. But I am not sure my CEL works properly either. But thats a seperate situation.

I also tried to start the car a few times. No pressure and the pump was not making noise. I am sure it is the pump now.

I have a new walbro coming soon.

RotorJoe

Yeah no kidding. My new motor (1200 miles) wouldn't have liked that at all.