Ran codes need some interpretation:

[Christopher Johnson]

I bought a code scanner and already got my monies worth.

I got 3 codes: 2 codes for my o2 sensors and a code for "Fuel Pump circuit fault".

Can someone explain to me what the fuel pump circuit fault is and what repair I need to do?

I ordered O2 sensors and a throttle position sensor and it will be at the store in 2 hours. Now I just need to check this fuel pump fault.

 

[SteveVB]

87,95,96??

Whats the number? I can look up the diagnostic routine in my FSM if you have a number- and my FSM covers it.

 

[Christopher Johnson]

Here were my codes at Pep Boys:
136, 172, 181, 189, 411, 538

Several pertain to O2 sensors.

Going with instinct I removed my Granatelli MAF and replaced it with the stock one. It takes only 2 minutes.

The car has been running smooth all day since I did that. No codes showing up yet. I am still replacing the O2 sensors since those codes did come up on the stock MAF before. I also replaced the throttle position sensor today for good measure.

However, all the other major oddities I was having seem to have been resolved going with the stock MAF. In my opinion, the Granatelli MAF was the worst purchase I have done. I suppose when I dyno tune a computer chip next month the Granatelli may be incorporated again but in all honesty I doubt I really need it. It is possible the MAF may need to be recalibrated back at Granatelli Motor Sports.

Some other things their diagnostic came up with was Cylinder Imbalance, Possible wrong mass air flow sensor (I resolved that), Lean exhaust at cruise speeds, and vacuum leak to charcoal canister. A fuel pressure check showed the fuel pump to be fine.

Monday I am going to install the O2 sensors and resolve the vacuum leak. My goal will be to resolve any code that pops up between now and when I dyno tune the chip. I suspect the Cylinder Imbalance MAY be a fluke due to the other problems floating around: MAF, O2, Vacuum leak. We'll see.

All I can say is right now I'm running a lot better with the stock MAF and I hope the new O2's and the vacuum leak fix will put my rebuild where it was intended to be: Prime Time.

Question--where is this vacuum leak at physically?