New SC with wierd codes

LoneStarSC

Registered User
I just got a 1990 SC, and after 2 days of perfect running I have some problems. I was almost home after 3hrs of driving and the check engine light came on and I felt some very mild hiccups under the hood. I stopped and the car would stumble around 500rpms at idle. It eventually died. I started it again and ran a code test (KOER); I got the following:

41 HEGO (HO2S) Sensor Voltage Low/System Lean
91 HEGO (HO2S) Sensor Voltage Low/System Lean
72 MAP, MAF, or BP Sensor out of range during Dynamic Response Test
73 Throttle Position Sensor Fault / Insufficient Range
25 Knock not sensed during Dynamic Response Test
74 Brake On/Off Sensor switch fault; not actuated

I don't think that all of these parts just went bad at once, so what do ya'll think is the best place to start?
 
Well........

During the KOER test, you need to at certain points snap the throttle and other times turn the steering wheel 180* and then depress the brake pedal and such. The lean codes are telling me that you have a fuel problem. Probably due to a clogged fuel filter. The mass air meter could be bad also, I have seen them go.

You really need to read the book for the code scanner and FOLLOW IT EXACTLY!!!! Otherwise, you will get eronous codes.

Hope this helps....

Don
 
My scanner book is not very descriptive during the test. It doesn't say anything about when to snap the throttle or turn the wheel. I am going to try the MAF and see what that does.

Since the car runs well at throttle and poorly at idle, do you think that it could be a fuel filter/pump? I have a pressure tester, what should the PSI be?
 
I just found a massive air leak between the supercharger and the top IC pipe. I think that this could be causing all of my problems. I'll order some gaskets in the morning.
 
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