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About oldscsc

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  1. My bet is on the fuel pump. Trucks of this vintage are infamous for the pump whine.
  2. June 13...Monday? I'm interested, but don't think I could make a mid-week meet.
  3. GMC is not GMC as far as dealers go. Each dealership is an independently owned and operated franchise. The dealer with the desirable pickup would not get credit for a sale if they dealer trade, and may potentially get a less desirable, harder to sell vehicle in exchange. If you go directly to the dealer with the pickup you want, assuming it is still available, I guarantee you could take it home. As for the cash sale argument, that will actually hurt you in the car buying game. Dealers make surprisingly little per new vehicle transaction; a much larger chunk of the front end's profit comes from the F&I (finance and insurance) department. They'll make far less off you without financing. If direct purchase isn't an option, try working the trade through a different dealership. Dealer to dealer relations often make or break a deal. Some dealers outright refuse to do business with other (often rival) dealers. Of course, dealers are not likely to tell you this outright as doing so would risk losing a potential customer. Stick with it and try not to get too frustrated. You can get the pickup you want, but you may have to be persistent.
  4. I believe the signal and tail functions of the tail lamp are taken care of by one dual filament bulb. Have you tried either swapping in a new bulb or swapping bulbs from side to side? Also take a look at the bulb socket contacts. They should be tight and provide tension on the bulb contacts. You can adjust these or get new sockets if necessary.
  5. Used to run AmsOil before switching to M1. In for trying it out again.
  6. HVAC: Probably a blend door actuator. Their failure is common on these pickups; unfortunately, that doesn't make the repair any easier. Long crank: Check fuel pressure with the key on and engine off. Spec is 55-62 PSI on 4.8/5.3/6.0 pickups. May be different for the 8.1. More specifically, leave the key on and see how long it takes for pressure to bleed down. I'm willing to bet your fuel pressure is bleeding down after the pickup sits for a while.
  7. Check fuel pressure at the Schraeder valve. Should be 55-62 PSI with the key on and engine off.
  8. I used to run Signature Series 5W-30 in my 2001 4.8, and it never turned red. Just got more black the longer it was in the truck. Just for reference..
  9. Take it to the dealer if it's under warranty. There is freeze frame data the dealer can access and use to aid diagnosis. Also, a flashing check engine light means that the PCM has detected a misfire severe enough to potentially damage the catalysts. If the misfire continues, it could lead to an expensive catalyst repair down the road. The more documentation you have that the root cause began under warranty, the better off you will be.
  10. Check your starter connections. If they are clean and tight, are you getting voltage to the starter when you attempt to crank the pickup?
  11. Bump. $3800 OBO. Just passed CA smog test on 1/23/16.
  12. Check fuel pressure as well. Spec is 55-62 PSI with the key on, engine off. The truck should hold this pressure after the initial prime.
  13. Two main things here. First is your speedometer. When you install taller tires, your speedometer will read slower than you are actually traveling. Your odometer will subsequently be incorrect, and hand calculating MPG will be off (lower) than the actual number your pickup is getting. Second is the wheels and tires. When you installed the 20s, you did two things: greatly increased the unsprung weight at each corner of the pickup, and effectively raised (lower numerically) your differential ratio. That means less torque multiplication. I'm willing to bet neither of these things are helping your fuel consumption. My suggestions: 1. Skip the gimmicky fuel economy improvers. 2. Swap the 20s out for stock (or similar) 16s. The smaller and lighter the tire, the better MPG you'll get. 3. If you keep the 20s, get the speedometer reprogrammed so you can judge actual MPG.
  14. Symptoms of contaminated fuel could be any of the following: -MIL "on" with misfire and/or fuel trim DTCs -Random misfire (rough running) -Low power (knock sensors pulling timing due to pre-detonation) -Poor fuel economy (due to retarded timing) -Hard start -Crank / no start Long story short, if you've been driving the truck for 2 weeks, I wouldn't worry about sugar in your fuel tank. You probably would've had some symptoms by now if they sabotaged your fuel tank.
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