kan ikke tage gassen

[pkno]

Hej, Jeg har lige købt en Corvette fra 1984 med crossfire injektion, den vil ikke tage gassen hvis man trykker gaspedalen helt i bund, så dør den ind til man slipper igen og giver stille gas igen. Selv om man giver stille og rolig gas, tager den alligevel ikke rigtig gassen ?? er der nogen som ved hvad der er galt ?? den starter perfekt og motoren lyder godt når man holder stille, og når den holder i tomgang lyder det ikke som om der er nogen problemer med at tage gassen !

[david]

Ifølge denne gennemgang er det højst sandsynligt benzinfilteret som er synderen:

 

 

My car starts and runs, fuel is correct at cruise, but has no power or runs lean at WOT or rich at WOT...

#1 Check fuel pressure and volume. 90% of high performance concerns are fuel pump or filter related. A dirty 'in tank' filter sock will restrict even the best fuel pump. #2 Restricted injectors. (Lean) This problem may or may not show up at highway cruise, but is very noticeable at wide open throttle. Remember the brake specific fuel consumption rules when picking injectors for your application. Cheap injectors are not worth the money. Buy quality injectors, or have them flow tested. #3 Check throttle plate linkage for binding or incorrect throttle opening. Check TPS voltage (should be above 4.2 volts at WOT). Check for a faulty ESC (electronic spark control) system (no spark advance will result). #4 Check for 'false knock'. Any noise generated (whether real or RFI) to the knock sensor or KS circuit will automatically retard ignition timing. We once had a 454 SS truck that could hardly pull itself when towing anything--problem was a loose hitch ball, which sent the same knock frequency down the frame rails--and was picked up by the knock sensor. #5 Check for an improper spark plug gap or spark plug reach. Wrong plug reach can change the air fuel ratio, slow the flame front in the combustion chamber and cause increased emissions and very low power--and low fuel economy. #6 Dirty MAF sensor. If any dirt is on the sensing elements of a MAF sensor, the fuel rate is incorrectly calculated. This can harm overall driveability--and definitely hurt performance, as well as cause transmission problems and detonation. #7 Wrong MAF sensor or failed MAF sensor. The sensor can correctly show idle flow voltages, but cannot correctly show higher operating loads to the computer. Very poor driveability will results, and very high losses in power--and can result in eventual engine damage. Mounting the MAF sensor in a non-OE position (nearer to throttle body) can be affected by reversion pulses from the intake manifold--and result in incorrect metered air values to the computer. #8 Wrong in tank pump and regulator. For 2005, some suppliers are sending a complete pump and regulator for supercharged applications which are incorrect. If the pump and regulator from a VIN 'Z' truck is used, the resulting fuel pressure is 48-54 (335-375Kpa) PSI. Factory fuel pressure for 2005 trucks (other than a VIN Z truck) is 55-62 PSI.  Because of this unknown factor, we suggest getting the number right from the fuel pump before installing, along with the fuel pressure regulator number--BEFORE installing it in the tank. #9 New problem with some centrifugal superchargers is a unique phenomenon where at part throttle, the buildup in pressure barks back through the impeller--and is picked up by the MAF sensor. This causes an instant frequency change in the MAF sensor signal to the PCM--and results in a very rich frequency problem each time this occurs. Wide open throttle is fine, part throttle is very poor and jerky because of this. The only cure we've seen so far is a larger pulley to drop the supercharger boost pressure, or relocating the MAF sensor to the pressure side of the supercharger, just ahead of the throttle body.

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