Expert: Sean Halliday - 9/5/2007

Question
Hi.. I have 93 Nissan sentra ECCS manual trans..i just bought the car and my 1st problem was that it died out in the middle of an intersection 3x but it started right away.The gas gauge read 1/4 tank but 2 make sure i put gas in it agian and ran fine.In the morning, cold start the rpm would go up and down until i rev it up then still the needle fluctuates from 1000rpm to 800 rpm and wen i'm goin in reverse it dies out..one day i traveled far wen all of a sudden the car started surging and tried to pump the gas pedal but the engine wud not start. after it died out it would start with no problem. we replace the fuel filter,plugs and even the fuel pump just to find out that fuel gauge was 1/4 reading improperly.wen added gas it would have no problem except that the rpm would still fluctuate     with the a/c running.adjustments were made with the iac but no improvement..what would be your recommendation to solve the problem..tnx

Answer
Surging is usually the fuel regulator or EGR valve.Check also the mass air flow and TPS sensor....throttle position sensor.If you remove the mass air flow sensor and the idle changes but the engine doesnt die then thats your problem.Test with the A/C off.