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94 Saturn SW-2 Stalls at lights or after taking foot off gas

My 94 SW-2 wagon (160k miles) seems to be stalling when just winding down to idle, like at traffic lights. I’ve had this problem for a long time being that I’ve had the same mechanic pull codes on it and find that it had a problem with the EGR valve which he replaced. After that, it worked a while and then after about a few weeks, it started to stall again. He checked the codes on it again and this time it came up as Mass Air Flow valve which he replaced. This time it hinted at a cough at traffic lights, then, after awhile, it started to stall again. I’ve already put too much money into this and just want to give up. Anyone have any idea what could be causing this? Or is there anything I can try myself that won’t break the bank?

Thanks.

try replacing your fuel filter sounds like its just way to dirty or clogged not allowing the gas to flow through.

I don’t think the fuel filter will be the problem since it happens when the fuel demand is low- a fuel filter is more likely to show a restriction during demand for a lot of fuel (hard acceleration).

If your mechanic has an OBDI scan tool, he should be able to check through all of the sensors and see what they are reading. Usually if the input from all sensors is right, the fuel output will be right. I’d start by looking at the TPS.

Another possibility is that the throttle blade setscrew needs to be adjusted- in the old days this would have been called your idle speed adjustment screw, but that’s not really correct any more. Anyhow, your throttle blade is only supposed to close “so far”, and there should be a setscrew to adjust how far the throttle blade is staying open. At idle the IAC motor will usually control idle speed, but if your throttle blade is too far misadjusted then the IAC can’t react quickly enough and it’ll try to stall.