My 93 Ford Explorer sometimes doesn't want to respond when I get into the throttle. the thing is, when the RPM go to 1300 then slowly drop to normal when started the car will run fine. But if it doesn't it will act lethargic. I've replaced the TPS, and MAF.
You are correct to suspect the MAF with this sort of symptom. The MAF detects the the amount of air entering the motor. If there is a vacuum leak, or more common, if the air boot that connects the MAF to the throttle body has a crack in it creating an air leak, then the new MAF will give the same bad readings as the old one. So first thing to do before replacing a MAF is to make sure there aren’t any vacuum leaks. The TPS is unlikely to be the cause of your symptoms.
It is common for there to be a crack in the intake boot that only creates a vacuum leak when it gets torqued by the motor or other variables cause the crack to open. In other words, it can be an intermittent problem. The best thing to do is grab the intake boot and move it around to see if the motor reacts.
Beyond this, you will need a scanner that is capable of viewing the vehicle data. This data is valuable for a successful diagnosis of your Explorer.
If you should need further help with this, I recommend the following inspection; car is not getting enough power inspection
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