Truck barely starts, super low revs, idles rough.

[JaneTheRockJohnson]

Hey all. New to the forum here.

I've got a 1994 Ranger XLT. 4.0L V6 OHV that I purchased a few months back. It's got 236,000 miles on it, but runs pretty well. The previous owner kept up with the maintenance regularly, and did a fair bit of work on it.

The last week or two, I've had trouble starting it. The engine cranks just fine, and eventually turns over, but the revs stay down around 250/300, and I can feel the engine struggling to stay running. At that point, I usually turn it off, and try again. Sometimes after the 2nd or 3rd try, it idles rough for a bit, but smoothes out.

I'm thinking it might be the MAF sensor, and am going to clean it, but wanted to see if anyone on here had any other ideas. Thanks in advance for your help!!!

 

[chewy012]

Might also be IAC valve, on top/driver side of the intake manifold.

Take a can of ether and check for a vac. Leak.

Plugged air filter?

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[JaneTheRockJohnson]

Might also be IAC valve, on top/driver side of the intake manifold.

Take a can of ether and check for a vac. Leak.

Plugged air filter?

Sent from my XT1254 using Tapatalk

Thanks for the additional tips. I got some Throttle Body cleaner and was gonna use that on the IAC valve (unless that's a bad idea? The Chilton manual says not to soak the IAC valve in any liquid cleaner, as it's an electrical component, but I'm not sure if that means I just can't use any liquid cleaner at all), and also some MAF sensor cleaner, and a new air filter. Don't think it's a vacuum leak cuz I don't hear any whistling, but I could check.

 

[chewy012]

I've heard the intakes have a special coating that gets ruined if you use cleaners like brake clean etc. But I used them and had no problems.

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[JaneTheRockJohnson]

Cleaned the MAF sensor and replaced the air filter today. I found some weird little rubber cap just floating around in the air filter housing. I'm assuming it could be the culprit, and have noooo idea how it got in there (probably from the last person who changed the air filter). Still gonna follow through with the rest of the cleaning I had planned, but I'd be surprised if taking out that little rubber thing didnt' do the trick.