Rpm Drops After Driving For A While? What Is It And How To Fix It?

[t-roy707]

I Make Constant 200 Mile Trips Back And Forth. After About 150 Miles (especially Driving Up Hill) The "check Engine" Light Turns On And Moments After My Rpm Drops To Where Even If Im Flooring The Gas, The Rpm Remains Very Low, And Not Going Fast At All. I Have To Do About 45mph On A Hill I Normally Do 65mph Without This Problem. Can Anyone Help. I Was Told It Was Probably Fuel Pressure Probs. I Was Just Going To Replace My Fuel Pump Hoping It Would Fix This. Any Help Would Be Great. Thanks For Reading

 

[metstalker]

i would wait on the fuel pump its rather expensive 350 to have replaced... make sure its that before trading parts out. if the check engine light turns on is there a chance you could pull the codes or does it not stay on for long. could be a short somewhere causing the problem.

 

[metstalker]

ohh and make sure all the spark plug wires are plugged in tightly. i would lose rpms when a cylinder would miss because of that

 

[marragtop]

The codes should be stored even if the light goes out. Pull the codes and see what they say.

 

[witchdoctor]

could also be clogged cats

 

[savagefan]

Pull codes and post results here before throwing money at the partsman.

 

[walterd140]

Mine did the same thing until I cleaned the Mass Air Flow sensor (MAF). It's located right after the air cleaner & you need a secure torx 20 (those funny hex wrenches, but with a hole in the middle). I got one at Autozone for $9.99 (about 8 came in a set), I am told you could try a computer repair place as this type of screw is used in computer power supplies.
Anyway, remove it & clean with some contact spray & q-tips. There's a great 'how to' over in the maintance reference section. Here's the link

http://www.explorerforum.com/Singleton/web/pages/ping.html

Good luck
Walter

 

[Rhett]

Pull the code like everyone says. It could be 1000 different things--stretched throttle cable, bad wires, bad fuel pump, dirty MAF, bad relay, bad FPR, vac leak, clogged cat, worn out TPS....etc etc etc

 

[Glacier991]

[Sigh] The computer is just waiting to tell you exactly what system is causing the problem and people are guessing at it? Pull the codes. Please.

 

[t-roy707]

ok. ok. im gonna pull the codes. the thing is, out here they don't rent out "OBD I"'s. i have to buy it and it's like fourty bucks!!!!! i'll probably only use it like twice in the life time of my "X" and i could possibly lose it in time. but have patience i will pull the codes if i have to buy the damn thing. thanks guys

 

[Glacier991]

Actually, you do not need a tool to pull the OBD-I codes. All you need is a paper clip or similar jumper wire. In the Under the Hood sub forum on Auto Computers, under EEC-IV there is a thread on how to do it. Posted for about the 500th time.

 

[nascar_intimid]

Pull codes and post results here before throwing money at the partsman.

well said!!!

 

[inh]

mine did this one night. the computer decided to shift in to overdrive at about 40 mph... disconnected the neg battery cable overnight, reconnected in the morning, no problem since!

 

[walterd140]

You guys have an Autozone out in Nevada? If so, they will pull the codes for free. I'm not sure if the light has to be constant or if they can get it from the memory, but for free, it's worth a try......

In a pinch, clean the mass airflow sensor. Takes about 20 minutes, 10 q-tips, 4 squirts of contact cleaner. You will need a torx 20 secure (hole in the middle) star hex wrench (Radio shack should have it, got mine at Autozone in a kit for $10). Anyway, that solved my issue. If it is not your problem, it should be done anyway as a new one starts at $60 & goes up. It is basically 2 offset heightwise wire filiment looking things that read whatever. Unless the wire between the posts are broke, why not clean instead of replace?