Can't speed past 65

TMX

New Member
May 24, 2005
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Houston
Early I had some problems with hesitation under 2500rpms, turns out there was very low compression due to burned valves. I also suspected the fuel pump had issues as the fuel pressure wasn't very constant, but it still held atleast 33lbs which can hold the car running. Now that I have the head rebuild and everything back on, I was driving a friend around, got on the freeway to go home and was speeding up to 75mph. The car shifted into 3rd gear, then hit 3000rpms and would NOT go any higher, and the speed would barely inch it's way upto 70. MAF and TP sensors have good readings, new air filter, no leaks in manifolds and cat looks fine with good flow out the tailpipe so airflow does not seem to be an issue. Does anyone else think it's a fuel pump before I spend $100 on one, install it and pray that's what it was?

It's a 1993 2.3L N/A (obviously), fuel pump is probably a good 5-10 years old, fuel filter is farely new, injectors could need some cleaning, not sure.
 
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Forgot to mention it's an automatic, but I hoped it was assumed seeing as how "the car shifted".
At a complete stop, there is a slight hesitation then kind of a jerk like power just hit. If I'm just driving around, 2nd or low 3rd is no problem at all, it's just at 65mph in 3rd gear it will not go past 3200rpms. I took it to my dad's shop because he has all those ASE certifications in just about everything for cars, and he believes it's the fuel pump. Just by what it did last time the pump died and his other experiances in the field, but this is the only Ford 2.3 he has worked on. Oil pressure is good, near full tank of gas, engine never runs hot even though it is like 98+°F with the heat index and 60+% humidity (I swear I love this engine), new ICM, timing was verified as the engine was being reassembled. It got a full tune up about a month and a half ago, and I really don't drive far, so probably only a couple hundred miles if even since then.
 
Checked the throttle position sensor to see if its in range?

Fuel pressure with the vaccum line off should be 39ish.

rail should hold pressure after the car is shut off for about 5-10 mins, dropping very slowly after that.

I dont really see how the fuel pump would hold it to EXACTLY 3000 rpm....does it go past 3000rpm in any other gear? sounds kinda like a tranny /or/ computer limiting problem to me.
 
I'll get it on some lifters and check the connections and the tranny, it's just odd it has never done it before. And it really doesn't stop dead at 3000, it kind of wavers up and down and it's possible it keeps going down, but when it just stopped I didn't really push it, I just got off the freeway and went 55mph home. Tried it again on an empty stretch and same thing. Fuel pressure was checked at the vacuum line to be 30-32lbs, when revving it it'll goto about 35lbs, drop to 25lbs when you let off, then waver between at 30-32lbs. Almost doesn't make sense how it's only in 3rd gear, can't ever get to 4th gear. But on a long, desolate stretch I can get it to 85 and that's it. I know this thing goes faster, even though the speedometer is 85mph, on a mile strip its shifted into 4th when the speedometer stopped.

I might try to follow my book and run some electrical tests on the pump, sensors and check to make sure they are all plugged in. Unless ford had an AI that doesn't want me going faster that 65 any more or a part has some issues, I'm only lost.
 
Hmm, it very well could be. I noticed a small crack in the primary coil pack, there was no codes, but it could be failing just enough that it's not noticing really. The $40 for the coil packs is alot easier than a fuel pump, so it's worth a try. I also suspect there is something wrong with the throttle possition sensor or plate because I can't get it into WOT.