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1993 5.0 LX w/ 15k Miles.....No Power

Sheriff01

New Member
just got this beautiful black 93 5.0 5 speed with 15k original miles.....the car inside and out is pristine as is the underneath and engine bay. The exhaust and engine are 100% stock and factory original other than a K&N air filter.

Although I do have some gremlins.....here Are my issues.

1. very hard to start...takes 2-4 attempts...once it catches it idles well with no issues.
2. under normal driving it’s drives decent, few small stumbles at most but regardless if slowly accelerating or hard on the throttle, the car hits a wall at 3000rpms and falls flat and won’t go above 3500 rpms. It has zero real power and has the feel of something with a governor on it.
3. exhaust is stock and 28 years old... wonder if the the cats/ muffler may be clogging as it doesn’t have the old rumble I remember from back in the day.
4. no engine check light.

What I looked at so far

1. the air filter was clean as was the throttle body....I need to check to make sure it’s opening fully.
2. got new super unleaded gas in and I added some injector cleaner just to see what it would do

While I’m going to do some mods in the near future, I’d like to ensure it runs well before moving on. Although the mods may find my culprit.

My plan for this car is ——


1. Cobra Intake /Manifold
2. BKK 65mm TB
3. BKK CAI
4. BKK MAF
5. FRRP 19 lbs Injectors
6. 130 Amp Alt
7. Ford Racing 3.55 gears
8. GT 40 Heads w/ 1.7 RR
10. Dual Exhaust with Flowmasters ....maybe just 2 hi-flow cats if any.
 
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Sheriff01

New Member
Just ran codes with a reader.......

Key Off - 11
Key On - 12 ( Idle RPMs Out Of Range / High)

Ran both test twice to verify.
 

broncojunkie

Well-Known Member
Sounds like you may need a throttle position sensor, according to your code. There are some tests you can do with a meter. A quick googleberry search and you'll find a write-up on testing. If yours tests ok, I wouldn't change it. The newer aftermarket replacements aren't the best.

If that doesn't fix your low-power issue, take a look at fuel. I would start by checking fuel pressure and changing the fuel filter. A clogged filter could do it or the sock strainer on the pump pick-up in the tank. When you pull off the old filter, see if any nasty stuff comes out of the inlet side. It might tell you if you have rust or dirt in the tank.
 

Sheriff01

New Member
So.... been tinkering today.

tested fuel pressure

Key On - 0
Running -21
Removing Vac Line - 21 no change
Thumb over hole - 21 no change
When I turn car off... pressure drops steady to 10 then falls to zero quick

I changed the fuel filter ..... same numbers. Gas that came out was clean

I bit the bullet and changed to Fuel Pressure Regulator..... what bitch!!!! Same exact numbers !!!!!!!!! I definitely have a fuel pressure problem somewhere.

all that’s left is the pump in the tank ????



I tested the the tester on my truck and it read it correctly so the pressure tester is working properly.
 

broncojunkie

Well-Known Member
Sure sounds like your pump. Is it excessively noisy or making any odd sounds? Sometimes you can hear them going bad. When you drop the tank, you can see what it looks like inside. Old fuel can gum things up pretty bad. The tanks tend to develop rust inside. I had to replace my pump and tank. You should have seen it. Pump and hanger looked like it came from the titanic lol!

A parts store had the pump a few years ago....Autozone, iirc. The price of the pump and hanger assembly together was cheaper than just the pump by itself. My local Advance had the tank in stock for around $100. No-brainer. I should have bought 2. I'm guessing that was 5 or 6 yrs ago. I'm not sure how available these parts are now. They're getting harder to find locally.
 

broncojunkie

Well-Known Member
Found the pic. Of course, this car was not in running condition lol
20140512_145532.jpg
 

Sheriff01

New Member
Got everything I need so I’m gonna drop the tank and replace the pump and sending unit since I’m already in there. I sure hope this ends up being my problem!!!
 

Sheriff01

New Member
Busy day!!!! It was indeed a split line in the pump.

1. replaced fuel pump/ mount and new sending unit

2. BBK mid H Pipe with Hi-Flow Cats

3.BBK Ceramic Headers

4. Flowmaster American Thunder CatBack with polishes tips

Car sounds amazing and runs like a champ. I of course kept all the original parts and hardware. Thanks for all the help and advice. Think I’ve decided to keep the car pretty much stock except for 3.73 gears and exhaust as it’s so nice and original.
 

broncojunkie

Well-Known Member
Glad to hear that's all it was! And yes, there's definitely something to say about a stock fox. They're getting harder to find. That's why you see the unmolested cars bringing so much!
 
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