Everyone,

I have a 93 with 138,000 miles and things are starting to act a bit strange. THis morning, I had almost no power down low. Then after
5 secs of puttering along, it took off as normal. After driving like this for 10 minutes, the Check Engine light came on.

The truck continued the lack of power down low, and the Check Engine light would stay on for about 5 min, go off, and come back on.

BTW, the truck still runs strong. No pinging or anything. The only other weird thing happening is that when I run the AC on a hot(95+) day, the temp gauge gets real flaky. Pulses high/low in a very quick timeframe. It's not the thermostat opening up. The needle just randomly moves around a given area for about 10 seconds and then stops. While it does this, the truck does hesitate.

Any ideas would be greatly appreciated.

Thanks

------------------
Brian K
kimmel_brian@prc.com
thedink@ix.netcom.com

99.5 Black - Born 5/17/99

• Tinted Windows
• PSP Intake
• Clear Corners
• Autometer "Phantom" Boost Gauge
• SuperChip "FlipChip"
• Bedrug
• Alpine Audio w/MB Quarts all around
• Tow Package
• Mobil 1

93 Black Daily Driver:

• Bolt ons & Faded Paint

 

Very simple very easy to fix.When there is check engine light,it is some kind of a sensor gone.Have it put on a computer.The guages are probally just old.There is no way the temp fluctuates that much in a short time period.Write that off to a old guage.To me it sounds like a cold start sensor,It is a very common problem for 93-95 f150s.

 

The senor is more than likley correct but also check for a fuel filter or some garbage in your tank thats blocking the fuel pick up.

------------------
1999 Red SVT Lightning
#3466 of 4000
NLOC #428
99 Grand Prix GTP Red

 

Definately check the code. My check engine lite only came on once on my 93 and it turned out to be a ruptured diaphram in the fuel pressure regulator which if left unfixed could fill the engine with gas causing fluid lock. Bad news. They replaced the reg. and mine never came on again.
noelvm

 

OK, I just ran the codes and they are:

118 & 173

Any ideas from here??

Thanks

Brian K
99 L
93 L

 

Did you check the dilithium crystals or the flux capacitor? Mine gave me problems until I had the engine transmogified. Check with Spock or Scotty.

 

Hey Brian, Sal here. The 118 code means the ECT (engine coolant temp) sensor is showing a voltage above it's maximum range. That makes the PCM think it's -40 all the time. The 173 is the result of the motor running super rich from the ECT being screwed up. Replace the ECT and you should be okay.

------------------
SAL - TEAM PSP
Best ET 13.09 Best MPH 104.58mph Best 60ft 1.87
Power Surge Performance 99 Lightning Chip and Filter Kit, full Bassani Exhaust, M/T ET Streets PowerSurgePerf@aol.com

 

Everyone,

I replaced the ECT and that fixed the check engine light and the moving temp gauge. I still have no power down low.

I ran some fuel pressure tests last night. Key on engine off the pressure was struggling to stay at 30. Bouncing between 28 & 30. As per my fine chiltons book, the pressure should be 30-45. Removing the vaccumm from the pressure regulator did put it at about 40.

I picked up a new fuel filter last night, I will install that this morning.

I am kind of ruling out the pumps because the problem happens with both tanks, and there is no weird noises coming from the tank(s). Anyway, I have tried 2 different gases, and that doesn't seem to be the problem.

Anyone have any ideas about testing the fuel pressure regulator??? I actually have one of the downs adjustable regulators new in the garage, so I can change it out if needed.

Again, any help is appreciated,



------------------
Brian K
kimmel_brian@prc.com
thedink@ix.netcom.com

99.5 Black - Born 5/17/99

• Tinted Windows
• PSP Intake
• Clear Corners
• Autometer "Phantom" Boost Gauge
• SuperChip "FlipChip"
• Bedrug
• Alpine Audio w/MB Quarts all around
• Tow Package
• Mobil 1

93 Black Daily Driver:

• Bolt ons & Faded Paint

 

Hey Brian, Sal here. You should have about 39-42 psi (spec is 39) with the engine running and the vacuum line OFF. That's your base fuel pressure. With the vacuum line ON, it will drop to under 30, because fuel prssure will drop about 1 psi for every inch of vaccum. What you really need to see, is what your fuel pressure is doing under load, when the truck acts up. You will need a gauge that you can tape to the windshield to watch. Under heavy accelleration, there will be no vacuum and pressure should return to base setting (39-42). Also make sure your plug didn't foul from the bad ETC.

------------------
SAL - TEAM PSP
Best ET 13.09 Best MPH 104.58mph Best 60ft 1.87
Power Surge Performance 99 Lightning Chip and Filter Kit, full Bassani Exhaust, M/T ET Streets PowerSurgePerf@aol.com

 

Sal,

I just finished the fuel filter install. It still has the same problem. After starting, it idles fine(Very smooth), but when I try to take off, it just boggs down. A couple seconds later, it takes off like normal.

I did a couple road tests, and it seems that after it gets warmed up, the problem goes away. Even after sitting idle, the problem was gone.

This same type thing happened before and the dealer put a new regulator in. I am wondering if installing the Downs adjustable is worth the effort??

Unfortunately, my fuel pressure gauge has only about a 1.5' hose on it. There is no way it will stretch out to the winshield. I guess I could pick up an extension from the local trak auto and see if that works out.

Let me know if you think installing the regulator is worth it. Looks like a b&^ch to install.

Thanks

Brian K
99 L
93 L

 

Check your TPS(throttle position sensor). When bad it can cause symtoms similar to a bad accelerator pump. Just a thought.