02 Ford Lightning Running Issues... HELP!

decepts

decepts

Member
Early this year I took my ford to the ford dealership to troubleshoot my running issues. Around $2k later I had the ECU, sparkplug and a coil replaced and then they were telling me I had a fuel pressure issues and wanted to replace my fuel pump. I told them I just replaced it a few years back so I took the truck back home and replaced the fuel pumps with two Walbros 255lph pumps replaced the Y connector with a stainless steel one and put everything back together. I checked the fuel pressure and currently read around 30 psi. Stock levels should be around 35-45... So I put my fuel pressure gauge right after the fuel filter and pinched off the line and read around 60 psi. So I got good pressure. I then hook up my fuel pressure gauge on my fuel rail and I pinch off my return line by my fuel filter and I get around 60 psi. When I let everything flow without pinching my line anywhere I get around 30 psi. Which tells me the fuel regulator (stock and another new stock one) is regulating at 30 psi. The only way I can change this is get an adjustable regulator. So I then decided to check my hi / low fuel pump relay; which is good. I then hot wired it to run all the time and I now get 60 psi all the time (this jumper I later removed since after all this doesn’t seem to be the problem). So now I really don't have a fuel pressure issue anymore but my truck acts just the same before doing all of this still. WTF?!

The problem I'm having is that it is very gutless when going up hills and when I want to get on it. It wants to "pop" or "choke" out especially right before it goes into the next gear if I want it to kick down by putting my foot in it more. Can anyone please give me some ideas on what is going on? Any information would be great!

Thanks!

---------- Post added 05-28-2012 at 09:30 PM ----------

Update:

I've noticed today while running some tests and graphs that my timing retards in response to giving it some throttle. WTF?! I know that the timing should advance while giving throttle but this isn't the case for my 02 Lightning. Can anyone please give me some ideas and thoughts on why this might be? Thanks!
 
One thing comes to mind with your description, intercooler pump not working. Check for flow when warmed up, pop the cap and look inside you should see fluid moving. The items to also be checked, the ceramic resistor by the intercooler pump and then just replace both fuel relays, these have a tendency to stick. I highly doubt the stock regulator is bad, it can happen just not a common theme.

On my '02, the fuel pressure has always been around 28-32 in normal running conditions, goes to over 50 while in boost under load.

What is your mod list, how many miles, and what was the last thing you did before the problem was noticed the first time.
 
fuel

you might want to check the high pressure fuel relay @ idle power for fuel pumps run through a resistor at boost the relay supplies full power
Mitch
 
Sounds like your intercooler pump is dead. If the IAT2 temps reach 150* and higher the computer starts retarding the timing. The higher the temps the more timing it pulls out. The pump is located behind the heat exchanger in the bumper.
 
Thank you guys for your replies! Last night I was working on the truck until 12:30pm... Here is what we did. We pulled the fuel line from the fuel filter and checked flow. I am getting around 4.25 gallons a min.... Then we pulled the upstream and downstream fuel lines off the fuel rail and blew air through them with a white cloth at the other end to see if anything might come out other than gas and to see if we are having any kind of flow issues. Everything appeared to look fine and the air flow was great. So then we hooked up the upstream fuel line back to the fuel rail and pulled the fuel pressure regulator then blew from the fuel line just after the fuel filter down the fuel line into the fuel rail and flow appeared to feel and sound good. Then we put the fuel pressure regulator back in and then connected the return fuel line back to the fuel rail and blew air into the fuel line just after the fuel filter and we would get air pressure (at this time I also had the fuel pressure gauge installed on the fuel rail) around 65 psi and then the air would drop to around 40 psi which is correct for the fuel pressure regulator is rated for that and then we would get some air back at the end of the return line. So the whole fuel system other than the injectors have great flow and did not have any junk come out of them. So we then decided to just hook everything back up and start the truck. The truck started right away and sounded awesome. So we decided to take it down the road and it would run just fine before we would get into boost. Right when we were getting into boost it would hesitate so I just kept on driving for about 10 miles avoiding boost and the truck would run fine! This was not the case before. Also all this time I had the fuel pressure gauge hooked up and in my window and I was holding steady 37 psi which is also within spec. (35-45 psi is what book is). So I decided to take it for a longer drive and with all said and done I am now able to get up to around 4-5 psi of boost before hesitation. So we did something to at least get a change.

In response to the intercooler pump I don’t think that this is the case for I am getting this problem cold and hot but I will double check for flow. In regards to the fuel relays they both are working fine and this was shown one by fuel pressure and another when I get on the throttle I can see the fuel pressure go up 60+ psi which I know is the second pump kicking on. I also before did run some tests on them and they tested ok.

So now this leads me to this question… My truck has a smaller upper pulley and a larger lower pulley. My ECU was replaced by Ford because they could not re-flash my old ECU. Now I’m guessing that the reason why the ECU was locked down is because it might have been tuned. Question now is can the stock ECU handle the super charger change in boost pressure etc? My thought is that the stock ECU with the change in pulleys for the supercharger may not know what to do with the higher boost pressure and it is going off the map and therefore cutting fuel as a safety. Any ideas on this thought? My other idea is that I might have a gummed up fuel injector and that might be causing the problem. For this I was just going to go out and fill my tank up half way and put some seafoam in the fuel tank.

Anyhow sorry for the long book I wrote there but I figured I’d give some more insight on what was done and where I am now. Please let me know what you think. Thanks!
 
The stock tune can safely adjust for up to 4 psi more boost over stock but it isn't the best practice, should have a proper custom tune.

To check fuel pressure - connect a mechanical gauge to the schrader port on the fuel rail, remove and plug the vacuum reference line on the regulator, at idle the fuel pressure should be 40 psi. Is the check engine light coming on or are there any codes? You need to check the TPS and make sure it's adjusted and reading properly. What spark plugs do you have and what are they gapped to?

FYI, spark decreases as RPM and load (airflow) increase. Idle spark is much higher than WOT at 4-5K RPM. List everything that has been done modification wise also, it helps.
 
That’s good to know about the stock tune so at least I should get this to safely boost completely without falling on its face. So that eliminates that possibility. The fuel pressure has been tested and is good now after replacing the pumps with two Walbros 255LPH pumps with the stainless steel Y fitting etc. In regards to a check engine light I have no pending codes or any codes at all so no check engine light. The TPS according to my reader is around 19% at idle and this has been like that before the truck starting running bad. Now is there a way to adjust this so it is more around 1% or what not? I am not aware that you can even adjust this. The spark plugs are brand new and are the ford motorcraft brand which were gaped to the stock gap of .052-.056.

From what I was reading that a general rule of 1 pound of boost 1 degree retard. So 4 pounds of boost 4 degrees retarded. Which I didn’t know at the time… Here is what I currently know about my truck:
Smaller upper pulley, larger lower pulley, oval butterfly valve on throttle body, cold air intake, exhaust with cat deleted, two Walbro 255LPH pumps with stainless Y fitting, it appears that it was chipped in the past but may have been taken in to be tuned for the ECU was locked and Ford replaced ECU with new so back to stock. From what I was told but I can’t tell you for sure that the previous owner spent around 10k in motor work but I cannot prove this for I honestly can’t see where this money is for it appears that the fuel rail is stock and injectors and cops are stock so if this was true then why aren’t theses upgraded. So are far as I currently know above is what was done. Also there is only around 73K miles on the truck.
 
Close the plug gap down sounds to me like it is blowing the spark out. I am no gen2 guru but I know that u should close the gap when upping the boost. Id set um at about .045 n see what happens.
 
You need a tune!!! Smaller upper and larger lower means it had a tune. You said it looked to have a chip installed in the ecu that Ford replaced. You are probably trying to run 6lb's of extra boost with the stock tune. Plugs need to be gapped to around .035. I would swap to tr-6 plugs.
 
decepts said:
The spark plugs are brand new and are the ford motorcraft brand which were gaped to the stock gap of .052-.056.
Click to expand...

There is your problem. You need some NGK TR6 plugs (part number 4177) gapped to .038" and it'll run like new.

Without knowing what all else has been done that's the best guess I can give.
 
NGK TR-6 Plugs gapped to .035-.038 will probably solve most of your issues.

However, maybe somebody up there is watching out for you because if your engine is pullied as you say it is, you could well be up as high as 14-16 psi. One good WOT run on a stock tune and you could seriously damage your pistons.

MY ADVICE: drive it easy until you can get it properly tuned.

I'll be hoping that your next thread doesn't say you just joined the VBC.

Mike
 
Last edited:
Did you ever get this running correctly?? If not did you ever consider the check valve is bad in the gas tank.?? Mine is doing the same thing as yours it seems...
 
Gad. It's eight years later. The guy probably doesn't even have the truck anymore. He hasn't even logged into the site since June 2012. :cr:
 
Mikediddi said:
Did you ever get this running correctly?? If not did you ever consider the check valve is bad in the gas tank.?? Mine is doing the same thing as yours it seems...
Click to expand...

Mike, I think it would be best if you start a new thread with what's going on and what steps you've taken. Also a a description of your truck and any mods.
 
You must log in or register to reply here.
Back
Top