On the weekends I usually take a three hour drive back home, and during the trip the car will turn off like a switch. It has been doing this for the past two and a half months, always within a half mile of getting off the highway. Once it dies I try to recrank it but it won't fire up and have to wait a while before it does. No check engine light is coming on and I've already pretty much checked or replaced everything. The whole fuel system is good and working at 45-50 psi. I'm running the ltcc setup which got rid of the icm and the high volt side of the opti, which I have replaced. The weird thing about it is, on short drives no matter how I drive it, it acts fine. But on the ones goin back home it has died within the same 20 ft for the last three weekends. This has been since it's got cooler outside but when it's hot, the car will mis and smoke rich. But as soon as it dies it will crank right back up and go maybe a mile before the cycle starts over. I have never seen this kind of problem before inwhich it dies differently depending on the temp outside. I've rarely been able to get ahold of Bob Bailey who created this ignition but he says he has no clue about it. So I'm about ready to push it off a cliff and claim insurance lol. But if anyone has the slightest clue as to what this grimlen is, please let me know

Thanks, Adam

 

Fuel gauge taped on the windshield and reinact the whole scene. you may have 45-50 psi at idle/running but you never know when the fuel pump can intermittently take a crap. Also you're saying it runs like **** and smokes, etc. Could possibly be an egr getting stuck.

my .2

-Mario

 

Scan it for codes and let me know what codes you have. I'll have a clear answer for you then.

 

If it was losing fuel pressure wouldn't it stumble and die everytime? it would only stumble then die when it was 90-100 degrees this summer but now that it's gotten cooler it just turns off like if you did it with the key. And when it dies I'm ususally only at 10-15% throttle if not idle. But the egr has been removed

 

Oh and there isn't any codes

 

Check the coolant temp sensor on the waterpump.

 

It sounds like the fuel pump is overheating and won't operate until it cools down. Have you ever changed the pump? If so, did you reuse the fuel pump bucket? I would get a fuel pressure gauge, tape it to the windshield, take the vacuum off the FPR, tool around until it acts up again to see what your fuel pressure is doing.

 

Yep, I've replaced the waterpump's temp sensor and a buddy of mine put in a walboro 255 for me, but I don't know if he changed the bucket

 

You should look into that. How much fuel is in the tank when it starts acting up? Reason I ask is if the pump does not retain the bucket then it does not stay submerged once the fuel level gets to a certain point, the pump won't cool and its life can be dramatically shortened. The bucket is there to keep the pump in fuel no matter the level of the tank. I'd definitely get a fuel pressure gauge and see what's happening.

 

Then I would have to go with fuel pump. Mine would be fine on short trips then it would die after 5-10 minutes. Hook a fuel pressure gauge up to it as soon as it happens.

 

I had this SAME exact issue on my car for over a year. since i did not drive the car far it would act fixed after we messed with it, But when we did drive it a farther distance the issue would pop back up again. and i had a gauge on it one day when it started doing it. pressure was great and then started going down hill very fast. So like anyone would do i pulled the tank and got a new walbro 255 installed. after a long trip with the new pump it did it yet again. Everyone said it had to be a bad pump. well i did not think so i was saying no way its the pump. but i changed it anyway since 20+ yr techs said i was wrong and they had more experiance. well after 3 pumps i started to think i was correct. i got the car to act up and i pulled the FUEL PUMP connector at the rear of the car and omd the wires as well as verified proper voltage. now i had a "hot wire" kit on my car and still had plenty of voltage. well this left 2 cases, a plugged line, or bad pump...... well i finaly found out what was happing when i went to install my next pump, the vent tube from the pump was pinched from the First installed FP and after time the pressure in the tank was causeing the pump to shut down and flow very little. after an 30- 1 hr wait it would fire right up like nothing. Now if i new that was the problem i would have just removed my fuel cap and went on my way.


Not saying this is or is not your problem. i just wanted to share a issure i had that was very simular to yours. Use this info to help diag yours or point you in a good direction. but without verifying you have Correct pressure when its failing it will be tough. fuel pumps are funny sometimes they wont work at all and other times they will work than die and then work again. even 1 psi under spec can cause problems.

 

When it acts up it still usually has about half a tank. But the vent issue sounds pretty possible since I replaced the pump under a year ago, but does it make sense for it to just randomly start acting up the one day or did you see signs or issues somethin was actin up?

 

And could this be why the cap hisses loudly when i'm about to fill it up?

 

I had the same issue that wouldnt go away, i chased it for months (alot of guys on here know, they were a huge help ), then the only possibility left (the 2 year old accel opti that came with the car) needed to be replaced, on my way to the opti i found the issue. The long cavity plug that goes into the opti was discombobulated, to say the least, only 3 of the 4 connectors were touching, the one corner was snapped, and it was corroded beyond belief. I replaced it and its been purring like a kitten ever since. Good luck to you.

LT1's are like women who are golddiggers, you keep buying them new stuff, but their never happy

 

I've already looked all over from the opti to the gas tank an nothing looks out of place, broken, or leaking so I'm pretty much stuck

 

Yes. Many people, including myself have had pumps go out after only a year. You are not stuck. Get a fuel pressure gauge, take vacuum off FPR, go drive around and see what happens. Your pressure should stay at a steady 43 to 45psi (factory spec is 43.5). If it goes below this, no matter the behavior of your driving, the fuel pump is most likely going bad.

 

yes the tank would almost gasp when you removed the cap. The only way to verify this problem is with a FPG hooked up during the issue in question. it took my car almost 2 hrs to start stalling out before i could verify.

And unless you drove my car for a long time then it would run PERFECT. i ran a 11.13 with a 200 shot on a stock short block during this issue. at the time i thought all was good then 2 days later drove 2 hrs to orlando and it dies on freeway.

This vernt thing cought me off gaurd and everyone blames the opti everytime something is wrong with an lt1...... i have a autozone opti right now and have had it on 3 diffrent blocks and it has seen 7400rpm and works great. So with everything electrical some are great and some are ****.... nothing is perfect everytime

 

So how would I go about hooking up a fuel pressure gauge so that I can read it while driving? Or is the line long enough?

 

Mine did the exact same thing and was the fuel pump. Replaced it and it was perfect. I had good pressure and it would just go out. After about a half hour it would start and run again. I 2nd checking it with a gauge. Good Luck

 

You need to get yourself a Haynes manual or equivalent. Shoebox also has great info on his page: www.shbox.com
There is what's called a Schraeder valve located on the fuel rail on the back side of the intake. You can screw a fuel pressure gauge to that. It will be long enough to go around the cowl and onto your windshield.