Starts but 10 seconds later she dies

[uae_lightning]

I recently overhauled the lightnings engine. when I start up the truck, it idles for about 10 seconds and then just dies. I am sure its not the tune.

The fuel pressure goes way low and it dies.. So I wired the fuelpumps direct just to check and it idles for 10 seconds then a check engine turns up and the car dies. It wont let me read whats the Trouble code.

Any Ideas n whats the problem ?

Thanks.

 

[SID297]

Are you sure you plugged everything back in? Did you change anything other than swapping the engine?

 

[whobock]

Are you sure you plugged everything back in? Did you change anything other than swapping the engine?

this^
definetely need more info. list of mods so on. make sure all electrical connections are clipped on and tight. dont forget the mass and idle air. all of em. check all vaccum lines to make sure there are no vaccum leaks.

 

[uae_lightning]

Mods :
TFS 44CC HEADS
Built shortblock with 9.2:1 CR
Crower Stage 4 cams
4LB Lower
SCT BA3000 MAF sensor
Base tune is made for the mods...

At first I had a problem with the cam timing and a broken chain tensioner, but then I fixed everything and evertyhing is plugged in and triple checked..

the problem is.. it runs for 15 seconds and then there is a fuel pressure drop and the truck dies..

 

[chrisheltra]

So you get a CEL and your programmer doesnt show a code?

 

[uae_lightning]

No code..

 

[Ct.TOPGUN]

Stage 4 Crowers and TFS heads. Why are you so sure the tune is good? That is a unique combo.

Jim

 

[gtjoe]

Fuel problems?

 

[PhLoBuS]

vacuum lines in the correct spots?

 

[mifordman]

does it start right back up?
will it run for longer off idle?

 

[whobock]

does it start right back up?
will it run for longer off idle?

^this^


have you tried to sit in the truck and keep it running by using the gas pedal. i would try that first. if it keeps running with you working the pedal its not gonna be a pump issue. if thats the case id check all vaccum lines(cheapest thing) and work from there. if they are not all connected or if you have 1 leak the truck wont idle. i just had this problem with mine after i did the egr delete. i forgot to cap off 1 line and the truck would not idle. going down the road was ok but idle, no.
if it runs working the pedal. get a can of start fluid, work the tb with one hand(to keep it running) and spray the start fluid all over the lines and intake, tb etc. listen for the rpm to raise. if it does youve found your problem.

 

[uae_lightning]

does it start right back up?
will it run for longer off idle?

Starts back upp after 2 tries


I also checked the for vacuum leaks maybe 5 or 6 times... I also took readings and sent my own tune to some professional tuners who said it should run like that.. They also tried to tweak the tune a bit more.. BUT SAME PROBLEM...

 

[badmercs]

fuel pump resistor plugged in?

 

[XSIVHP]

Check your trans harness, when my engine was put back in, it was wedged between the headers and the firewall, ultimately crimping and shorting some wires out. Just a thought.

 

[Robert Francis]

I would assume that the "base tune" you refer to is set up for the SCT BA3000?

 

[Canadian_Bacon]

There is a small bypass tube running off the air cleaner elbow to the intake. make sure the rubber boots are intact and not leaking. I had to replace the tube last year when I had the same sort of problem.

 

[sik2000]

Is your Theft light in the dash flashing at all