weird pulse??

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07-29-2008, 04:58 PM
ChevyLee

weird pulse??

The truck won't start on the first try when it has been sitting for a little bit. I have no idea why it does this, i replaced the FPR twice and it is still doing this..
Also when the truck is hot, i try to start it and it pulses at idle, if i put it in gear it dies. here is a small clip of the pulse, i dont know if its in the tune, allen re tuned it and it is still doing it so i have no clue. I know there was a bad batch of walbro 255 pumps going around, could that be my problem??
Also everything else seems OK...
http://i70.photobucket.com/albums/i1...k/th_weird.jpg
07-29-2008, 05:18 PM
COWL327

Sounds like its getting fuel when its setting.....it has to clear out.Rev it a little when you start it to clear it
07-29-2008, 05:29 PM
ChevyLee

Quote:

Originally Posted by COWL327

Sounds like its getting fuel when its setting.....it has to clear out.Rev it a little when you start it to clear it

just did that, an it clears it out for a few seconds but then pulses again... and still wont start on the first try :tantrum::tantrum::tantrum::tantrum::tantrum: :tantrum:
07-29-2008, 05:30 PM
RedHeartbeat

Bring it over and we'll figure out whats going on.
07-29-2008, 05:31 PM
ChevyLee

Quote:

Originally Posted by RedHeartbeat

Bring it over and we'll figure out whats going on.

Im leaving Saturday morning for dallas and not leaving until Sunday night or Monday :tacos:
07-29-2008, 05:34 PM
RedHeartbeat

Sounds like a plan.
07-29-2008, 05:37 PM
Ramsey

could be a dirty injector ,bad fuel pump.check your fuel pressure then drive down the rd with the gauge on youre windshield and see if it loses any.ive had terrible luck with warlboros,and refuse to use em .alot of guys like em but ill never use 1 again.check all of youre connection going to the throttle body also ,mine will act like that when ive blown a fitting of my s.c. going to the tb.process of elimination,check fuel pressure then let us know.
07-29-2008, 11:59 PM
txarkitekt

Looks as if it is a tuning issue to me...
07-30-2008, 12:10 AM
1slow02

what about a leaking fuel pressure regulater on the drivers side fuel rail have seen those fail numerous times
07-30-2008, 10:09 AM
ChevyLee

Quote:

Originally Posted by 1slow02

what about a leaking fuel pressure regulater on the drivers side fuel rail have seen those fail numerous times

replaced it twice. this video was taken about 1 hr after i put a new one in..

i have a feeling i have a bad 255 fuel pump..
07-30-2008, 11:13 AM
farmtruc

Quote:

Originally Posted by txarkitekt

Looks as if it is a tuning issue to me...

I doubt it, with a stock engine, there isn't any tuning needed at idle on his setup?

Ricky, get a fp gauge and check fp, it might be that. I've seen some walbros bleed down when the key is off.

Try this:

Turn the key to the ON position, then OFF, then ON, then OFF, then ON, now try to start it, did it do any better?

If so, you're allowing the fuel lines to build pressure before starting.

I'll check, but we should be able to warranty that pump out for you.

allen
07-30-2008, 02:02 PM
ChevyLee

Quote:

Originally Posted by farmtruc

I doubt it, with a stock engine, there isn't any tuning needed at idle on his setup?

Ricky, get a fp gauge and check fp, it might be that. I've seen some walbros bleed down when the key is off.

Try this:

Turn the key to the ON position, then OFF, then ON, then OFF, then ON, now try to start it, did it do any better?

If so, you're allowing the fuel lines to build pressure before starting.

I'll check, but we should be able to warranty that pump out for you.

allen

Allen,
Thats what I do to make it start up. Mind sending me a new unit? I will try an see if i can drop the tank today and try to test that fuel pump out. Thanks.
07-31-2008, 09:15 PM
ChevyLee

Got the new fuel pump, thank you Melissa and Allen. Going to slap it in tomorrow.

side note got my a/c all fixed up!
08-01-2008, 06:08 PM
ChevyLee

ok the pulse is still there, but it starts perfect now. yes the fuel pump was losing all its pressure, it had a leak.
08-01-2008, 06:17 PM
farmtruc

Quote:

Originally Posted by ChevyLee

ok the pulse is still there, but it starts perfect now. yes the fuel pump was losing all its pressure, it had a leak.

Might be time to hook a smoke machine to the engine and look for a vac leak.
08-04-2008, 04:30 PM
2500Ak

If that's the only symptom I'd hold the MAF or the IAC suspect. Is it throwing and codes? Might try cleaning the MAF, IAC and the throttle body with some electrical parts cleaner. When my MAF failed it behaved like that.