Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

well... the sub is running again but i got a problem

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by muddysub, Jan 24, 2005.

  1. muddysub

    muddysub 1 ton suburban status Staff Member Moderator GMOTM Winner

    Joined:
    Jun 23, 2001
    Posts:
    10,452
    Likes Received:
    489
    Location:
    my garage, Henderson, NV
    well yesterday, after almost 2yrs, the suburban fired up... i rebuilt the TBI, replaced the injectors, replaced the fuel pump and filters... i got oil pressure immediately, and everything loks good. but it idles rough, kinda lopes, and once you put it in gear it falls on its face. it barely moves under its own power, and the RPMs lope really bad, sounds like its gonna stall about every 5-10 seconds. i plan on putting a cap, rotor, wires and plugs in it son but i dont think its an ignition problem... the IAC hose broke and i put it back together with electrical tape, so that might be leaking... bgut any other ideas as to why its idling like hell?
     
  2. 88sub4x4

    88sub4x4 1/2 ton status

    Joined:
    Sep 22, 2002
    Posts:
    792
    Likes Received:
    0
    Location:
    Long Island, NY
    Make sure nothing made a nest in your exhaust. Even if it revs up in neutral or park, it may still be partially clogged. Dodge trucks do this all the time when the cat goes bad and gets partially plugged.
    By the way, what ended up fixing the fuel problem that you had? Was it the pump?
     
  3. muddysub

    muddysub 1 ton suburban status Staff Member Moderator GMOTM Winner

    Joined:
    Jun 23, 2001
    Posts:
    10,452
    Likes Received:
    489
    Location:
    my garage, Henderson, NV
    yeah it was the pump... hmm ill drop the cat off of it and try it out. the cat is the only thing left in the exhaust system, all the rest fell off years ago...
     
  4. muddysub

    muddysub 1 ton suburban status Staff Member Moderator GMOTM Winner

    Joined:
    Jun 23, 2001
    Posts:
    10,452
    Likes Received:
    489
    Location:
    my garage, Henderson, NV
    yeah it was the pump... hmm ill drop the cat off of it and try it out. the cat is the only thing left in the exhaust system, all the rest fell off years ago...
     
  5. muddysub

    muddysub 1 ton suburban status Staff Member Moderator GMOTM Winner

    Joined:
    Jun 23, 2001
    Posts:
    10,452
    Likes Received:
    489
    Location:
    my garage, Henderson, NV
    you're kidding me right? its been like 4 or 5 days and ive only got one reply besides my own? come on i know someone on here can help me with this.
     
  6. BadDog

    BadDog SOL Staff Member Super Moderator Author

    Joined:
    Feb 24, 2001
    Posts:
    7,777
    Likes Received:
    11
    Location:
    Phoenix, AZ
    Still sounds like it might be fuel pressure problem. What is the line pressure? Could also be IAC, or some sensor. If the fuel pressure checks out (always the first thing to check) then hook up WinALDL or a hand scanner.
     
  7. Stoopalini

    Stoopalini 1/2 ton status

    Joined:
    Oct 17, 2000
    Posts:
    999
    Likes Received:
    0
    Location:
    Austin, Texas
    Have you checked for codes? If the "Check Engine" light is not on, check to be sure the bulb is good. When you turn the key to "On", the "Check Engine" light should come on and then go off after a few seconds.

    Did disconnecting the cat help at all?

    When you rebuilt the TBI, did you replace the IAC?

    I would definitely get it hooked up to WinALDL and see what's going on. WinALDL will show you mixture, IAC counts, TPS reading, detonation (if any), etc ....

    Thomas.
     
  8. muddysub

    muddysub 1 ton suburban status Staff Member Moderator GMOTM Winner

    Joined:
    Jun 23, 2001
    Posts:
    10,452
    Likes Received:
    489
    Location:
    my garage, Henderson, NV
    no the light is not on and the bulb is good... i didint replace the IAC. the exhaust is not the problem, i dont have a scanner but ill borrow one from a guy at work on monday.

    if it was a pressure problem wouldnt it effect it at higher RPMs? because the only problem is at idle...
     
  9. Stoopalini

    Stoopalini 1/2 ton status

    Joined:
    Oct 17, 2000
    Posts:
    999
    Likes Received:
    0
    Location:
    Austin, Texas
    Only problem is at idle? So when you start driving, it seems to run fine? If so, maybe one of your injectors is leaking. Start it up and watch the spray pattern from the injectors. If one of them is dripping, that's your problem.

    Thomas.
     
  10. heavy4x4

    heavy4x4 1/2 ton status

    Joined:
    Aug 28, 2002
    Posts:
    3,270
    Likes Received:
    0
    Location:
    Delafield, Wisconsin
    After that long of a sit, you need to do a full fluid change (coolant, tranny fluid, engine oil, and GAS!!! no way is gas that old going to be good at this point!) Also, pull a spark plug or two to check condition. This is a good time to check spark plug wire insulation for cracks.

    I guarantee that if your gasoline is 2 years old, REPLACING it (not adding fresh stuff to it) would get rid of 90% of your issues. I know you said you replaced filters too...I'm assuming you're including fuel filter in this, if not...it needs replacing as I'm sure that's gummed up with old gas.

    After you do these things, start up your 'burb and let it sit and run for a while (10 minutes or more). Give the engine time to "fix itself." If it's still having issues after that, it's time to replace sensors.

    Good luck...let us know how things go!

    P.S. Did I mention your old gas needs to be REPLACED?!?!:grin:
     
  11. muddysub

    muddysub 1 ton suburban status Staff Member Moderator GMOTM Winner

    Joined:
    Jun 23, 2001
    Posts:
    10,452
    Likes Received:
    489
    Location:
    my garage, Henderson, NV
    it is new gas, when i dropped the tank i got rid of the old gas and put 10gal of new stuff in it.
    and u cant start driving with it, as soon as u put a load on it ti falls on its face.
     
  12. muddysub

    muddysub 1 ton suburban status Staff Member Moderator GMOTM Winner

    Joined:
    Jun 23, 2001
    Posts:
    10,452
    Likes Received:
    489
    Location:
    my garage, Henderson, NV
    well i got it out on the road today!!!!! i let it warm up at about 1000-1200 RPMs for like 10 min and it ran ok, still felt cold, didnt like sudden throttle applications but it idled smoothly after a few min... im still gonna flush EVERY fluid on it and give it a new cap, set of wires and plugs and a new rotor...
     
  13. stallion85

    stallion85 1/2 ton status

    Joined:
    Jul 11, 2003
    Posts:
    3,659
    Likes Received:
    0
    Location:
    Cedar City, UT
    Scott, I hope all is running good in May. We need to get together again and do some Rock Crawlin:grin:
     
  14. 73k5blazer

    73k5blazer Unplug the matrix cable from the back of your head Premium Member

    Joined:
    Dec 28, 2001
    Posts:
    4,987
    Likes Received:
    38
    Location:
    The Rustbelt
    If your burb has an EGR valve, that might be bad. My '86 C10 would idle and run fine, until you put it in gear, then it would die. When I disconnected the vacuum line to the EGR valve, it started running and driving perfect again. Most people diconnect the vacuum line going to the EGR and plug it. That fixed my problem, but I actually replaced the thing, for reasons I'm still trying to figure out.
     
  15. muddysub

    muddysub 1 ton suburban status Staff Member Moderator GMOTM Winner

    Joined:
    Jun 23, 2001
    Posts:
    10,452
    Likes Received:
    489
    Location:
    my garage, Henderson, NV
    nope i dont have an EGR.... every time i start it and run it it gets better... its just not used to running yet, its pissed cuz i woke it up. lol. it idles fine now.
     
  16. muddysub

    muddysub 1 ton suburban status Staff Member Moderator GMOTM Winner

    Joined:
    Jun 23, 2001
    Posts:
    10,452
    Likes Received:
    489
    Location:
    my garage, Henderson, NV
    by may? no problem ill have my 4.56s done by then, we'll go out and see how she likes the rocks hehehee.
     

Share This Page