Jump to content
  • Sign up for FREE! Become a GM-Trucks.com Member Today!

    In 20 seconds you can become part of the worlds largest and oldest community discussing General Motors, Chevrolet and GMC branded pickups, crossovers, and SUVs. From buying research to owner support, join 1.5 MILLION GM Truck Enthusiasts every month who use GM-Trucks.com as a daily part of their ownership experience. 

Recommended Posts

I have a 1993 k3500 454 NV4500... The engine is a semi fresh rebuild(50K miles) with a small cam. I have replaced the following some parts multiple times...  The truck has a stumbling rough idle. Seems to lack power to me but im not sure. If i take the truck for a short drive when i come back and go to instantly restart it has no fire from injectors....hit it with a little ether and shes up and running again. Im fairly positive i have that narrowed down to a weak oil pressure sensor.(changing it tomorrow). The truck runs pig rich and never seems to go into Open loop.(i think heated 02 will change that).  I AM OPEN TO ALL SUGGESTIONS.. out of ideas myself.

I have a ALDL cable with WinALDL & Tuner pro rt but quite frankly do not know what i am looking forrolleye.gif I have attached a copy of my logs at a idle.

Parts replaced less than 300 miles ago.( All new with AC Delco parts)

Completely Rebuilt TBI unit with 2 inch spacer

New TPS & IAC i did my best to calibrate them

New map sensor

Pickup Coil ( Timed at 4 degrees BTDC with connector unplugged) 

Cap rotor & Plugs & Wires


Ignition coil

o2 sensor ( Re wired from ecu wire was broke assuming when they reinstalled the engine)
*** I plan on switching to a heated o2 due to my long tubes.


Knock sensor (Wire was also broken)

Newer fuel pump & Filter 15k ago with all new lines 

Im sure there is plenty others im forgetting. The EGR is deleted as are all other vac lines except MAP,PCV. I am at my wits edge with this truck but i love it very dearly. Hopefully the geniuses on here can help me figure it out. At this point any direction is better than none.

Thank you very much you can email me at [email protected] Or text me at 724-570-8672 if that is easier.


Picture of said truck causing me all this heartachemad.gif


Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...

Important Information

By using this site, you agree to our Terms of Use.