1990 Chevrolet K2500 350 5.7 TBI / Runs rough after installation of new fuel injectors and throttle body rebuild kit

Asked by Jan 10, 2016 at 12:24 AM about the 1990 Chevrolet C/K 2500 Scottsdale Extended Cab 4WD

Question type: Maintenance & Repair

I have done a rebuild kit on my throttle body.  Tore down to nothing. cleaned
everything up with throttle body cleaner. Replaced the fuel pressure
diaphragm, new fuel injectors, along with gaskets. Put back together and
installed on manifold. Hooked everything back up. Before a full start up, half
cranked over to build fuel pressure back up. Go to do a full start up and truck
starts, then which dies seconds later. While it runs in those seconds it
fluctuates rpms and runs rough. Truck stays running while foot on the throttle,
but note still runs rough. Fuel does come out the injectors while running.
doesn't smell flooded. All replaced gaskets do not leak nor does the
diaphragm. Could it be possible i have to re-time the time that now its getting
the correct fuel pressure? What do i look into here i am lost?

New fuel pump, lines tps and iac

3 Answers


not enough info///is it fuel or elect/vac at this point??


Sounds like there is a vacuum leak. Spray carb or throttle body cleaner around areas where work was done if vehicle starts to run right vacuum leak is in that area.


Are you 100% sure you put the plug wires on in the right order? 18463572 is the firing order. Any time you remove the distributor you need to time it. And as stated check for vacuum leaks. Also try the paper clip method to pull codes. It might help see something and give an area to focus on.

Your Answer

C/K 2500

Looking for a Used C/K 2500 in your area?

CarGurus has 215 nationwide C/K 2500 listings starting at $3,500.


Chevrolet C/K 2500 Experts

  • #1
  • #2
  • #3
    Andrew Olsen
View All

Related Models For Sale

Used Chevrolet C/K 3500
180 listings starting at $4,000
Used Chevrolet C/K 1500
806 listings starting at $2,600
Used GMC Sierra 2500
169 listings starting at $4,995
Used Ford F-150
2,998 Great Deals out of 231,247 listings starting at $1,300
Used Ford F-250
425 listings starting at $2,500
Used GMC Sierra 1500
1,097 Great Deals out of 61,964 listings starting at $1,295

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.