Tbi 350

Asked by Feb 18, 2017 at 07:47 PM about the Chevrolet C/K 2500

Question type: Maintenance & Repair

I was given a 1990 chevrolet cheyenne. 2500 and
finally got it home. It had sat for about 6or 8 years.
I put a battery in it, new fuel pump and filter and
primed the throttle body and it started right up, it
idled well considering the circumstances. I was
able to drive it across the subdivision and back,
about 4 miles with no problem. And again the next
day just a block and back. On the second, short trip
it began to be difficult to keep running when in
gear. (it's A/T btw)  gradually but quickly it got
worse. Now it would not run unless I was
constantly and gently pumping the throttle. I have
cleaned the throttle body, tested the iac and tps
with a multimeter, adjusted ignition timing, and
looked for vacuum leaks with starting fluid. After
the timing adjustment I was able to get it to idle
but it was mildly to moderately rough. I thought I
was on my way but when I put it in gear it begins to
sputter and backfire. I can't even get it 30 feet
before it dies. It does not jump forward forcefully
or jerk it just idles down and then spits and
shutters till it dies. It will start right back up but
usually afterwards it USUALLY will not idle. It
seems there is little difference in the engine temp.
I'd like to get some some ideas for troubleshooting
but I have very basic tools and no access to most
tools needed for testing (i.e. Vacuum pump,
pressure guages, etc.) any and all useful
information will be greatly appreciated.  

1990 cheyenne 2500 5.7l tbi 2wd service bed

1 Answer

73,905

Well to start, possible fuel regulator in the TBI. Some how plug the return line from the TBI. Maybe find a rubber section of hose thats on the return line and pinch that. Start it up and see how it runs. Blocking this line would increase the fuel pressure indicating the regulator needs to be rebuilt.

4 of 4 people found this helpful.

Your Answer

Chevrolet C/K 2500 Experts

  • #1
    Rowefast
    Reputation
    290
  • #2
    COMETGUY61
    Reputation
    190
  • #3
    Andrew Olsen
    Reputation
    140
View All

Related Models For Sale

Used Chevrolet Silverado 2500HD
8 Great Deals out of 812 listings starting at $3,995
Used GMC Sierra 2500HD
18 Great Deals out of 856 listings starting at $3,995
Used Dodge Ram 2500
10 Great Deals out of 92 listings starting at $1,995
Used Chevrolet Silverado 1500
182 Great Deals out of 11,059 listings starting at $1,995
Used Ford F-250 Super Duty
21 Great Deals out of 921 listings starting at $6,800
Used GMC Sierra 2500
7 listings starting at $9,995
Used Chevrolet Silverado Classic 2500HD
7 listings starting at $11,988
Used Ford F-250
7 listings
Used Chevrolet Silverado 1500HD
3 listings starting at $9,995
Used Ford F-150
493 Great Deals out of 10,170 listings starting at $3,450
Used Chevrolet Silverado 3500HD
5 Great Deals out of 279 listings starting at $15,840
Used Ram 2500
13 Great Deals out of 1,462 listings starting at $10,995

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.