my 2004 4.3 engine is constantly overheating

Asked by Jul 30, 2016 at 10:56 AM about the 2004 Chevrolet S-10 4 Dr LS 4WD Crew Cab SB

Question type: Maintenance & Repair

When the truck idols, its fine. when driving the temp needle goes above
210. heat comes down to the floor board that almost scalds your feet
through your shoes. if i turn on the AC temp really shoots up while driving.
Fan is strong, replaced coolant sensor, thermostat, flushed radiator system
of red rust, and checked for leaks. I know the pump is working becouse
when i crank it with the cap off it sucks the coolant on down. cleaned out
around the grill and radiator. evn checked to make sure the oil and coolant
were not mixing. what else is thier to do? im lost!!

3 Answers

25,195

Try checking your water pump again, squeeze the upper radiator hose when revving the engine, you should feel the pressure build. It may have lost some efficiency from wear. Another test is for hydrocarbons, a product like Napa's "Block Tester" will let you know if combustion gases are causing coolant to overheat. Not all head gasket leaks result in oil/coolant mixing. If you have hydrocarbons present you have a head gasket issue.

1 of 1 people found this helpful.

and what would be an easy way to check and make sure the radiator is cooling and not leaking internally? any ideas?

25,195

It wouldn't leak internally but it may be clogged up with hard deposits with a loss of efficiency. You might still have enough "flow" to get by with a typical garden-hose flush but not good enough to prevent overheating. Also make sure after any work you get all the trapped air out of the system.

1 of 1 people found this helpful.

Your Answer

Add photo

Related Questions

  • my 2004 4.3 engine is constantly overheating 3 answers

    When the truck idols, its fine. when driving the temp needle goes above 210. heat comes down to the floor board that almost scalds your feet through your shoes. if i turn on the AC temp really shoot...

    2004 Chevrolet S-10 4 Dr LS 4WD Crew Cab SB

    -

    Maintenance & Repair

  • 1994 Chevy S10 4X4 4.3 TBI engine. 1 answer

    A while back the engine would gradually slow down and die. Will not idle. I have replaced the map sensor, taken egr valve off and cleaned, new temperature switch, different throttle body, new fuel p...

    1994 Chevrolet S-10 2 Dr LS 4WD Standard Cab LB

    -

    Maintenance & Repair

  • 2002 Chevy S-10 4.3 v6 that has the code of cyl 4 misfire but there is no misfire. 4 answers

    on my 02 Chevy S-10 4.3 v6 that has the code of cylinder 4 misfire but there is no misfire, the truck runs and idles perfect, I have to get the thing smog tested and it will not pass because check eng...

    2002 Chevrolet S-10

    -

    Maintenance & Repair

  • is there a big difference in a 92 and 93 4.3 ecm 1 answer

    howdy just swapped a 93 4.3 for a 92 4.3 the ecm has different plug ins and i'm getting a code for the tc sensor so its loading up and idling rough other than that runs good

    1993 Chevrolet S-10 2 Dr Tahoe 4WD Standard Cab SB

    -

    Maintenance & Repair

  • 98 4.3 engine won't start when cranking but almost starts when key is turned back to on 3 answers

    plugs spark, I can hear fuel pump,I've replaced the fuel filter,ignition module and the crankshaft sensor.I've tried starting fluid and gas and the only time it sounds like it's trying to start is whe...

    Chevrolet S-10

    -

    Maintenance & Repair

S-10

Looking for a Used S-10 in your area?

CarGurus has 1,329 nationwide S-10 listings starting at $1,999.

ZIP:

Search Chevrolet S-10 Questions

Chevrolet S-10 Experts

#1 Andrew Olsen
Andrew Olsen
Reputation 2,360
#2 John Saffrahn
John Saffrahn
Reputation 1,000
#3 Trebor66
Trebor66
Reputation 990
View All

Related Models For Sale

Used Ford Ranger
171 Great Deals out of 5,557 listings starting at $900
Used Chevrolet Silverado 1500
1,898 Great Deals out of 182,420 listings starting at $1,595
Used Chevrolet Colorado
245 Great Deals out of 27,383 listings starting at $1,000
Used GMC Sonoma
6 Great Deals out of 430 listings starting at $1,488
Used Toyota Tacoma
547 Great Deals out of 42,550 listings starting at $1,995
Used Ford F-150
2,115 Great Deals out of 192,318 listings starting at $290
Used Dodge Dakota
128 Great Deals out of 3,787 listings starting at $1,500
Used Nissan Frontier
338 Great Deals out of 20,768 listings starting at $1,250
Used Chevrolet Blazer
1,180 listings starting at $1,495
Used GMC Sierra 1500
769 Great Deals out of 68,174 listings starting at $1,700
Used Dodge Ram 1500
402 Great Deals out of 10,915 listings starting at $1,000
Used GMC Canyon
96 Great Deals out of 11,929 listings starting at $3,500
Used Toyota Tundra
418 Great Deals out of 34,386 listings starting at $2,500

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.