current issues

[the big blue bus]

lately when i start it up it idles high. its used to idle high sometomes and shift realy high in first to second. now when i start it up cold or not driving it for a little while it idles high still but not when i go to hit the gas it will stumble and hesitate. if i give it gas slowly it will go fine. once ive been driving for like 10 minutes its back to normal idle and no issues. im not sure where to start. thinking its the tps but also been reading of the iac and the cts could be bad too. any ideas?

 

[_Dylan_]

coolant temperature sensor is where I would look first

 

[AtomicHoe094]

any codes? yea the temp sensor if it fails tells the computer its like -40* outside and then your truck will throw a bunch of fuel at it to try and get it warm.

 

[electro]

My truck idled high consistently. 2000 Tahoe.

So I removed and cleaned the iac valve (idle air control).

Two small torx bolts and one electrical connector and gently pull it out.

Then I got a little crazy and pulled on the pintle. ***Warning, don't do that. It will break and you will have to replace it. acdelco $70.

Anyway, just pull it out gently and then get carb cleaner or similar product. Some guys suggest something better I think and then spray some on and take a tooth brush to it. Get it all cleaned up. The pintle on my 2000 tahoe was black from the parts dealer so don't clean it silver or anything. I guess you just wanna get it moving freely again.

When I replaced mine my truck went form 1100rpm to where it currently idles, 600rpm.

Whether this fixes problem or not, can't hurt to clean it up. Save some fuel while idling.

Thanks for reading, good luck.

 

[the big blue bus]

i was goign to try cleaning the iac first. its throwing no codes which is weird

come to think of it i dont think my cluster has the CEL bulb in it... starting it today that liht doesnt light up. ill see if theres a bulb today after work when i remove the abs bulb. going to check all of the sensors too and see if i can see which is bad. it did it thismorning again. hit the gas and bout stalled out. only a 5 min drive to school. normally after its warm its all good. thinking ill clean the iac first and see if that helps. once the idles normal all is back to how it should be

 

[electro]

Well heres hopin

Keep us updated.

 

[the big blue bus]

so i had no CEL in the cluster so i put that in. its doing fine since ive been driving it back from work. but il see if it throw the light in the morning. going to test the sensors tomorrow

---------- Post added at 08:07 PM ---------- Previous post was at 07:16 PM ----------

so i checked the tps and it has good ground and power didnt have time to check signal. took out iac and cleaned it. ill see tomorrow morning if its better. i tested the resistance of the cts and got 770ohms

 

[the big blue bus]

cleaned the iac and still no better. no CEL but still stalls almost if i hit the gas really hard when its cold. could it be the cts?

 

[electro]

I don't know what that is. Or tps.

What are these things?

 

[_Dylan_]

I would try and replace the coolant sensor. The sensor thinks the engine is freezing cold and its running way too rich.

I don't know what that is. Or tps.

What are these things?

cts: coolant temperature sensor
tps: throttle position sensor
iac: idle air control valve
cel: check engine light