2002 Chevrolet Tahoe died after new IAC

Car dies out right after start I put new idle air control valve and coil packs and wires and spark plugs and air filter oil change oil filter can’t find a loose hose

did you plug the connector back on the idle air control?

if you did retrace your steps to see if you missed something. you might have accidently removed a vacuum hose or wire.

Thank you for your respons I checked all connectors and tryed spraying carb cleaner on the hoses to try and find a vacume leak and can’t find one

did the new iac have a o-ring on it when you installed the sensor? if not you could have a vacuum leak there.

first try cleaning the throttle body and if you disconnected the battery you can try this…

GM throttle body relearn procedure — Ricks Free Auto Repair Advice Ricks Free Auto Repair Advice | Automotive Repair Tips and How-To

It didn’t have a gasket just a o ring

yes sorry I meant a o-ring.

Yes o ring is in I don’t have torque wrench so it’s not torque to the right tension but I did tighten it as tight as I could

were you having stalling problems before you did the work? will it stay running if you keep the rpms up?

has the fuel filter been changed?

Where Is the Fuel Filter on a 2002 Chevy Tahoe? (itstillruns.com)

No it sounded like it wanted to die but never did and yes if I hold the gas a little it stays running

That’s the next thing I was going to try

did you have a check engine light on before you did the work? if you did can you post the codes.

also, if you dont have a scanner, autozone and a lot of auto part stores have a loan a tool program. you would give a deposit of what the tool would cost new and you would get it back when you return it.

If the engine doesn’t stall if the gas is slightly pressed, then it sounds like you got a bad IAC valve.


Might be the iac passages are clogged with carbon. Cleaning the throttle body like you mentioned would be a good idea. If that or another iac valve doesn’t work…post back and we’ll regroup.

Suppose it could be a maf sensor issue, or fuel supply issue.

I like the changing to fuel filter idea. Needs to be done periodically anyway.

Maybe you need to go back over the engine closely to see if there is a vacuum line disconnected or cracked. At 19 years old that is not unheard of and with a manifold vacuum leak an engine will not idle or idle roughly if it does.

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I thought it was a bad Arc valve also so I got a new one put in that didn’t help it at all I did clean out the throttle body that didn’t help it at all either well I did and I didn’t have a day off I have a scanner at home just the one gets from Walmart I’ll after work I’ll see if it gives me code

Good ideas above, that’s where to start. If none of them pans out, other possibilities :

  • battery/charging system/ground connection problem
  • faulty crank position sensor
  • serious vacuum leak (basic vacuum system check, and especially check pcv system and power brake booster).

I have 3 codes p0174 p0171 lean in both banks and p0102 valume air flow a circuit low