'01 Yukon Throttle body cleaned, low idle & quits now

[bill9000]

Hi, trying to nurse this old 01 Yukon (5.3) I have through the winter... (has 142,000 miles) not going so well.

I had cleaned the throttle body, it was BADDDDD. Then it was randomly dipping idle at stops and sounding like a little miss. (I also put new plugs & wires)

So today, I went and replaced the Throttle Position sensor and the Idle Air Control valve. Both brand new in an attempt to fix the idle.

It was unsuccessful, there was no change, if anything it is worse, because now when you start it... it immediately idles all the way down and quits. the only way to keep it going is to hold the throttle up a little.

It runs fine, does NOT idle high like everyone talks about, it idles real low and tries to quit at red lights...

I tried the run for 3 mins at idle, like was suggested on YouTube, shut off for min, then repeat... that did not work.

Is there anything else I can do??? it's supposed to snow the next two weeks straight and I'm screwed if I can't fix this thing!

** there is NO code, no CEL, and nothing else wrong except for rough and low idle)
Thanks in advance for any help!

 

[Doubeleive]

the replacement iac needs to match the old one exactly, if you give your dealer parts department the last 8 of your vin they can match it up or look in the local junkyard for a matching one

 

[bill9000]

the replacement iac needs to match the old one exactly, if you give your dealer parts department the last 8 of your vin they can match it up or look in the local junkyard for a matching one

can you8 elaborate on what you mean? I compared the new one and it was EXACTLY the same in all aspects. (visually)

 

[Doubeleive]

can you8 elaborate on what you mean? I compared the new one and it was EXACTLY the same in all aspects. (visually)

did you buy a oem one? if not then they wont match, the iac nipple is probably sitting lower which is why it dies at idle, pull it out and measure it compared to the old one.
that's a very sensitive part if it's a really close match the dealer may be able to adjust it but there going to probably charge $120 to do it and if they can't then you'll end up having to get another one anyway, it's kind of a gamble.
this is just my opinion from previous experience I ended up just grabbing a clean looking one from the junkyard and it worked out fine

 

[bill9000]

did you buy a oem one? if not then they wont match, the iac nipple is probably sitting lower which is why it dies at idle, pull it out and measure it compared to the old one.
that's a very sensitive part if it's a really close match the dealer may be able to adjust it but there going to probably charge $120 to do it and if they can't then you'll end up having to get another one anyway, it's kind of a gamble.
this is just my opinion from previous experience I ended up just grabbing a clean looking one from the junkyard and it worked out fine

it's not oem, but it looked identical.
I suppose I could try cleaning it and putting the old one back in if that's what's causing the problem.

I try to avoid the dealer at absolute all costs, they can't even seem to do an oil change right without messing things up. I've seen nothing but them trying to screw people.

I'll pull it out and compare that length! I appreciate the help! (can I clean the old one with something and not be hurting it?)

 

[Doubeleive]

it's not oem, but it looked identical.
I suppose I could try cleaning it and putting the old one back in if that's what's causing the problem.

I try to avoid the dealer at absolute all costs, they can't even seem to do an oil change right without messing things up. I've seen nothing but them trying to screw people.

I'll pull it out and compare that length! I appreciate the help! (can I clean the old one with something and not be hurting it?)

if it was idling ok before then yes you can maybe get away with just cleaning it up, I would also clean inside the hole where it goes in, there is usually a bunch of carbon inside there as well I used to just use a soft cloth with some cleaner sprayed on it and stick it in there spin it around you might be surprised how much carbon is in there takes a few times to get it all

 

[bill9000]

if it was idling ok before then yes you can maybe get away with just cleaning it up, I would also clean inside the hole where it goes in, there is usually a bunch of carbon inside there as well I used to just use a soft cloth with some cleaner sprayed on it and stick it in there spin it around you might be surprised how much carbon is in there takes a few times to get it all

ok, no it wasn't idling ok before, it was sputtering in gear at red lights and idle dipping real low before, that's why I cleaned the TB, chanced these things... was trying to fix that specific problem.
OK I can clean in there. it's gonna be a little tough now cause it's already started snowing and cold, but I should be able to get it done.

 

[Doubeleive]

ok, no it wasn't idling ok before, it was sputtering in gear at red lights and idle dipping real low before, that's why I cleaned the TB, chanced these things... was trying to fix that specific problem.
OK I can clean in there. it's gonna be a little tough now cause it's already started snowing and cold, but I should be able to get it done.

well it certainly wont hurt to try, if it doesn't your best bet may be to try and find a used oem one if there is any junkyards around there just take the old one with you match it up

 

[bill9000]

well it certainly wont hurt to try, if it doesn't your best bet may be to try and find a used oem one if there is any junkyards around there just take the old one with you match it up

since the problem was a crappy low idle before, is it possible the Throttle Position sensor was to blame, and I fixed that by replacing it, but caused a new problem with the new IAC?

 

[Doubeleive]

since the problem was a crappy low idle before, is it possible the Throttle Position sensor was to blame, and I fixed that by replacing it, but caused a new problem with the new IAC?

well the those stupid iac are apparently all slightly different even at the junkyard there is like 3 different ones from similar years, if you look online there is like 150 different models that all LOOK like they would fit and work but there different. I would bet it's just the iac not matching up to the old one