1987 Chevrolet 350 tbi high idle

[iamtherealJayy]

The cap is still there never been tampered with. The butterflies appear to be completely flat and closed. So you recommend ordering an iac instead of purchasing one from oreillys/autozone? I’m fine with the wait, just curious on your reasoning. Brand specific? Price difference? Quality?

 

[gmbellew]

The cap is still there never been tampered with. The butterflies appear to be completely flat and closed. So you recommend ordering an iac instead of purchasing one from oreillys/autozone? I’m fine with the wait, just curious on your reasoning. Brand specific? Price difference? Quality?

I used a parts house random IAC last year because i had high idle issues. It worked for a while. but I had to replace it again because of high idle a couple months ago. I replaced it with a Delphi this time, which I figure is as close to OEM as I can get. so far so good. I am getting picky about trying to get the best parts I can lately....

 

[iamtherealJayy]

Agreed. If I can wait on shipping I usually do but if I need to get it done ASAP I go to oreillys. Also, can I use say a microfiber towel to help clean inside the throttle body hole for the iac? Or should I use only carb cleaner? I don’t want to spray too much carb cleaner into it so it leaks into the intake

 

[iamtherealJayy]

Since I broke the clip on the connector :facepalm: is there a way to repin a connector? Or would I have to cut the wires and redo it all?

 

[gmbellew]

Since I broke the clip on the connector :facepalm: is there a way to repin a connector? Or would I have to cut the wires and redo it all?

I don't think you have to worry about the connector coming off just because the retainer clip is broken. I'd wrap it in a little electrical tape if you are worried.

 

[gmbellew]

Agreed. If I can wait on shipping I usually do but if I need to get it done ASAP I go to oreillys. Also, can I use say a microfiber towel to help clean inside the throttle body hole for the iac? Or should I use only carb cleaner? I don’t want to spray too much carb cleaner into it so it leaks into the intake

see if you can get eyes or your cell camera in there to see how it looks and clean appropriately.

 

[iamtherealJayy]

Alright that’s good atleast, I didn’t think it would necessarily come loose it was still pretty tight with the rubber seal, just rather be safe than sorry.

 

[iamtherealJayy]

It’s way past dark now (8:36pm been dark roughly four hours) I will take the iac back out tomorrow (pain with the egr and map sensor in the way) and get my phone camera down in there and observe the hole and clean it. If you’re familiar with throttle bodies is the tube coming from the back of the drivers side valve cover going to the back of the top of throttle body removable? I’ll clean all the removable parts of the throttle body if I can. It’s a metal tube (pcv I assume?) I know it’s removable from the valve cover, wondering if can be removed from throttle body?

 

[gmbellew]

everything should be able to come off the TB.

you could get an IAC from oreillys if you can't wait. just be cautious that it MAY need to be replaced sooner than later. but it could also be fine for years....never know

 

[iamtherealJayy]

Oreillys: $45.99 for a masterpro… parts geek: $50.58 for a Delphi, I can wait a few days debating on just taking it out and cleaning thoroughly again and waiting on the aldl or just going ahead and ordering a new one, atleast if it’s new I’ve got one less thing to assume is the problem.

 

[Rusty Nail]

I don't think you have to worry about the connector coming off just because the retainer clip is broken. I'd wrap it in a little electrical tape if you are worried.

*Or rubber cement works great and you can't use too much.

No distributor pix but its no matter. Bound to be an ignition timing ?

Try a 14mm or 9/16 combination wrench to loosen the distributor hold down bolt ever so slightly.
Best thing you can do tomorrow is find the tan wire with the black stripe coming out of the firewall about 11 o'clock and unplug that connector - let it hang and turn the truck on.
Now that you have the distributor hold down bolt loose, turn the distributor to the LEFT, or COUNTERCLOCKWISE ever so slightly - to bring the idle speed down - ever so slightly - see if you can find the right spot to turn it to having sat in gear holding the brake.

See if you cannot force a change THAT way. Gotta pull distributor to install engine, now ive gone from cracked head (it still is though) to advanced ignition timing.
The fan is still too far into the shroud AND that water pump is WAY past too old to be playing in the big leagues of the GMSB.
Looks OE to ME. You simply must replace it too.
But the good news is that you can use water now until u get it fixed, you dont gotta spend anymore coolant.

 

[iamtherealJayy]

@Rusty Nail The timing is 8° btdc when the truck is warm, I thought about retarding it but I couldn’t wrap my brain around which way to turn it. May I ask what that tan wire is? Why must it be unplugged? Also the truck is a manual, I can’t sit in gear and hold the brake unless I slip the clutch to make it bog. I don’t know how to adjust the fan in closer but I can measure today and tell you exactly how far in the shroud it is. Will also get pictures of distributor and wiring.

 

[Rusty Nail]

The tan wire takes the place of a vacuum canister for these purposes..youve got to unplug it to remove the computer's control.
Does the truck have an OE catalytic convertor on it still? A plugged up cat would sure as hell make it run hot....tell us it's still there.

A really, really, REALLY good question is - how do you know the timing advance is at 8° but you dont know what the tan wire is?

Hmmm?

So youve set the timing without unplugging it or? That shure as hell could cause your problems.

I feel like this is a good tree to bark at, this must be the say we finally woke up on the right side of the bed!

 

[iamtherealJayy]

It’s had an exhaust done, I’ll go check if it’s got the cats. And long story I had some wheels(the ones for the k10 bonanza) and needed the center bore milled so took them to a machine shop and the guy insisted on checking the timing on my truck since I mentioned it idled high when he kept talking about the truck. I’ve never messed with the timing personally due to I’m very paranoid about making it worse :/ but hell gotta get worse b4 it gets better right?

 

[Rusty Nail]

Dude unplug that wire and turn it a little bit LEFT until it acts right, we're gettin ready to fix it.