IAC Debacle

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Nov 5, 2015 | 10:24 AM

Stephenms

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From: Sarasota Florida

IAC Debacle

I have a 1987 C4 and I just replaced my IAC with a BWD part from Advance Auto. I know I know I should only replace electrical with ACDelco, shame on me. But the IAC was free and free is good. Now I'm having startup and idle issues. Did the testing to find the IAC is the culprit, obviously. I was searching online for IAC kits since the dealership wants my left kidney and my right pinky toe for it, I came up with two part numbers for what seems to be the exact same IAC valve.

From Amazon, GM OE ACDelco replacement parts "division"
Part #s: 217-437 and 217-415. I was reading through the forums and everyone says to go with the 217-415 but that one is 80 bucks compared to the 437 which is 43. Money isn't an issue with this kind of thing I'm just curious, why give the exact same description with two different part numbers. Is one for the 90+ L98s and one for below? I'd assume I need the 217-437 since the dealer cross referenced the part number with my year and said its a fit. Any input?

Nov 5, 2015 | 11:22 AM

antfarmer2

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set it per the fms then

try disconnecting your neg battery for ten min then drive it for 30 or so miles and see if your puter will set it

Last edited by antfarmer2; Nov 5, 2015 at 11:23 AM.

Nov 5, 2015 | 12:40 PM

Stephenms

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From: Sarasota Florida

Quote:

Originally Posted by antfarmer2

set it per the fms then

try disconnecting your neg battery for ten min then drive it for 30 or so miles and see if your puter will set it

I have already reset the computer and driven 50+ miles, no change. A buddy of mine says the BWD brand of IACs are usually calibrated incorrectly. Is he right, who knows. I just want to know about these part numbers before I purchase the wrong IAC. I'm going to stop by the dealer to see if they can cut me some slack

At start up the car will have elongated crank times, then once it does start it shuts off immediately, then when I crank it again it's instant start with a serious of shakes and rattles and high RPM, 1200/1300. If I don't wait for it to reach a decent temp it'll miss like every storm trooper of the starwars series. Say I throw it into reverse at 120 degrees, it'll lunge into reverse, then lunge into drive and acceleration is pitter pattering, feels like you disconnected the TPS and tried driving it and it's just missing and bucking when you try to accelerate. Then once I hit about 170+ degrees it's gone. Idle is a nice smooth 600 to 700 at idle in drive and acceleration is smooth

Nov 5, 2015 | 12:49 PM

antfarmer2

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I would look a the water temp sensor for the puter make sure it has good clean connections and the air is burped out of the system. that temp sensor can do some strange things.

Nov 5, 2015 | 01:00 PM

Stephenms

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From: Sarasota Florida

Quote:

Originally Posted by antfarmer2

I would look a the water temp sensor for the puter make sure it has good clean connections and the air is burped out of the system. that temp sensor can do some strange things.

It's been checked, that was the first thing I went to. I replaced the IAC because I had a new one lying around and I was putting the top end back together from a new intake gaskets and injectors job. So technically that IAC was the only electrical piece that was changed. I'll disconnect it and see how she does.

Nov 5, 2015 | 04:29 PM

Stephenms

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Disconnecting the IAC before start-up seemed to fix my issue, it started up immediately and went to a steady idle around the 900-1000 range. But once it's been running for a minute the idle stays at a steady 1000. Once I plug the IAC back in it went to its normal 600 and drove fine. I'll try tomorrow morning when it's totally cooled down. I let it sit for 6 hours today and didn't have an issue so let's see what 10 hours does, before I spend the 70 bucks on a dealership IAC :|

Nov 5, 2015 | 04:54 PM

ccrvtt

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A buddy of mine says the BWD brand of IACs are usually calibrated incorrectly. Is he right, who knows.

Exactly.

I have sold BWD IACs for over 8 years now and the initial failure rate is negligible. If you even suspect yours is defective return it to the store with your receipt and ask for a full refund. Advance, Auto Zone, O'Reilly's, & generally any other retailer will take care of you if you're not satisfied.

Your dilemma is not an isolated one. Sometimes there are two different part #s that are listed to fit the same application, often with wildly divergent prices. Invariably the customer will pick the $43 part instead of the $86 part. I would, too, absent the necessary information to choose the correct part.

This forum or a qualified Corvette mechanic is your best source of information.

Nov 5, 2015 | 06:18 PM

Stephenms

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Quote:

Originally Posted by ccrvtt

Thank you for the confirmation on the BWD! It's not the first time I've had trouble with them.

On both part numbers I put my year (1987) and base model corvette, one said it would fit the other said it would not. So for the one that wouldn't fit I put a 1990 base trim and then it said it would fit. Just really weird why it would list two and them be the exact same part, technically. But then again I guess if you have two different #s and they're both being sold there is a difference. The dealership cut me a deal for 73 bucks shipped. I'll tackle that early tomorrow morning and get it ordered.