Express, Savana & G-Series Vans Offered in both a full size van, or a large box truck, the Express is the modern GM workhorse.

Chevrolet Express
Platform: GMT Van

calling motor heads - throttle body Q - '03 Express

Thread Tools
 
Search this Thread
 
Old August 16th, 2024, 1:12 PM
  #1  
CF Active Member
Thread Starter
 
tbb2's Avatar
 
Join Date: Feb 2011
Location: Arlington, VA
Posts: 180
Received 4 Likes on 3 Posts
Default calling motor heads - throttle body Q - '03 Express

I have '03 Express 3500 with a peculiar throttle body (TB).

The common TB has a 100mm air inlet and an integrated vacuum line connection at the top left behind the plate.
My TB has a 94mm air let and the vacuum line is mounted just behind the TB to the front of the intake manifold.




Would the location of the vacuum line connection be the difference in air inlet size?
Would it impact the IAC function? Or "if the IAC fits wear it?"

This is revolving around an idle issue and the IAC,
I have been trying to locate an IAC for my TB but what they are, is in a black hole.
There are plenty of IACs for the 100mm TB and couple odd named aftermarket parts for the 94mm.

Searching for the P# 20663 J1702L of the original IAC, a #17113598 comes up.
But all other reference to the #17113598 go back to the 100mm TB.
Old August 18th, 2024, 9:10 AM
  #2  
CF Junior Member
 
Derrick71's Avatar
 
Join Date: Jun 2022
Location: Pensacola FL
Posts: 57
Received 21 Likes on 15 Posts
Default

I don't know the answer to the question on the part numbers and the IAC valve.

It might be easier to just swap in the common 100mm throttle body with the IAC and be done with it.
Old August 19th, 2024, 11:13 AM
  #3  
CF Active Member
Thread Starter
 
tbb2's Avatar
 
Join Date: Feb 2011
Location: Arlington, VA
Posts: 180
Received 4 Likes on 3 Posts
Default

Originally Posted by Derrick71
....

It might be easier to just swap in the common 100mm throttle body with the IAC and be done with it.
Amen.
Wouldn't the 100mm throttle body have a different mounting pattern?
The people that make these things aren't big on providing dimensions.
Old August 19th, 2024, 9:08 PM
  #4  
CF Junior Member
 
Derrick71's Avatar
 
Join Date: Jun 2022
Location: Pensacola FL
Posts: 57
Received 21 Likes on 15 Posts
Default

I can't say for sure on this van but I would lean towards it having the same bolt pattern and harness plugs as long as it's from the same generation. My guess is that all or most of the truck engines in a generation share the same bolt pattern and plugs. This way they can use the same parts for as many applications as possible. I've swapped different size TBs on other vehicles with no problems. Even from different sized engines. This one is cable actuated which is good. Swapping drive by wire TBs is a little trickier since they might have to be programmed.

This would probably be a basic question in an LS forum.
Old August 19th, 2024, 9:14 PM
  #5  
CF Junior Member
 
Derrick71's Avatar
 
Join Date: Jun 2022
Location: Pensacola FL
Posts: 57
Received 21 Likes on 15 Posts
Default

Also, if you can look up the gaskets for the TBs they might be listed with a diagram measuring the distance between the bolt holes. Or you might find the gaskets are the same part #.
I bet the answer is out there in Google if you switch up your searches.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
wpatters1229
Express, Savana & G-Series Vans
8
May 9th, 2020 1:57 PM
Cy55
Silverado, Sierra & Fullsize Pick-ups
3
May 9th, 2012 8:09 PM
ousig2408
General Tech
5
April 25th, 2012 2:07 PM
DieHard
S-10 & Blazer
6
September 9th, 2010 8:10 PM
juniorv25
Impala
1
May 14th, 2007 9:12 AM



Quick Reply: calling motor heads - throttle body Q - '03 Express



All times are GMT -5. The time now is 4:20 AM.