I posted this on my native durango forum, but like to get input here as the motors are the same.

So I had purchased the Hughes airgap awhile ago and finally got the chance to install it. About halfway through, I began regretting it and wishing I had left it stock. Not happy at all with the fit/finish and install process, but that is a story for another day.

The issue now is it idles erratically and dies when coming to a stop every time. It reminded me of when if you would try and come to a stop with a manual transmission without pushing in the clutch...the motor would try and compensate and stay running and the result was a bucking idle and eventually the motor dies. As I get closer to a stop, seems to get worse. /if i pop it into neutral, it smooths out. After it dies, it will start back up normal. If I let off the gas at say 35 mph and gradually slow down, (such as coming into town with a lower speed limit) it drops to an idle then fluctuates constantly by about 100 RPM. As I said, when I get closer to a complete stop, it gets much harsher and will die. it idles smooth otherwise and seems to run smooth down the road. It is showing codes for O2 sensors, p0132 0138 and 0141. These just showed up during the install process. I'm not sure if this is a possible culprit.

Couple other possibilities I have come up with:

Possible Leak around fuel injectors?
On of the three sensors on the TB, TPS, IAC, MAP?
One of the requirements of the new intake is relocating the IAT sensor.Another possibility?
Missing a vacuum hose on the intake?

Any insight?

Edit: I know a dying battery likes to cause electrical issues in these trucks, mine is new within the last few months.
I also have cleaned the IAC plunger recently, so if that is the cause then the sensor itself has gone bad somehow.

 

Where did you put the iac? Or whatever sensor you had to relocate.

 

Directions said to cut an "x" in the intake tube and stick it in there. The new intake did not have a port for it. Seems a little iffy, one of several reasons I was not happy with the quality of the product.

 

I imagine it has something to do with that

 

Some easier things to do towards determining root cause....

Revisit install instructions and slowly go through it with high fidelity.

I'd verify you have no vacuum leak b/t the intake and the block for starters.

Then trace down the vac lines.

Remove front O2 sensor, drive and any change?



wth is Spillage!?!?! lol

 

You didn't use the front and rear lifter valley gaskets did you? The intake will not seat with those in there because the intake was designed for the older LA blocks and hughes don't care to design one for our trucks.

IAC wouldn't cause your issue. I put mine in the side of the intake below the TB

 

The install instructions were rather poor, but I will give it a shot. There were four vacuum ports on the drivers side, and two on the passenger side with the manifold but I could only find/remember one vacuum line on each side to hook up, the rest had to be plugged. This didn't seem right. Directions did not specify. Beeker: Just noticed you have this intake (probably why you knew about the gaskets). How many vacuum hoses did you have hooked into the intake? do you by chance have a install thread I could try and compare against? I did not use those gaskets. Again very poor service from Hughes. Didn't even mention that I should not put them in, yet they came with the kit so I had to assume right? I eventually figured it out when the intake would not sit correctly.

For clarification, it was the IAT sensor that I moved. I think the IAC is bolted to the throttlebody. I forgot to mention that I replaced the throttlebody while I was in there as well. So all the sensors and linkage had to be moved over. I just can't imagine why the o2 sensors would go bad as a result of the install. I checked the codes then removed them, and they popped up again about five miles down the road. I will remove the front one and see what happens.

 

https://dodgeforum.com/forum/2nd-gen...ll-thread.html

There's my install thread for you. I also had some issues with my idle after the airgap install. What happened in my case was the manifold bolts had worked their way loose after several driving periods...these bolts are the kind that stretch and are known to come loose after first install, even if torqued properly. I believe the way to prevent this is to torque them on install, loosen them, and then re-torque them again in the same pattern. The directions don't mention this if I recall correctly.

Dont give up on the airgap. It really is a good product in my opinion despite Hughes' shortcomings in customer service. I have a serious hunch that you have a vacuum leak - possibly from the bolts being loose or missing a hose

 

I had no problems with my AirGap install.
Used FelPro gaskets.
Put the AIT sensor in the K&N tube directly above it's stock location (no cable extension needed)... I drilled a slightly undersized hole and threaded it in.
I put the Holley TB on at the same time, and changed to 4 post injectors.
I used all new sensors.

+1 on the fault finding tips above.

 

I think I was able to fix the problem. The crossover line between the fuel rails was leaking slightly because I was not able to get it on properly. I was able to get some replacment line seated on their correctly and it seemed to rectify the problem. I think it was sucking extra air in after the throttlebody had already determined the mixture so the motor didn't know what to do with it. I also doublechecked tightness on the throttlebody itself and throttlebody mounting plate to the intake. Nothing was really loose but who knows.

I have not noticed any power gains. I think the computer is still in the relearn process, but I was expected something initially. We will see what happens, I am going to put about 50 miles on it today.

CSDavies26, did you have an issue with the allen plug that threads in rights behind/next to the thermostat housing? It wasn't tapered like I was expecting so it just kept threading into the whole and never tightened. As a result, I had an antifreeze leak there that I had to deal with.

Also, I noticed in your thread the issue of the fuel rail mounting brackets came up. This was one of my biggest issues with the intake. A truly poor design if you ask me. The short bracket on both sides really wasn't usable as they intended as they just did not line up well enough to bolt them together. hopefully what I was able to do will keep them happy, time will tell. The longer angled bracket worked well, not sure why they did not modify the other ones. My theory is that since Edelbrock actually manufactures the intake, Hughes just wanted to do as little as possible to retrofit the little details to work for our trucks so they could send the intake out the door and reap the profits.