Intake Spacer Failure

[Iron-Mike]

I bought the 1" intake spacer for my 2000 limited explorer and had it installed. Gaskets were replaced and the right length bolts were used.

I got in the truck and started it up and the idle was all over the place from almost stalling out to idling as high as 1500rpm. Engine was checked for manifold leaks which it had none, throttle cable was adjusted (didn't help). After leaving the truck with the shop for 2 weeks and them not able to find the problem I had them remove the spacer and go back to stock. Engine ran just fine once the spacer was taken out and everything that was adjusted due to the spacer install was brought back to normal settings.

So in all 2.5 weeks of time wasted and I was out $400 in labor and parts and have nothing to show for it.

Anybody have a clue as to what would cause this?

 

[chriswells78]

was it the type of space you put between the upper and lower manifold or the type that goes between the throttle body and the upper manifold?

 

[Iron-Mike]

it was the spacer for the upper and lower intake manifold. I heard the throttle body spacers were crap and a waste of money so I never invested in one.

 

[Nocturnall]

Did they try resetting the computer and running it? If it's going to make a decent change to the performance of the engine resetting the computer so it can relearn the idle and all that with the changes is a good idea. Otherwise your x is just sitting there thinking something's screwed up.

 

[Iron-Mike]

as far as i know they didn't. They just installed it and tried letting it idle for awhile to let the computer do the learning but I seriously doubt they reset it or anything. They didn't even bother to disconnect the battery during the install cuz I didn't lose any of my settings on my aftermarket radio. So they must have just installed it and turned the key.

 

[Nocturnall]

It won't just relearn. It will try and run, but it won't just relearn the idle unless you d/c the battery, let it sit for a min or two then reconnect. It was trying to run like it does without the spacer which just wasn't workin.

 

[Iron-Mike]

the mechanic told me that the drastic change in the system is throwing off the vacuum in the system or something and that was why it was idling rough and lopey. On top of it all the brakes were messed up because of it as well. You had to REALLY mash down on them to get it to stop when you wanted to. Which I was told was also because of the brake booster not getting enough vacuum or something to that effect.

I'm willing to try it again if someone local to me is willing to have a go at it that knows what they're doing.
I'm in Boston, MA...

 

[410Fortune]

the instake spacer will not effect manifold vacuum unless something is wrong during the installation. High ide = vacuum leak
Lack of power brakes = vacuum leak

Sounds to me like your mechanic messed something up, either a gasket, or a vacuum port/hose was not installed properly.

Any time you clean./change or modify a sensor, or change the airflow, intake spacer, throttle body size, etc etc the computer MUST be re-set to allow it to re learn the new readings it will be getting from the sensors.

A simple 1" intake spacer should not have had any effect on your idle, unless it was not installed properly.

Can you tell me how they checked your intake for leaks after installation?

The GT-40 intake on the explorer is a bit of a chore to remove and re-install, it takes me 2-3 hours to do the whole job and I have taken them apart a few times. The bracket for the coil packs must be modifed to accomodate the spacer. There is no adjustment for the throttle cable unless you are referring to removing any slack. The idle set screw on the TB does not need to be adjusted when installing a spacer.

My best guess is your mechanic got lazy and blamed a faulty installation on your aftermarket part, which he/they apparently do not understand or are not familiar with.

hope that helps.

 

[Iron-Mike]

That about sums it up in a nutshell! He tried to adjust the idle set screw to compensate for the lopey idle. I had to put the set screw back to where it was when they took the spacer back out. I think I'm going to wait until I get my TM headers before I have the intake spacer put back in. I gave them everything they would have possibly needed for that install. New gaskets, the longer bolts, the intake spacer kit still in the packaging unopened.

When I'm ready to have it done I think I will try and find someone on the forum here that is close enough for me to drive to and have it done. Apparently the guys I took it to have no idea what they're doing when it comes to simple procedures like an intake spacer. They even broke the EGR tube during the install and I had to buy a new one at $105.00 from the dealer to top it all off..

Thanks for all the input guys I seriously appreciate the info. I know what to do the next time I'm ready to have a go at it

 

[baseballX]

If they broke the EGR tube they should pay for it, sounds like a horses*** shop to me.

 

[dogfriend]

What is the theory behind adding an intake spacer? What is it supposed to do? I am serious, I don't get how they are supposed to work. Do they actually help?

I have seen the throttle body spacers that are sold in Summit, etc. for the 4.0 engine but I can't see how they actually do anything at all.

 

[410Fortune]

????????????????????????????????????????

They break the EGR tube and you pay for a new one, did you ask for the broken one back? I could tell you all day long you needed new parts, charge you for them and you would never know the difference.

 

[Dan Whitaker]

The broken EGR tube would cause the problem with the idle.

The EGR tube has to be extended to reach the EGR valve. The asshats must have broke it trying to figure out to extend it.

 

[Dan Whitaker]

What is the theory behind adding an intake spacer? What is it supposed to do? I am serious, I don't get how they are supposed to work. Do they actually help?

I have seen the throttle body spacers that are sold in Summit, etc. for the 4.0 engine but I can't see how they actually do anything at all.

By moving the upper part of the intake up it allows for cooler fuel atomization because there is a lot of heat that builds up in the lower intake causing the fuel to vaporize.

You will gain torque this way which we desperately need.

 

[Iron-Mike]

My plan at this point is to hold off on installing it until I get the TM headers so I can have the EGR tube modification done to the headers first so there is no stretching of the EGR tube on installation and things should hopefully work out better the next time around.

Just to give you guys a heads up the new EGR tubes being sold at the dealership do NOT have the accordian looking section in the middle anymore. They are a single unit pre-bent to shape and are not stretchable!!!

 

[410Fortune]

ouch that sucks

the TM headers come with a nice fitting that will lift your OEM EGR tube up about 3/4" allowing it to fit better with the spacer

 

[dogfriend]

By moving the upper part of the intake up it allows for cooler fuel atomization because there is a lot of heat that builds up in the lower intake causing the fuel to vaporize.

You will gain torque this way which we desperately need.

Ok, thanks for the explanation. So this is a mod for the 5.0 only.

I still don't think that the throttle body spacers do anything, unless someone has data to show otherwise.

 

[410Fortune]

I had a spacer made for my old 2.9L, a simple piece of 3/4" thick phenolic cut on a band saw to match the gaskets

You can make a spacer for the Ford 4.0L OHV, at least the 91-94 with the metal intake. The SOHC and 95+ 4.0L are harder/impossible because of the o ring sealed plastic intakes....nobody I know of has done it ....yet

 

[dogfriend]

I had a spacer made for my old 2.9L, a simple piece of 3/4" thick phenolic cut on a band saw to match the gaskets

You can make a spacer for the Ford 4.0L OHV, at least the 91-94 with the metal intake. The SOHC and 95+ 4.0L are harder/impossible because of the o ring sealed plastic intakes....nobody I know of has done it ....yet

Yeah, but if I get more torque, I will probably kill the tranny, LOL.

I may have to pull the intake manifold soon, because I'm getting signs that I have an intake gasket leak. If I do, I'll take a look to see if it may be possible on my 97 4.0 OHV.

Then again, with the plastic manifold, maybe this isn't an effective mod anyway. Ford already sort of did it?

 

[410Fortune]

exactly the heat soak issue and the cost of aluminum is why I suspect we see plastic manifolds these days

but the spacer does increase the intake plenum runner length = toque