Engine Throttle sticking

[Magnet86]

Hello, all:
The other day I took the 86GT for a ride; don't get to do that much with cold temps and my work schedule. The throttle stuck in part load and I had to get heavy on the brake, then drop the clutch and quickly shut off the engine. Drifted to the side of the road safely and popped the hood and yep- the throttle was stuck open somewhat. Slight pressure and it snapped back to idle position. Drove it home with no probs. The throttle cable was finally replaced about three years ago and this is the first trouble I've had. The factory cable became loose on the little ball stud and came off on me a while back. Is this a cable lube prob or does the throttle lever/ cable attach point need attention? I know I should clean the throttle body as well but it hardly gets used these days. But I can clean it, no prob there. Cable routing is exactly like the factory set-up. My car has dealer added cruise, but I don't use it much except on the highway. Its installed factory as well. Thanks much.

 

[AeroCoupe]

First thing I would do is pull the inlet tube off the TB and make sure that is not varnished up. Once you have done that then post back up.

 

[Magnet86]

Finally got around to the car since the weather improved a bit. Removed the throttle body and cleaned it thoroughly. New gasket. Also checked the bypass valve. All good and clean. Reassembled the throttle and discovered the throttle cable return spring will not return the throttle to idle, whether it is attached or disconnected. Worked it a few times by hand but still clearly sticking. Since the spring is accessible, is it possible to swap with the old cable? I still have it. The spring doesn't appear to be bent or stuck, it just doesn't do its job.

 

[Magnet86]

Here are two photos of the cable. It almost appears to be two springs; plus the insert seems to be the reason for the sticking. There's lots of motion when I work the throttle by hand. Plus its worse when connected to the throttle bracket.

 

[AeroCoupe]

I’m pretty sure the throttle body should snap back closed without the cable attached. If it’s not doing that then you need to replace it.

Also, that does not appear to be an OEM throttle cable so I would suspect it to be contributing to the problem.

 

[Magnet86]

Its not an OEM cable. Can't find one. When I had the throttle body off the car it closes easily on its own. There is actually a decent amount of tension in the throttle return spring. It appears the cable is binding but I'll check again and if needed, I'll put the old one back on. The connection to the throttle body was weak and that's why I replaced it. But maybe I can get it to stay on better. Definitely prefer factory items.

 

[AeroCoupe]

You can find them like this one:

87-93 Mustang 5.0 Throttle Cable V8 1987-1993 OEM | eBay

IN GOOD WORKING USED ORDER.

www.ebay.com

Or you can build one like I did:

https://www.corral.net/threads/1993-5-0-injected-throttle-cable-replacement-with-lokar-cable-this-is-a-long-post-with-lots-of-pictures.2514984/#post-18731903

 

[Magnet86]

I did manage to see a few used cables but wonder what condition they might be in. I dug out my old one and there are two photos of it below. The only problem is the attachment point- a little rusty and somewhat loose. Definitely think I need to change the cable. Maybe it can be repaired. Seems to work well.

 

[Magnet86]

Replaced the throttle cable with the original. Works much better but the attachment point under the throttle is loose. Likely will fall off on me while driving. Is there a way to make it tighter without really altering the set-up? I'm thinking fine wire or maybe I can squeeze the 'grip' part of the connector. Don't want to damage it.

 

[nickyb]

Thin wire sounds like it'll work,or a cap over the ball side before you snap the cable on?

 

[fasterthangas]

Squeeze it with pliers. I've done it several times. It doesn't take much.

 

[Magnet86]

All good ideas, thanks much. Ran into another problem. Seems the gasket is leaking slightly. It might be the wrong one. I ordered a few factory NOS gaskets but they don't seem right. Does anyone know the correct Ford part number for the throttle body to EGR spacer gasket? The shop manual lists part # 9E933 but I've seen a few prefixes and now have two that I can't use- one is slightly bent and the other is in numerous pieces. One prefix is E6SE, the other is E6ZZ. Knowing Z is the code for the Mustang, I'd guess that's the one I need but right now I can't find one. Not sure if the T-bird had the HO 302 or not, I would think both shared the same throttle body and the same gasket for 1986 but not sure. Not a T-bird guy. I'll keep looking. Thanks all.

 

[AeroCoupe]

You should be able to pick up FelPro gaskets at any parts store that will do the job nicely unless you are just wanting OEM gaskets. 83-88 T-Birds did not get the HO motors.

 

[Magnet86]

I just went with the Fel-pro gasket. Worked fine. I found a NOS throttle cable. It arrived the other week and since today's weather here was decent and I am off work, I had at it. 90 minutes and the new cable is on and looks great. Much better quality. My concern is the throttle body itself. I removed it and cleaned it again and the pitting and wear on the mounting surface really stands out. I used my Dremel tool and a fine wire brush to clean up the surface and it did look better. Maybe machining the thing someday will help? So with the new gasket I applied a small amount of thermostat housing sealant. Since that is what it is sealing against I thought it should do alright. I'd prefer to install the gasket dry but doen't want any leaks. All back together, I just haven't started it up yet. Probably should but time for a short break. Thanks all.

 

[AeroCoupe]

Should be just fine. You can take spray glue some wet-dry sandpaper to a known flat surface (thick piece of glass will do) and get the surface flat and pit free pretty quick. Work it with some 300 grit then move to 600 and finish with some 1000. Be liberal with the water.

 

[Magnet86]

Great idea. Will have to look into that. I let the car sit for a day and then fired it up. No coolant leaks and the engine ran fine, even idled good. I may need a battery however, due to lack of use but the car runs great. New throttle cable is very easy on the foot, I'll have to get used to it but works perfectly. Money well spent. Cheers.

 

[General karthief]

And another satisfied customer.
Don't for get to leave a 5 star rating........
Now go find something else to fix