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94 GM Suburban EGR valve removal

I have been getting an intermittent code 32 which is only stored after about twenty minutes of highway driving. The truck is used mostly for short trips under 15 miles and is not a daily driver. Once every four to six weeks it gets a sustained highway drive - two hours there with a four to six hour visiting interval where the truck cools completely and two hours back. The service engine light soon comes on after twenty minutes or so on the highway and then goes out after three to five minutes of continued operation. I am not experiencing any operational issues ie. pronounced poor idling or power loss and the stored code disappears after twenty or thirty starts in town so my guess is the valve is dirty and needs a good cleaning. My Chilton manual says to disconnect the battery, remove the air cleaner and then remove the single vacuum tube from the valve. Then remove the bolts/nuts and lift out the valve and gasket. Sounds so simple but…I can’t get anything but a crescent wrench on the nuts and even that takes a bunch of finagling. There’s no room to use any of my sockets. Also there’s a line coming off the base of the throttle body which seems to be a likely impediment to wrench ‘travel’ on the inside nut yet there is nothing in the manual about the necessity of removing it. Is there a special type of socket or wrench for this job (I’m thinking I need an extension to get sufficient leverage on my rather short 13mm crescent/closed wrench). I want to make absolutely sure I don’t strip the heads on these nuts. Any suggestions on tools or techniques would be greatly appreciated.

This project may be your excuse to get a new set of wrenches:

http://www.sears.com/craftsman-7-piece-universal-ratcheting-wrench-sets-standard/p-00921028000P?prdNo=8&blockNo=8&blockType=G8

Those^ sears are nice but I compared them at Sears side by side with the gearWrench* variety. The GearWrench ratchets within five degrees. The sears seemed to need more before it would ratchet. That will help you in tight quarters.
They also make a bent interference** wrench capable of ratcheting that has proven very handy.

*http://www.amazon.com/GearWrench-9700-Flex-Head-Combination-Ratcheting/dp/B0002NYD3K/ref=pd_cp_hi_1

** http://www.gearwrench.com/catalog/wrenches/ratcheting/half_moon_reversible/

Don’t be afraid to remove parts to gain better access to the valve. Just because a manual doesn’t say to remove a part to gain better access doesn’t mean you can’t. Sometimes partially removing something is sufficient. Just be sure you don’t remove anything that will create more problems than it solves.

As for tools, check some tool catalogs and see if there are any that will help you. You can check the websites for Snap-on, SK Tools or Sears, for example. You don’t have to buy those brands necessarily but they’re handy to see what’s available to help you. Sometimes you just have buy more tools to do a particular job. I would have to see your situation before I could recommend a specific tool, however.

When you say, “Crescent wrench,” do you just mean the classic adjustable wrench or do you mean the Crescent branded flat wrenches and sockets, perhaps made in Taiwan? If you need more leverage on your 13mm combination wrench, try using a second wrench (such as a 14 or 15mm) and lock the open end of the 13mm to the box end of the larger wrench and double your leverage.