A little help please? EGR/Oil Pressure Sender

Hello,
I have an 88 TC, and I am having major problems getting my car to run at all right now. It will barely stay running and lounds like it is massively detonating all the time. I have two questions.
1. After reading the EGR section of the FAQ, it sounds like the EGR diaphragm should move during a KOER code test. Is this correct? I think mine is frozen up.
2. Also noticed my oil pressure sender is leaking like a sieve, and I am trying to replace it, but even with the EGR off, I can't get enough access to turn a wrench to remove the sender. Does anyone have any tricks for this?

Any help is greatly appreciated.
Thanks.
Best Regards,
Jim

have you tried moving the egr valve diaphragm by hand? also it might be easier to go up from the bottom to get to the oil sending unit. hope this helps.

I'll give the bottom approach to the sender removal a try. Regarding the egr, I have tried to move it by hand but it only moves about 1/16" right now I have it off and cleaned it with carb cleaner and I am trying a soak with some penetrating oil at the seat, but it still seems frozen.

The EGR valve should be closed by default unless carbon build up is holding it open. They do need to be cleaned occasionally. The EGR is not normally open at idle

I've had a very similar detonation problem before. I agree it sounds like you have an air or vacuum leak but it may not be the EGR. Have you examined the VAM hose and the 2 inter cooler hoses for holes, cracks or not being properly seated and clamped. VAM hoses will get holes in them and can be hard to seat and clamp on the back of the VAM. Take it off and examine thoroughly. On the IC hoses, take them off and very thoroughly look them over, 360* and squeeze them to open up any crack. I chased an air leak for longer than I want to admit because I didn't start with hose exam. Mine turned out to be a growing hole in the lower IC hose, covered by a hose clamp.

For the oil sender leaking:
What I use is a crow's foot wrench, A long 3/8th extension, notched
to clear the bottom bead on the OP sensor. I don't recommend putting channel locks on the outside of the sender, at least until it is broken loose.

See these photos, it's pretty self explanatory. Also don't use teflon tape on the threads of the new sender, use teflon goop.
Don't use teflon tape on any threads in relation to the lubrication system, that includes fittings for the turbo. Use the goop. Notice the notch in the 3/8" extension.
http://s294.photobucket.com/user/turbopm...t=3&page=1

Holy Cow Pete! Those pictures are definitely worth a thousand words! Thank you very much. Now all I need to do is find one. Do you know where I can buy one?

Regarding the EGR, it definitely feels stuck. I'll probably need to buy a new one.

Regarding the vacuum leak, that was my first thought too. I removed the VAM hose completely and inspected it, and I removed the IC to inspect those hoses, but I did not remove them completely. I'll do that tomorrow, and hopefully I'll find a split in one.

Thanks.

Crows foot wrenches often come in packs, each wrench a different size from the others, either SAE or metric.
I know Sears has them but someplace else might be cheaper

You could test the EGR by attaching one of those hand pump vacuum tools to the diaphragm and create vacuum to see if it moves.

You can even hook a hose to the EGR valve and suck on it to see if the diaphragm moves. It doesnt take much vacuum to get it to move.

The egr barely moves at all. I just ordered a new one because this one won't free up and start moving. I also ordered a set of crow's foot wrenches. Hopefully it won't take too long to get them.

Well, I got the EGR and the Crow's foot wrenches. I had to order both of them. I was able to swap the oil pressure sender with the new wrenches (Thanks for the info Pete!). And the EGR was definitely bad. However, as Pete correctly suggested, the EGR had no effect.

It is still detonating badly and won't run without feathering the gas pedal. I went through the intake system and disassembled and inspected everything, and I can't find any vacuum leaks.

Does anyone have any other suggestions?

Thanks.

Check the fuel system using http://turbotbird.com/techinfo/Fuel_Syst...ostics.htm

Did you check all the fastener torques for the TB, upper intake and the lower intake to head. I have seen the out of sight bolts on the bottom of the lower intake be loose or even missing.