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Topic: OX2 replacement, any tips? 1985 5.0 HO (Read 893 times) previous topic - next topic

OX2 replacement, any tips? 1985 5.0 HO

I went to replace my oxygen sensor and there is no way that I can get to it.  Does anybody have any tips?

I may just have to get headers and dual exhaust for an excuse to do away with the stock exhaust manifold.

This is a LTD LX 5.0 HO 1985.  I'm only getting less than 15 mpg, combined hwy and city.

I think this must be impossible to do?  Air pump, AC, other  all in the way.  Can't reach it from the bottom or the top.  To make it worse they angled it towards the firewall and I got a feeling even if I could get to it, it would be rusted tight.

Not one of Fords bettter designs.  But I sure do enjoy driving this car.

TED

OX2 replacement, any tips? 1985 5.0 HO

Reply #1 –
remove the exhaust manifold?
1979 Ford Fairmont
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5.0L/4R70W/8.8"/5-lug/3" Exhuast

OX2 replacement, any tips? 1985 5.0 HO

Reply #2 –
Very temping.

I have a set of Mustang stock headers already but these are also temping from Ford Racing.  Has anybody used these?  Would they be worth the cost over just the stocker?

http://store.summitracing.com/partdetail.asp?autofilter=1&part=FMS%2DM%2D9430%2DP50&N=700+400070+115&autoview=sku

One more question;  When I remove the stock manifolds how many bolts will break off?  Does for have a problem with this?

Also will need a dual exhaust header pipe (no Cats) and crossmember.  Any suggestions here?

Thanks for your help,

TED

OX2 replacement, any tips? 1985 5.0 HO

Reply #3 –
I have those headers on my T-bird. They are nice and work great:D

As for a H-pipe Summit makes a catless one for a Mustang that costs ~$110. I have it and have had no issues with it. Fits great. You will need an extender harness to let the O2 sensors plugs reach but other than that everything should bolt up ok:D
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

OX2 replacement, any tips? 1985 5.0 HO

Reply #4 –
I also have cast iron manifolds, I not sure if all the T-bird/Cougars had this?

Last night I removed the Cat and pulled the line that goes from the cat to the air pump.  Then I removed the lines that went air pump tube in the back of both heads.  Once you do this you can now see spark plug boots and the O2 sensor.

But the trick is that I purchased two different tools and worked on it for an hour and it will not come loose.  Now I found it, it is rusted solid :flip:

So I think the only way to remove it is to take off the manifold, put it in the vise, heat it up good, and get it loose.  This is going to wait for another day because I think I'm going to headers anyway and dual exhaust.

So for now the Cat got the iron bar treatment.  I welded up where the air pump goes to the cat.  I'm leaving the air pump lines off but leaving the tube on the heads with the backfire valve.  I also bent this up so I have more room to get to the plugs.  I had to put a short piece of hose on the backfire valve and block it with a pipe plug to reduce any noise.

Going to leave the old sensor there for now.

The other problem I have is that they put the fuel pump and filter right where the ler would go on the passenger's side.  Don't know if this can be moved since it has the plastic fuel lines.  May have to make a good free flowing single exhaust for now.

So what I'm thinking is the Ford headers list above.  The Summit H-pipe modified for single exhaust (passenger's side plugged), Turbo 2.5 ler and single 2.5 exhaust pipe.  I know it not the best but better than stock.  Then I can just put the no 02 sensor in the new pipe.

But this has to wait for another day.  I guess I will just get bad gas mileage a little longer.

Also found out my MAP sensor was bad;  replace this and the idle is much better now.

TED
 

OX2 replacement, any tips? 1985 5.0 HO

Reply #5 –
Got it all back together.  Found out the pink vacuum line that went to the air pump was broken and this caused a vacuum leak.  Also the line to the air cleaner was off that works the warm air doors in the air cleaner was off.  This would have caused a vacuum leak when it was cold.

So I just disabled both of them.  Air pump has no purpose anymore and there's no reason for warm air in the northwest.

Took it for a test drive and it runs great now.  Perfect idle and a little more power.

Found one more problem with dual exhaust.  The Auto floor shifter is cable operated and the put the bracket right where the drivers side exhaust pipe would go.  I guess I will just leave it stock for now.

TED