There's no EGR Valve on a 1991 Supercharged SC 3.8

BlackSunShine

Registered User
If you own a 1991 Supercharged 3.8, your car does not have an EGR valve. Take a look under the hood at the vacuum diagram. It won’t show an EGR or vacuum line. I just spend the past day, attempting to determine if mine had one. If you look for that part online, you will find it. My parts store even ran the VIN and sold me the part. Most auto parts stores list an EGR for the SC.

This may not be true for other year SC’s and the Ford 3.8 non SC does have such a part. I’m in California, and dealing with Smog issues on my ride that has 41,000 original miles. Car is rarely driven… CA should exempt low mileage vehicle from their silly inspections! …Now, on to find the culprit for the High NO reading. Hope this saves someone else some research time.
 
Auto SC's dont have EGR, but the Manuals do
Ya... I found this on here after my post. May be helpful to someone in the future:


The ’89 and ’90 5-speed and AOD cars as well as all the ’94 and ’95 cars had
EGR. There may be a few exceptions to this rule, but this information is
generally accepted as true.

SC EGR by Year/Transmission Type

89 - Both: Had EGR

90 - Manual: Had EGR
90 - Auto: No EGR

91 - Both: No EGR

92 - Both: No EGR

93 - Both: No EGR

94 - Both: Had EGR

95 - Both: Had EGR
 
I'm wondering whether having an EGR or not would matter to headgasket life, because although they're hot exhaust gases going back into the system, the EGR allows for more timing at cruising speeds and aids in cylinder filling when the load is low and vacuum is higher.
 
I had High NOx readings and I had to change cats....maybe someone on hear knows a trick. this was a 92 auto with no egr. I'm looking at magna flow 50 state cats for my 5 spd now. they're about $125 each online. as for the headgasket thing I think all early 90s 3.8 were prone to head gasket failure. I remember our old shop always had a fwd 3.8 Taurus or Lincoln in there with blown gaskets after about 90K miles I'm sure boost doesn't help. I don't remember 5.0 or 2.3 having as many problems but that's just what I remember from many many yrs ago. I think it might be materials and vehicle maintenance.
 
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