It will need the MAP. See what the others think..the "Exhaust Gas Reticulation" valve, there in the middle of the manifold is a built in vacuum leak. It should only get vacuum to it's diaphragm when the ECU activates it's solonoid there on the drivers inner fender. For diagnosing, you can pull and plug the line on the EGR valve. (make sure you don't leave a ball bearing in that line). Then it would never work.

I'd have been asken about your 02 sensor if your vacuum was not so low. With 703's in mine I run rich ALLOT, cuz on "defalut pulse with", that is what you get with 703's in a Renix. When it is up to temp with the 02 sensor "trimming" the mix it's supper! Nearly 25 on the freeway! 14MPG otherwise.

I'm checking that highway mileage again tomorrow...

 

Dflintstone nailed it on the head. The egr valve solenoid is bad and was always pulling a vacuum on the egr valve, causing a huge vacuum leak. Next question is I've just plugged the vacuum port going into the egr solenoid, do I need to replace this or will I be ok just bypassing the egr system?

With the vacuum port plugged on the egr solenoid I'm getting a steady 17in hg of vacuum and she idles better than she ever has. Map sensor is also working like it should ill have to see if my gas mileage also improves.

 

Bump to know if the egr system can be bypassed without any issues. I don't any sort of emissions testing so that is not an issue.
Thanks

 

Discussion on this forum of disabling emission system components is strictly forbidden. Check your PMs.

 

I gather it would violate forum rules and even federal law to talk about disabling such a thing. And hey, it was designed to work with the thing, and we all DO breath (I meant "breathe"), air. So there's that. Glad you found the problem!

 

Dang. I typed all that in less then 15 minutes and you still beat me to the punch! (some sort of moderator "black magic" no doubt).

 

Ooga Booga.

 

Thanks for the help everyone, the xj is running the best it has since I have owned it. Refreshing all the wiring and fixing the vacuum leak made a night and day difference.

 

I love happy endings and simple solutions.

 

Cruiser, you're a flippin' stud. I was having an almost identical issue as the OP. Just about every thread I could find for Renix with a worthwhile reply was from you (or Blue, of course). Thanks for being so free with your Renix advice, my friend!

 

Enjoy your Jeep, and thanks for the kind words.