1989 exhaust manifold question.

[Cory88]

Hi everyone, new to the site. I have a question for the experienced xj owners. I have a cracked exhaust manifold and i was looking at buying a new one rather than welding the old one to patch it up. the only thing is the aftermarket brands dont offer much for pre 91 engines. Being an 89 with EGR only a few places have them and look OEM, i was looking a more at a perf header. has anyone ever removed the egr and do they recommend doing it or what? any advice would be great.

Thanks

 

[js_customs]

Here's the header I have on my 88

http://www.cliffordperformance.net/...de=CP&Product_Code=57-2015&Category_Code=J258

and I got the y pipe for it to run single exhaust

http://www.cliffordperformance.net/..._Code=CP&Product_Code=11-J&Category_Code=J258

If you can get away with deleting the EGR system, then you could make up a plate to block it off. It wouldn't pass emissions then, I'm not sure how that works in Canada...

 

[Cory88]

sweet, ill look into that.

Did it make your mpg change and have any effct on the way the engine runs/warms up or stalls sputters with the egr blocked off? Or did you reconnect it?

I'm being searching all jeep sites that i know of, lol no straight direct anwsers yet but this is a start.

Thanks

 

[cruiser54]

They run perfectly fine wothout EGR as far as performance. No ill effects.

 

[Cory88]

only effct would be emissions then.

 

[jeepintexas]

you need 2 drainplugs off a cummins diesel. and a plate to block off the entry. no adverse effects to report.

 

[Boatwrench]

I ordered an aftermarket exhaust manifold from APN, it was not that expensive, it came rather quickly and it is legal.

Don't forget to check and change your motor mounts and the transmission mount, a leading cause of manifold cracking.

 

[JeepFreak21]

Let's not give the greenies any extra ammo, k?

Deleting the EGR is ILLEGAL and does NOT condone it!

Billy

 

[js_customs]

Yeah I reconnected the EGR. There is a bung for it, but I'd recommend making up a new egr tube...I've cracked a bunch since the stock one isn't long enough.

 

[joe_peters]

I would buy the APN header and have a muffler shop mount an EGR bung on it. The APN is about the best engineered header I have seen for the 4.0; that said, I would still put a short stainless steel flex piece in between the CAT and the downpipe, this eliminates the header cracking torque. Also, make sure your engine and trans mounts are good.

 

[MJR]

There are several aftermarket replacements I thought for Rennix like Pacesetter and Borla if they still make them.

The EGR is the reason the Rennix gets better fuel economy than the HO.

 

[joe_peters]

There are several aftermarket replacements I thought for Rennix like Pacesetter and Borla if they still make them.

The EGR is the reason the Rennix gets better fuel economy than the HO.

I always thought it was our superior driving skills, coupled with the 13 less HP, that gave us better mileage.

 

[Johnnie Walker]

I've not seen any mileage gain/drop in my Renix with EGR work/not

 

[MJR]

I always thought it was our superior driving skills, coupled with the 13 less HP, that gave us better mileage.

I've got as high as 18mpg on the way to Moab before driving behind a motorhome. And I have 35" tires and 4.88 gears!

The Rennix also has the knock sensor that the HO doesn't. Both items allow the Rennix to run less fuel/leaner than an HO.

 

[Slip Kid]

I've not seen any mileage gain/drop in my Renix with EGR work/not

Its probably more like "the things they did to the HO to get it to meet emissions standards without an egr is the reason why the HO gets worse mileage"

I agree that its presence/absence makes no difference in economy.

It takes exhaust, and puts it into the intake.... think about it....

 

[MJR]

I agree that its presence/absence makes no difference in economy.

It takes exhaust, and puts it into the intake.... think about it....

And if you put exhaust in the intake what does that do?????

When you put exhaust gas (which cannot be burned) in it displaces air that can be mixed with fuel and burned. So to not make the mixture rich the engine controller reduces the fuel injected. That reduces fuel usage.