There is only one thing I hate about my jeep. The stupid precats. The main cause of my heat soak woes. Is there any way to eliminate them. Only problem I see is the o2 sensors. Who's stupid idea was it to put such a thing right underneath the intake manifold anyway.

Thanks,
Ben

 

You can thank the state of Kalifornia for those. I have them too and hate them. I just wrapped my fuel injectors with the factory kit and so far so good regarding heat soak. If it occurs again I'm going to wrap them with metal insulating tape. I've also considered getting header wrap tape for the exhaust manifold.

 

^ good ideas, I've got the same issues. Might try them out.

 

I have wrapped my injectors still have same problem. I also live in Florida. Temps were in the 90's the other day.

Ben

 

I have this heat shield installed, on top of my manifold, on my 01 and I don't have any heat soak issues. It's hot here in TX. Can be purchased at the dealership.

 

Called dealer. They have one. Going in the morning to snag it up. Hopefully it will work.

Ben

 

How much is the heat shield? Been having some issues my self and we have only had two days in the 80s this year in Maine. Both days it has had the cel come on for miss fire on cylinder 3.

 

I have a 2000, and the heat shield did not fix the Heat Soak issue. "Knock on wood" I haven't had heat soak since my latest attempt at fixing the issue. This is what I did.
Left the heat shield installed.
Any length of fuel line that's under the hood is insulated.
The injector rail is wrapped with header wrap.
Each injector is wrapped with header wrap.
The gaps between the exhaust manifold and the intake manifold at cylinder 1,3,4 and 6 have lengths of header wrap to deflect the heat.
Raised the rear of the hood to let the heat out.
Installed a hood scoop to let more heat out.

My Cherokee had heat soak in the worst way. When working hard on the rocks and getting hot it would shut down. I would have to wait like 30 minutes for it to cool down before it would restart.
Like I said, I think that I've got it fixed now. (knock on wood)

 

I'm kind of a newb still, but I've got a 2000 that gets a little bit of this (maybe a lot, but when I'm done driving it, I'm usually DONE driving it, so it has time to cool down completely between trips). It's not a huge problem for me, but might be worth nipping in the bud I suppose.

BUT, just for my reference, and the general education of others, any wise old XJ owners, mechanics, engineers, or smart guys care to enlighten the class on exactly what's happening with "heat soak," what causes it, how/why wrapping and shielding helps?

Maybe? Please?

 

If this fix doesn't work I think I am going to have to modify the exhaust. I will keep the the O2 sensors before the pre cats. I will simulate the post cat O2 sensors.

Ben

 

I'll take a shot at it. I'm not an engineer or a mechanic. But, because of how close the injectors are (1,3,4,6) to the exhaust manifold, they get very hot. Gas vaporizes in the injectors and they don't work with vapor.

 

Ever since I did the injector swap I havent had too much issue with heat soak, I do have my rail wrapped tho. My jeep had the heat sheild done right after it was bought .
My wife bought the jeep brand new .

 

Well the shield is installed. Now we wait and see.

Ben

 

Update?

 

So far so good.

Ben