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I need help finding a cps sensor

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You don’t have to pull the tank to remove the sender. It’s just a locking ring there that comes off to remove the sender. 

There are several ways to install a fuel pressure regulator. The goal is to get 50psi to the rail and let all the excess fuel return to the tank. The fuel rail you have now doesn’t have a return line or regulator like the 91-95’s had (renix too). So you’ll need a regulator that has an inlet and two outlets. The feed line from the pump will go to the inlet and the regulated outlet will go to the fuel rail and the other outlet will return fuel to the tank. You’ll have to rig this up and plumb it yourself. I get these sort of regulators from summit racing since it’s a universal part and there are hundreds of versions that would work. Alternatively, you could swap on the older style fuel rail with the regulator built in. You’ll have to swap the regulator for a higher psi one to get you to 50 psi. I’m sure someone who has done their obd2 swap has the regulator information for using the old style rail. 

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  • 3 weeks later...

Ok I’m back! Sorry been gone so long! Work and family have tied me up     In related news if I drive my truck for a hour it dies    After sitting for 30-45 minutes it’s back in business    Would cps sensor do that if it were bad? Also someone asked where one of the gas lines goes ? This one just dead ends  see pic 


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You got a bit of an issue here that I’m sure someone who has done a proper obd2 swap can help with. I can tell you what you need to go aftermarket and fix what you have but it’s quite a bit of mod work involved. The problem you have is that you have what is known as a “return less” fuel system. In 96 when obd2 was introduced Jeep started to phase in a new fuel plumbing system in which the fuel pressure regulator was built into the sending unit as opposed to being on the fuel rail as before. It used to be that there was a feed line from the pump and a return line. The pressure regulator was located on the fuel rail and regulated the pressure by returning all fuel over a set psi to the fuel tank. The newer design uses a regulator in the tank so the supply line from the fuel pump is regulated and doesn’t require a return line since there is never excess fuel pressure. The problem you have is that the old style fuel system was used which requires a pressure regulator and return line. Without that pressure regulator and return line, the fuel pump is just pushing it to the max and only the internal relief valve (if it still works) is giving the pump any relief. Here is your second issue: the newer fuel system electronics you have require a consistent, preset fuel pressure since the fuel mapping is set based on that pressure. I couldn’t say for sure what pressure you are actually getting but my guess is that the internal relief valve of the pump (if it still works) is around 70-100 psi. 

Now here is what you need: it’s going to be a huge ton of work to swap over to the earlier fuel injection electronics at this point. So I would focus on the fuel system. There is no drop-in fuel sending unit with the newer style return-less setup that drops into the MJ tank. XJ parts for the most part don’t fit the tank. Now there may be an oem solution to this that I am unaware of. If there is hopefully someone will chime in.


The aftermarket route would involve installing a stand alone fuel pressure regulator. I use fuelab regulators but there are many options here. I don’t remember exactly the fuel pressure you need to maintain for that obd2 fuel injection system but I believe it is high 50’s psi. Most regulators are adjustable so you will need to set the psi with the engine running to the correct psi. The regulator typically will have a gauge port that you’ll need to tap into or, better yet, get a nice Russell gauge and install it on the regulator. Now the tricky part to explain without me pulling a ton of small connectors and part numbers is the plumbing of an external regulator. You have a single steel line that will have to transition to a rubber line to install the regulator. You will need all the proper adapters and fittings to get this accomplished. I unfortunately don’t have the time to look up all the number you will need. And keep in mind that this is an aftermarket solution so your not going to find a kit that has everything you need. I would suggest using 3/8 and 5/16 hardline quick connect to -6 an fittings. But you’ll also need -6 male o-ring fittings to fuel hose adapters, clamps etc. Napa, oreillys, auto zone center etc won’t have these parts on the shelves and won’t have a clue what your talking about. Summit, Jegs and other will have what you need. 

Also, lookup diagrams for installing an adjustable regulator with return line. That will give you a good overview of how this works I’ll all work. The regulator will probably need to be mounted in your engine bay on the drivers side. 

Once you have the plumbing sorted out, replace that existing fuel pump with just a good quality replacement pump for a 91-92 mj or 91-95 XJ. Again, NOT the sending unit and pump since they won’t fit. You just need the pump since the one you have now has likely had enough. 

Hopefully this will fix your fueling issues for you :L:

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Well...... @#$%. LOL  I was hoping this was gonna be a bit simpler   Thank you very much! At least I have point of reference going from here   Does anyone know of a shop in the south East that would do this kinda thing?

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