First time to post on this website. I have been lurking and reading posts on here for two weeks now in hopes to find a way to solve this problem. I have read Cruiser54's posts, threads, website... etc. I have done several of his tips, but despite my best efforts, I can't solve the issues. So I am finally going to make the desperate attempt to receive some direct tips for the problems I have been facing. (aka i request the help of the renix gods)

The following list is all of the symptoms I have experienced:

• Rough Idle
• Miss Firing
• RPM Limited to 1500 during all states of gear (parked, reverse, drive, etc.) [NEWEST SYMPTOM]
• Back Fires during Idle and when throttling. The frequency increases when increasing RPM.
• It likes to do the boogie. AKA it shakes really bad sometimes.
• Fluctuating Idle RPM.
• Power Loss (?)
• Black smoke occasionally- happens most commonly when it backfire
• Absolutely terrible gas mileage.

The following list is everything I have done in attempt to solve these issues:

• New 12 hole injectors
• New CPS
• New O2 Sensor
• Readjusted TPS [According to Crusier54's tip]
• Replaced TPS
• Replaced literally everything spark plug related (excluding ignition coil and relays)
• New spark plugs (a year ago...)
• New timing chain
• New intake gasket
• New exhaust manifold
• Tested for vacuum leaks, none found.
• Tested CPS, TPS, O2 Sensor
• IAC looks clean and new
• Cleaned throttle body
• Cleaned map sensor
• New battery
• Unrelated but also new brake systems
• New steering components.
• Hit stuff a few times
• New Waterpump
• ... Made a small shrine to it and cried while giving money to it through the exhaust. It denies our sacrifices of bolts.

Here is a list of the tips I have done so far from Cruiser54:

• #1
• #5
• #7
• #8
• #11
• #12
• #13

I will mention as well that is has auto-start and oil pan heater that were installed prior to our ownership of the vehicle. Everything I have listed are off the top of my head mixed with a lot of thinking, so there might be one or two things missing. I am completely clueless with what to do now, and I can't take it to a shop due to it not running correctly, and financial issues as well. I'm also just generally really stubborn about getting this XJ Renix fixed. So I would be absolutely ecstatic if the community can come and help me get this Jeep back on the road. Thank you for reading and thank you all for everything you all have already done through the numerous posts and comments made prior to this.

 

Welcome! Sorry to hear your woes. Sounds like you've covered a lot of repairs. I understand how frustrating it can be. Going back to basics again:

1) What are you currently seeing for vacuum pressure?
2) What is the compression in the cylinders? (did you double-check timing marks?)
3) Check for a couple pesky issues like cracked distributor cap and water in the gas.
4) Temp sensor reading correct?
5) Airflow sensor in the intake clean and reading correct?
6) What do the color of the spark plugs look like? (is it getting the 'right' fuel?)
7) If you unhook the IAC connector, what happens?
8) Throttle body base gaskets good?
9) Fuel pressure and flow?

Those immediately come to mind. Have you put gauges on these things to measure?

[Edit:] I've had a couple times in the past where I filled up with gas, and got a massive amt of water in the fuel. Ran like you describe ...I replaced everything I could think of until I accidentally discovered the water. After running a while look into the throttle body for droplets.

 

Try a little dry gas in the tank. Even if it doesnt help, it wont hurt anything. Could be a dirty tank giving the fuel pump fits, too. Only other thing i can offer is to check the motor mounts, and transmission mount. That could be some of the shaking, but i dont know. What condition was the balancer when you pulled that? If the ring shifted, the timing mark may be off. I dont know if thats part of the issue or not.

I dont know Renix, but i do know that finding a shop that will work on older vehicles isnt as easy as it used to be, so i dont bother. If they cant hook it up to a scan tool that tells them EXACTLY whats wrong with it, i find they want nothing to do with it. Even dealers. IMO, you are better here, than there.

 

When I've had water in the tank, it took about 2-3 tank tankfuls and about 4 bottles of Heet (fuel antifreeze) per tank-full to work itself out. Takes a lot of alcohol to mix in the water ..and even then water doesn't combust very well. It can really screw up a few days! I'd look carefully for any moisture around the throttle body and if you see any, remove the tank and look. Look at the plugs, to see if the insulators are clean as a whistle (steam cleaned). It's easier to remove the tank and look for water than goof around trying to get a lot of water out using fuel alcohol. Ethanol in the fuel in general attracts water. Most gas stations and trucking companies follow good hygiene to prevent it, but it can happen. It's just a thought b/c it's easy to overlook and can cause a lot of head scratching as it mimics other issues and it won't change no matter what sensors or crap ya replace. Chances are slim, but it wasn't on your list of things.

If you don't have a scanner and plan to keep your Jeep, you may consider picking up a Snap-on MT2500 with old cartridges. Should be able to find one fairly cheap that'll work. Gives you real-time readings and info. Let's you know what's going on. The troubleshooter cartridges are good for advice, but you probably got more from this forum. Can use on other legacy cars/trucks too. A Solus Pro is essentially the same thing only more recent, have come down in price, and can work up to 2016. If you look at the Solus revision # it generally works for the vehicles the model yr 'below' the software number (i.e. v13.2 = 2012 and older).

Or there's the Renix monitor from the guy who sells the XJ fan controllers for Renix (Youtube it). I use my old MT2500 and it works great. This one would work:
https://www.ebay.com/itm/Snap-on-MT2...kAAOSw~E5dRcmf