cruiser54

What pressure?

It fools the ECU into firing earlier. Just fools it as to initial timing. Wanna read about it? CRUISER'S MOSTLY RENIX TIPS RENIX CPS ADVANCE MOD NOVEMBER 17, 2015 SALAD 25 COMMENTS EDIT The sensor portion of the CPS needs to slide up the perforated bar towards the top of the engine. Mark the perforated bar’s top end with paint or marker. Place the CPS in a vice, just not quite clamping the bar, the sensor resting on the vice jaws, with the Top part protruding. Place a bolt that fits tightly into the hole at the Top part of the bar. With a hammer, tap the Top part of the bar and it will slide through the sensor portion of the CPS. Stop when the sensor portion is about 3/8″ from the edge of the bolt hole.

You have a manual trans? That would explain the empty connector on the TPS near the throttle body. Why not cut the 10 pin connector out and solder the wires together? It serves no purpose except to help build the Jeep on the assembly line.

That's my point. You don't give 2 $#!&s if you waste people's time and money by dropping half-assed answers in threads and then go on "enjoying life" afterwards. What about THEM?

Who knows?

Well, once the intake manifold goes away, you'll need to go back to Renix power steering brackets, pump etc. Should be easy to find. I think I have a Renix bored TB.

Won't have spark if CPS is bad!! You are GUESSING it's the CPS even when there is evidence that it's not. And how can something that generates a signal like a CPS retard the timing? Do you not feel any accountability/responsibility to those asking for advice? Is their time and money not important to you? These people are relying on us for good advice, not guesses. Hell, THEY can guess just as well as we can.

Fuel pressure has not been verified with a gauge!! Let's quit guessing. If fuel pressure was good, it woulda sprayed the piss outta the OP. The Tips are always a must to do and are free. CPS is generally no start and no spark. As for the ballast resistor, it is NOT to save your fuel pump. It allows the fuel pump to get 12 volts when cranking, but about 9 volts when running. That keeps the pump QUIET and was the only reason the factory equipped the Jeeps that way and came out with a retro-fit to address customer complaints. The crank sensor does NOT retard the timing. It READS the flywheel slots only and sends an AC voltage signal to the ECU. All that crap straightened out I hope. Try starting fluid and see what happens. Down and dirty way to see if it's a fuel issue.

Put a Renix intake manifold, throttle body etc on it and use that system. That "injector" connector goes to the knock sensor down near the oil pan driver's side block. The other plugs go to oxygen sensor and CTS.

The grounds at the dipstick tube stud....is the connection on the block clean and shiny, or covered in thick paint? This^^ in addition to what jdog suggests.

CRUISER'S MOSTLY RENIX TIPS CONNECTOR AND RELAY/RECEPTACLE REFRESHING OCTOBER 30, 2015 SALAD 29 COMMENTS I suggest unplugging EVERY electrical connection in the engine bay you can find, whether engine related or not, and spraying it out with a good electronics cleaner, visually inspecting the terminals making sure they haven’t retracted into the plastic holder, and then plugging it back together. There’s a critical 10-pin connector for the front lighting system located in front of the air cleaner and behind the left headlight assembly. Don’t miss that one. Also be sure that the connectors to the ballast resistor mounted near the air cleaner housing are clean and tight. ALL of the relays should be removed, the terminals wire-brushed until shiny, and the receptacles sprayed out with contact cleaner. Then plug them back in. I do this on every Renix Jeep I purchase or work on for someone else.

CRUISER'S MOSTLY RENIX TIPS RENIX GROUND REFRESHING OCTOBER 30, 2015 SALAD 62 COMMENTS The Renix era XJs and MJs were built with an under-engineered grounding system for the engine/transmission electronics. One problem in particular involves the multiple ground connection at the engine dipstick tube stud. A poor ground here can cause a multitude of driveabililty issues, wasted time, failed emission tests, and wasted money replacing components unnecessarily. All the components listed below ground at the dipstick tube stud: Distributor Sync Sensor, TCU main ground, TCU “Shift Point Logic”, Ignition Control Module, Fuel Injectors, ECU main ground (which other engine sensors ground through, including the Oxygen sensor, Knock Sensor, Cruise Control and Transmission Sync signal. All extremely important stuff. The factory was aware of the issues with this ground point and addressed it by suggesting the following: Remove the nut holding the wire terminals to the stud. Verify that the stud is indeed tightened securely into the block. If the whole stud turns, you can use a 7/32″ six point socket or wrench to hold it so the nut can be removed. Worst case, cut the wires and remove the stud and nut. Install new terminal eyelets on the wires when going back together. Scrape any and all paint from the stud’s mounting surface where the wires will attach. Surfaces must be clean, shiny and free of any oil, grease, or paint. Inspect the wire terminals. Check to see that none of the terminals are crimped over wire insulation instead of bare wire. Be sure the crimps are tight. It wouldn’t hurt to re-crimp them just as a matter of course. Sand and polish the wire terminals until clean and shiny on both sides. Apply a liberal coating of OxGard, which is available at Lowe’s and other stores. Reinstall all the wires to the stud and tighten the nut down securely. While you’re in that general area, locate the battery negative cable which is fastened to the engine block just forward of the dipstick stud. Remove the bolt, scrape the block to bare metal, clean and polish the cable terminal, apply OxGard, and reattach securely. Another area where the grounding system on Renix era Jeeps was lacking is the engine to chassis ground. There is a braided cable from the back of the cylinder head that also attaches to the driver’s side of the firewall. This cable is undersized for its intended use and subject to corrosion and poor connections at each end. Remove the cable end from the firewall using a 15mm wrench or socket. Scrape the paint off down to bare metal and clean the wire terminal. Apply OxGard. Reattach securely. Remove the other end of the cable from the rear of the head using a 3’4″ socket. Clean all the oil, paint and crud from the stud. Clean the wire terminal of the cable and reattach securely with a liberal coating of OxGard. 2 STRONG suggestions regarding the ground system: I prefer to add a #4 gauge cable from the firewall to a bolt on the rear of the intake manifold, either to a heat shield bolt or fuel rail bolt. A cable about 18″ long with a 3/8″ lug on each end works great and you can get one at any parts store already made up. NAPA has them as part number 781116. A further improvement to the grounding system can be made using a #4 cable, about 10″ long with 3/8″ terminals at each end. Attach one end of this cable to the negative battery bolt and the other end under the closest 10mm headed bolt on the radiator support just forward of the battery. NAPA part number 781115. For those of us with Comanches, it’s very important to remove the driver’s side tail lamp assembly to access the ground for the fuel pump. Remove the screw holding the black ground wire. Scrape the paint from the body and corrosion from the wire terminal. Add a 10 gauge wire, with an eyelet on each end, from that grounding point to a bolt on the frame. Better yet, on both Cherokees and Comanches, complete Tip 29 for the best fuel pump grounding. Be sure to scrape all mounting points to bare metal and apply OxGard also. If you want to UPGRADE YOUR GROUND AND BATTERY CABLES with custom made parts, contact Paul at www.jeepcables.com Revised 02/04/2017

Have you cleaned the cable at the firewall?

Make sure you don't use the Chrysler fluid in your AW4 auto trans!! Regular old Dex/Merc ATF. And, you only need to do a drain and fill using the pan plug. Takes about 3.8 quarts.

I ran the blower and misted a mild bleach solution through the cowl grille.

Just do them. Can't hurt and likely helps.

Yank the air cleaner assembly to gain easier access to the lower bolts.

Yep. And the torque spec is different....

The ground strap firewall to head is super important on the 4 cylinders. Complete Tip 1 first.

Neither sender/sensor will cure an overheating issue. That radiator looks skanky. Perfect time to convert to an open cooling system. Get a NR2802 radiator from NAPA. It will have the cap on it.

What year? What engine? Does your truck have dash gauges or idiot lights? If it's 90 or earlier, have you completed Tips 1 through 5 from my website?

Yes.

Spray with carb cleaner along intake and those hoses.

For some reason, that ground strap is much more critical on the 4 cylinder. Yeah, do the Tips. Did you inspect the intake bolts and those hoses though?